Edited by Tanja Wolf and Bettina Menne
Environment and health risks from
climate change and variability in Italy
ii
ABSTRACT
The World Health Organization (WHO) and the Italian Agency for Environmental Protection and Technical Services (Agenzia per la Protezione dell' Ambiente er per i servizi Technici, APAT) are collaborating in a project on climate change and health. This report is one of the results of that project.
Climate change is already having an effect in Italy, as elsewhere. The global effects of an increasing concentration of greenhouse gases in the atmosphere are reflected in the growing number of extreme weather events, such as heat-waves and intense rainfall. These have various consequences for the health of a population, both directly in terms of mortality and morbidity, and indirectly through changes in the ecosystem.
As there has been, as yet, no systematic national climate change impact assessment in Italy, this report is a preliminary evaluation of the situation, using international and national literature and with the help of expert advice. The aim is to assess the potential risks of climate change to human health in Italy, to see what adaptive and preventive measures are available and to suggest what may be additionally needed.
Keywords CLIMATE
ENVIRONMENTAL HEALTH RISK FACTORS
GREENHOUSE EFFECT RISK MANAGEMENT
ITALY
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Foreword I
Climate change and climate variability are and will be a threat to human health, as has been highlighted by the recently
published fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC). Climate change already
affects human health directly, for example through increased heat stress or loss of life in floods and storms, and
indirectly through changes in water availability, air pollution and the ranges of disease vectors (for example mosquitoes),
waterborne pathogens and foodborne diseases.
In Italy, the heat-waves in 2003 and 2006, the changes in rainfall patterns and temperature and the already visible
effects on fauna and flora have given a strong signal of the public health challenges that need to be addressed now and
in the near future. The Mediterranean countries, Italy among them, are one of the regions of the world most vulnerable
to climate change. Because of the global and national delay in putting into practice any effective mitigation strategies,
more effort will have to be put into adaptation measures to limit the societal consequences of the changes in climate
which are already occurring.
I believe this first report on climate change in Italy shows the need both for further research and prompt action. The
report shows that information to assist in anticipating potential threats and impacts can be developed and can be
extremely useful in preparing people and the overall societal structure for adverse events, as well as in facilitating the
response as extreme weather-related events occur. This is a new dimension for public health which reverses traditional
thinking: from describing what has already occurred to taking action on the basis of prediction, surveillance, monitoring
and early warning to prevent negative health consequences in large populations. This requires the development of
policies which effectively address expected events, empowering people with information and education, strengthening
partnerships between different economic and social sectors, as well as ensuring that existing services are maintained
and upgraded as necessary to allow for an effective response. Adaptation strategies will need to address health issues
through a comprehensive approach alongside other interventions: this synergy, together with more effective results, will
guarantee a more economically sustainable approach.
The preparation of this report has generated a number of conclusions and recommendations for Italy and the whole
international community. The challenge is now to translate this knowledge into policy, action and, where necessary, into
further research to improve modelling, extend time frames of predictions and enhance the effectiveness of adaptation
and mitigation strategies. Undertaking actions to decrease the extent, speed and intensity of climate change, coupled
with adaptation policies and measures, will help to limit the impact of climate change and to protect the health of both
present and future generations. We hope this report can contribute towards moving the agenda forward without further
unjustified delay. The time to act is now!
Roberto Bertollini, Director
Special Programme on Health and Environment, WHO Regional Office for Europe
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Foreword II
The World Health Organization (WHO) estimates that about 20% of mortality in Europe is attributable to
environmental causes. This is based on the available evidence and highlights the importance of improving
action to combat environmental risks. For this reason the environment and the health sector are among the
priorities of the Agency for Environmental Protection and Technical Services (APAT) programme.
On the other hand, the monitoring of the environment is one of APAT’s most difficult tasks. To improve
environmental monitoring, a network of competent and experienced partners is essential. The need for such
a network is even more prominent in the case of monitoring that aims to identify environmental health
determinants. The selection of these determinants necessarily has to be the result of consultation with
experts from both the environmental and the health sectors.
This led APAT to collaboration with organizations in the health sector, primarily with WHO and the Istituto
Superiore di Sanità, with the aim of directing initiatives and assessing exposure levels of the population to
different health risk factors. Among the initiatives which have resulted in important reports are those on the
health effects of environmental air pollution in Italian cities, realized in collaboration with WHO in 1999 and
2005.
The aim of APAT is, however, not only to increase knowledge on already known risk factors for people’s
health, but also to study and analyse emerging risk factors, for example noise, electromagnetic fields,
contaminated sites and those related to environmental scenarios, so that environmental protection measures
can be strengthened. As part of this perspective, APAT started the project on climate change and health in
collaboration with WHO. For many years WHO has been investing resources into this field and has
contributed substantially to the IPCC fourth Assessment report. Climate change is in fact an emerging
environmental risk factor and a priority on the political agenda of the majority of countries. Italy too is facing
the challenges on both, technical and institutional levels to measure, plan and act efficiently in order to
prevent adverse health impacts in the medium and long term and to integrate this into national sustainable
development policies.
The broadening of knowledge concerning the potential environmental consequences of changes in weather
and climate on health, well-being and survival is a fundamental step for APAT, particularly at this moment
when APAT and other environment agencies are fully involved in developing a national strategy on
adaptation to climate change. Agreement on a national adaptation planwill be the aim of this National
Conference on Climate Change.
At this meeting the report will represent a significant contribution towards an initial analysis of the national
socioeconomic impacts and potential adaptation options. The contributions in this report result from expert
evaluation of the available data and the most relevant results of international and national research into
health and the environment. The results of this first national analysis already allow proactive reflection about
the strengths and weaknesses of the present information system and knowledge on emerging risks.
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The study of future scenarios requires our full commitment, in particular for enhancing strategic
collaboration among the different institutions involved. Communication of our existing knowledge about the
prevention of harms and our responses to climate change are essential to enable the informed participation
of all citizens.
Giancarlo Viglione, President
APAT
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Acknowledgements
This publication is the result of a collaborative project between the Agency for Environmental Protection and
Technical Services (APAT) of Italy and the WHO European Centre for Environment and Health. The editors
would like to thank Luciana Sinisi (APAT), Michele Faberi and Roberto Bertollini (WHO Regional Office for
Europe) for this initiative and their collaborative spirit.
This publication would not have been possible without the contributions and knowledge provided by Marco
Bindi, Centro interdipartimentale di Bioclimatologia Università di Firenze; Monica Francesca Blasi, Istituto
Superiore di Sanità; Mario Carere, Istituto Superiore di Sanità; Lorenzo Cecchi, Centro interdipartimentale di
Bioclimatologia Università di Firenze; Luciana Croci, Istituto Superiore di Sanità; Valentina Della Bella,
Istituto Superiore di Sanità; Franco Desiato, APAT; Francesca de Donato, Dipartimento di Epidemiologia ASL
Roma E; Francesco Forestiere, Dipartimento di Epidemiologia ASL Roma E; Enzo Funari, Istituto Superiore di
Sanità; Domenico Gaudioso, APAT; Ursula Kirchmayer, Dipartimento di Epidemiologia ASL Roma E; Anna
Luise, APAT; Giancarlo Majori, Istituto Superiore di Sanità; Laura Mancini, Istituto Superiore di Sanità;
Stefania Marcheggiani, Istituto Superiore di Sanità; Angiolo Martinelli, ARPA Umbria; Francesco Mattera,
Istituto Superiore di Sanità; Paola Michelozzi, Dipartimento di Epidemiologia ASL RM/E; Marina Miraglia,
Istituto Superiore di Sanità; Marco Morabito, Centro interdipartimentale di Bioclimatologia Università di
Firenze; Marco Morindo, Centro interdipartimentale di Bioclimatologia Università di Firenze; Antonio Navarra,
INGV; Simone Orlandini, Centro interdipartimentale di Bioclimatologia Università di Firenze; Mara Stefanelli,
Istituto Superiore di Sanità; and Andrea Toreti, APAT.
The editors further thank the following experts for participating in the first and second expert consultations
on assessing health impacts of climate change in Italy, in Rome, Italy, on 23 November 2005 and 19 October
2006: Dr Carlo Peducci, Dipartimento di Epidemiologia, ASL Roma E; Dr Luciana Sinisi, APAT; Dr Francesca
de Maio, APAT; Dr Valentina Minardi, Istituto Superiore della Sanità; Giorgio Bartolini, Centro
Interdipartimentale di Bioclimatologia Università di Firenze; Bernardo Gozzini, CNR-IBIMET, Instituto di
Biometereologia; and Roberto Vallorani, CNR-IBIMET, Instituto di Biometereologia.
This publication has been submitted to several stages of expert review and the authors would also like to
thank those who have provided additional comments but who are not listed here. For the editing of the
English text we thank Charlotte Huntly. Thanks to Colin Soskolne and Sari Kovats for reviewing and
commenting on an earlier draft.
We hope that this publication will help to increase discussion in Italy and will support further initiatives in this
field.
Tanja Wolf and Bettina Menne
WHO Regional Office for Europe
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Contents
Foreword I.................................................................................................................................................. i
Foreword II ................................................................................................................................................ii
Acknowledgements..................................................................................................................................... iv
1. Introduction........................................................................................................................................ 1
1.1 Current knowledge on climate change and health................................................................................... 2
1.2 The attribution of health effects to climate change ................................................................................. 3
1.3 The framework used in this assessment ................................................................................................ 4
1.4 Content of this publication.................................................................................................................... 5
2. Climate change and variability in Italy ................................................................................................... 6
2.1 Italy’s contribution to climate change .................................................................................................... 6
2.2 Observed climate change in Italy .......................................................................................................... 8
2.3 Scenarios of climate change for Europe ................................................................................................14
3. Observed and projected impacts of climate change and variability in Italy ...............................................20
3.1 Water................................................................................................................................................21
3.2 Ecosystems, forests and agriculture .....................................................................................................27
3.3 Urban environments and socioeconomic sectors ....................................................................................31
4. Observed and projected health impacts of climate change and variability in Italy .....................................36
4.1 Heat and health .................................................................................................................................37
4.2 Cold and health ..................................................................................................................................43
4.3 Flooding and health ............................................................................................................................44
4.4 Air quality and health..........................................................................................................................46
4.5 Vector-borne diseases.........................................................................................................................49
4.6 Food and health .................................................................................................................................54
4.7 Water and health................................................................................................................................56
5. Strategies to reduce the environmental and health impacts of climate change and variability ....................63
5.1 Introduction.......................................................................................................................................63
5.2 Reduction of greenhouse gases: mitigation ...........................................................................................64
5.3 Adaptation to climate change ..............................................................................................................71
5.4 Public health adaptation actions to address climate change ....................................................................72
6. Conclusions.......................................................................................................................................85
6.1 Observed changes and scenarios .........................................................................................................85
6.2 Health risks........................................................................................................................................86
6.3 Public health action ............................................................................................................................88
6.4 Information initiative ..........................................................................................................................89
6.5 Health services assurance ...................................................................................................................89
References................................................................................................................................................90
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1. Introduction
– by Tanja Wolf, Bettina Menne
Increasingly intense economic activities are triggering a range of global environmental risks to health and well-being of unprecedented scale and of a systemic nature. Climate change is a burgeoning reality. The global mean surface temperature has increased by 0.74±0.18°C over the last 100 years, while the global average sea level has risen by 1.8 mm per year since 1961, and Arctic sea ice is shrinking by 2.7±0.6% per decade. In addition, the sea surface temperature is rising, mountain glaciers are retreating at increasing rates, surface ocean waters are getting more acidic and more frequent extreme weather events have been observed. Human beings are exposed to climate change through changing weather patterns (for example more intense and frequent extreme events) and indirectly through changes in water, air, food quality and quantity, ecosystem functions, agriculture and the economy. Today, it is certain that climate change contributes to the global burden of disease and premature deaths. Emerging evidence of the effects of climate change on human health show that climate change has not only altered the distribution of some infectious disease vectors and the seasonal distribution of some allergenic pollen species, but has also increased the risk of heat-wave-related deaths. In the future, exposure to the effects of climate change is likely to lead to various trends related to human health, such as an increase in undernutrition globally and in the number of people suffering from diseases and injuries directly related to heat-waves, floods, storms, fires and drought. The incidence of diarrhoeal diseases and the frequency of cardiorespiratory diseases as a result of higher concentrations of ground level ozone are also likely to increase. Climate change is expected to have mixed effects on infectious diseases, and might bring some benefits to health, through, for example, fewer deaths from exposure to the cold. However, this is expected to be outweighed by the negative effects of rising temperatures worldwide, in particular in developing countries (Confalonieri et al., 2007). The dilemma with climate change is that it is different from many of the other types of environmental exposures: all countries in the world are affected; it is expected to become more acute over the next decades, even with greenhouse gas emissions stabilizing at year 2000 levels – and thus children will be those most affected; it plays an important role in the spatial and temporal distribution of infectious diseases and thus can affect health security; the effects are unequally distributed and are particularly severe in countries with already high disease burdens or in populations with low adaptive capacity; and the effects are highly complex and will involve a number of processes, developments, sectors and activities. Furthermore, recent events have demonstrated that populations and health systems may be unable to cope with increases in the frequency and intensity of extreme weather events. These events can reduce the resilience of communities, affect vulnerable regions and localities and overwhelm the coping capacities of most societies. This is a preliminary evaluation report, using international and national literature and with the help of expert advice. The aim was to assess the potential risks of climate change to human health in Italy, to see what preventive actions are available and to suggest what may be additionally needed.
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1.1 Current knowledge on climate change and health
Human societies have had long experience of naturally occurring climatic vicissitudes. The ancient Egyptians, Mesopotamians, Mayans and European populations were all affected by nature's great climatic cycles. More importantly, disasters and outbreaks of disease have occurred often in response to the extremes of regional climatic cycles. Hippocrates already recognized that people cannot understand diseases without looking at the wind, the sun and humidity.
Weather is the continuously changing condition of the atmosphere, usually considered on a time scale that extends from minutes to weeks. Climate is the average state of the lower atmosphere, and the associated characteristics of the underlying land or water, in a particular region, usually spanning at least several years. Climate variability is the variation around the average climate, including seasonal variations and large-scale regional cycles in atmospheric and ocean circulations such as the El Niño – Southern Oscillation (ENSO) or the North Atlantic Oscillation. Climate change occurs over decades or longer time scales. Until now, changes in the global climate have occurred naturally, across centuries or millennia, due to continental drift, various astronomical cycles, variations in solar energy output and volcanic activity. Over the past few decades it has become increasingly apparent that human actions are changing the composition of the atmosphere, thereby causing global climate change. The First World Climate Conference, in 1979, recognized climate change as an increasing problem. The World Meteorological Organization (WMO) initiated the World Climate Programme that same year. In 1988 the United Nations Environment Programme (UNEP) and WMO established the Intergovernmental Panel on Climate Change (IPCC). The IPCC was asked to assess the state of existing knowledge about the climate system and climate change; the environmental, economic, and social impacts of climate change; and the possible response strategies. Its first assessment report was released in 1990; the latest (the fourth assessment report) was released in 2007. In 1992, the United Nations Framework Convention on Climate Change (UNFCCC) was initiated at the United Nations Conference on Environment and Development. The UNFCCC aims to stabilize greenhouse gas concentration in the atmosphere, within a time frame sufficient to allow ecosystems to adapt to climate change. It thus accepts that some change is inevitable. Impacts will be felt on ecosystems – and on human health – affecting agricultural production and food security, sea levels, biological diversity, water resources, infrastructure, industry and human settlements. The Kyoto Protocol to the UNFCCC has brought focus and strengthened the international response to climate change. Recognition of the emerging problem of global climate change has hugely stimulated research into the working of the world’s climate. Increasingly sophisticated models have been developed of entrapment of energy by gases in the lower atmosphere, of changing energy flows in the atmosphere and oceans, and of the resulting changes in temperature and precipitation around the world. Studying the impact of weather events and climate variability on human health requires appropriate specification of the meteorological “exposure”. Weather and climate can each be summarized using various spatial and temporal scales. The appropriate scale of analysis, and the choice of any lag period between exposure and effect, will depend on the anticipated nature of the relationship. Much of the research requires long-term data sets with information about weather/climate and health outcome on the same spatial and temporal scales. In all such research, there is a need to accommodate the several types of uncertainty that are inherent in these studies. Predictions about how complex systems such as regional climate systems and climate-dependent ecosystems will respond when pushed beyond critical limits are necessarily
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uncertain. Likewise, there are uncertainties about the future characteristics, behaviours and coping capacity of human populations. In the early 1990s there was little awareness of the health risks posed by global climate change. This reflected a general lack of understanding of how the disruption of biophysical and ecological systems might affect the longer-term health and well-being of populations. There was little awareness among natural scientists that changes in their particular objects of study – climatic conditions, biodiversity stocks, ecosystem productivity and so on – were of potential importance to human health. Indeed, this was well reflected in the meagre reference to health risks in the first major report of the IPCC, published in 1991. Subsequently, the situation has changed. The IPCC second assessment report (1996) devoted a full chapter to the potential risks to health. The third assessment report (2001) did likewise, this time including discussion of some early evidence of actual health impacts, along with an assessment of potential future health effects. That report also highlighted the anticipated health impacts by major geographic region. The fourth assessment report not only devotes a whole chapter to human health, but also has references to health throughout the report. In 1996, the World Health Organization (WHO), recognized for the first time the challenges posed to human health by climate change and the World Health Assembly endorsed collaboration with other agencies in further identifying the problem. More than 10 years have passed since then and a growing body of research and assessment has been made available worldwide. Knowledge concerning the observed health impacts of climate change in Europe derive from European studies (ACACIA, cCASHh, PHEWE, ENSEMBLES, EDEN), national climate change health impact assessments and studies carried out by several national research councils or agencies. These studies quantified the effects of weather and climate variability on health, pointed out early impacts on human health, estimated some of the future burden of disease and provided some idea of potential future risks.
1.2 The attribution of health effects to climate change
The challenges in identifying, quantifying and predicting the health impacts of climate change entail issues of scale, “exposure” specification and the elaboration of often complex and indirect causal pathways. First, the geographic scale of climate-related health impacts and the typically wide time spans are unfamiliar to most researchers. Epidemiologists usually study problems that are geographically localized, have relatively rapid onset and directly affect health. The individual is usually the natural unit of observation and causal thinking focuses on specific directly acting (“downstream”) factors. Second, the “exposure” variable – comprising weather, climate variability and climate trends – poses difficulties. There is no obvious "unexposed" group to act as baseline for comparison. Indeed, because there is little difference in weather/climate exposures between individuals in the same geographic locale, comparing sets of persons with different “exposures” is precluded. Rather, whole communities or populations must be compared – and, in so doing, attention must be paid to inter-community differences in vulnerability. For example, the excess death rate during the severe 2003 heat-wave varied greatly across cities and countries, because of differences in factors such as housing quality and health care preparedness. Third, some health impacts occur via indirect and complex pathways. For example, the effects of temperature extremes on health are direct, whereas the effects of changes in temperature and cloud cover on diseases related to air pollution involve several intermediate steps. More complex
4
still, changes in the composition and functioning of the ecosystem help mediate the impact of climatic change on transmission of vector-borne infectious diseases and on agricultural productivity. A final challenge is the need to estimate health risks in relation to future climatic/environmental scenarios. Unlike most recognized environmental health hazards, much of the anticipated risk from global climate change lies years to decades into the future. Therefore, the best estimation of the future health effects of climate change will necessarily come from modelling based on current understanding of the effects of climate (not weather) variation on health from observations made in the present and recent past, acknowledging the influence of a large range of mediating factors (Ezzatti et al., 2004). These models are associated with substantial uncertainties. For assessing the impacts of climate change on Italian populations, the authors applied the WHO guidance provided in “Methods of assessing human health vulnerability and public health adaptation to climate change” (WHO Regional Office for Europe, 2003). The assessment is basic: reviewing the literature and seeking expert advice. Due to the paucity of information on the attribution of health effects to climate change in Italy, grey literature was also included (books, national assessments and reports, agency reports, etc.), as well as international or European studies that refer to Italy. Box 1 shows the search strategy used. Box 1: Search strategy • Internet: using keywords in English and Italian (e.g. “climate change and health”,
“cambiamento climatico e salute”); review of references in key documents. • MEDLINE, PubMed and WHO databases: keywords were climate change, extreme events, heat-
waves, flooding, air pollution, health, Europe, Italy and specific diseases (heat stroke, respiratory diseases, foodborne diseases, Salmonella, vector-borne diseases). Literature older than five years was excluded when more than fifty items were found in one search.
• The following climate hazards were taken into consideration: heat, cold, air pollution, heavy precipitation, disaster (landslide, flooding) and the following health outcomes identified for Italy: mortality due to heat, mortality and morbidity due to flooding and morbidity due to food- and vector-borne diseases.
• Inclusion criteria: all articles that included two or more key words. Epidemiological studies with low sample sizes were excluded. Where review articles were available, this is referred to.
1.3 The framework used in this assessment
As in other areas, populations in Italy are exposed to an increasing frequency and intensity of extreme events and weather variability and also to long-term changes in mean temperature and precipitation. These exposures either affect health directly or are associated with a number of changes in sectors and systems (such as water, agriculture, energy, etc.) that are important determinants of human health. There are many other determinants of health that may or may not be affected by the changing climate, such as health care infrastructure. The observations of the last decades show that impacts vary significantly by location and by population across Europe. Annual variability and multiple exposures may lead to enhanced effects, although we know little about this. The actual future impacts on human health will very much depend on the character, magnitude, and rate of climate variation to which “health” is exposed and the actual sensitivity and the ability of populations, governments and health systems to cope with the consequences. Figure 1 shows the different pathways of direct and indirect exposure taken into account in this
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assessment. These exposures and impacts will vary over time and will change with ongoing climatic changes. Figure 1: Pathways by which climate change affects human health in Italy
Direct exposures temperature, precipitation, extremes
Indirect exposures water, agriculture, ecosystems, tourism, energy, air quality, etc.
Health impacts
Heat-related mortality and morbidity
Cardiorespiratory diseases from air pollution
Allergic disorders
Increase in injuries, deaths and morbidity from floods and fires
Changes in distribution of the range of vector-borne diseases
Increase in attributable burden of water- and food- borne diseases
Climate change
Environmental conditions
Socioeconomic conditions
Health systems
Source: adapted from Confalonieri et al., 2007
1.4 Content of this publication
Chapter 1 gives an overview of the current knowledge on climate change and health effects globally and Chapter 2 highlights observed and projected climate change with a focus on Italy. For each subcategory, the evidence from the global and European levels is summarized then scaled down to the national Italian level. In Chapter 3 the associated impacts on systems and sectors are described. Sectors were selected based on their relevance to human health and their potential indirect effects on human health. Chapter 4 describes the evidence of observed and potential health impacts, Chapter 5 describes mitigation and adaptation actions and Chapter 6 lists the conclusions of this work. With this publication the authors provide a comprehensive overview of the current knowledge on climate change and variability in Italy for the interested public and in particular for environment and health professionals, decision makers and stakeholders. The collection of evidence, but also the identification of data gaps and research needs, can be used to support decisions when setting priorities. Despite a remaining level of uncertainty for future scenarios, the negative effects of the changing climate are already visible and the threats are too dangerous to defer action. In addition, the mitigation and adaptation options have a range of positive side-effects and should be integrated into everyday policies and action at all levels.
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2. Climate change and variability in Italy
– by Antonio Navarra, Franco Desiato, Domenico Gaudioso, Andrea Toreti and Tanja Wolf The Earth’s climate is determined by complex interactions between the Sun, oceans, atmosphere, cryosphere, land surface and biosphere. The Sun is the principal driving force for weather and climate. The uneven heating of the Earth’s surface (being greater nearer the equator) causes great convection flows in both the atmosphere and oceans, and is thus a major cause of winds and ocean currents. Five concentric layers of atmosphere surround this planet. The lowest layer (troposphere) extends from ground level to around 10–12 km altitude on average. The weather that affects the Earth’s surface develops within the troposphere. The next major layer (stratosphere) extends to about 50 km above the surface. The ozone within the stratosphere absorbs most of the Sun’s higher-energy ultraviolet rays. Above the stratosphere
are three more layers: the mesosphere, thermosphere and exosphere. Overall, these five layers of the atmosphere approximately halve the amount of incoming solar radiation that reaches the Earth’s surface. In particular, certain “greenhouse” gases, present as trace concentrations in the troposphere (and including water vapour, carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), halocarbons, and ozone) absorb about 17% of the solar energy passing through it. Of the solar energy that reaches the Earth’s surface, much is absorbed and reradiated as long- wave (infrared) radiation. Some of this outgoing infrared radiation is absorbed by greenhouse gases in the lower atmosphere, which causes further warming of the Earth’s surface. This supplementary warming process is called “the greenhouse effect”. Human-induced increases in the atmospheric concentration of greenhouse gases are amplifying the greenhouse effect. Greenhouse gas emissions of CO2, CH4 and N2O are the highest ever observed in the last 650 000 years, and it is very likely that greenhouse gas forcing is the dominant cause of observed warming of this century (Alley et al., 2007). Globally we can observe a significant change in numerous climatic parameters. Changing temperatures, extremes and precipitation can directly affect human health, as outlined in Figure 1. Also, Italy has contributed to the increases of greenhouse gases worldwide. This chapter looks at Italy’s share of emissions, shows the observed changes in Italy as regards the environment and human health and indicates what the future projected changes for Italy may look like.
2.1 Italy’s contribution to climate change
Following standardized methods and designated communication structures, national authorities produce the database of national atmospheric emissions. This national emissions inventory collects the data on emissions of greenhouse gases as well as emissions of acid and eutrophic substances, tropospheric ozone precursors, benzene, particles, heavy metals, polycyclic hydrocarbons, dioxins and many more. These data show that between 1990 (“base year”) and 2005 the total greenhouse gas emissions in Italy increased by 12.1% (in CO2 equivalent, excluding emissions and removals of
Key messages • Between 1990 and 2005 the
total greenhouse gas emissions in Italy increased by 12.1%.
• The energy industries (32%) and transport (26%) are the main contributors to CO2 emission.
• Italy is not yet succeeding in reducing national greenhouse gas emissions by 6.5% of the base level of 1990.
7
CO2 from land use change) from 519.5 to 582.2 million CO2 equivalent metric tons. The emissions and their increase is largely (90%) attributed to emissions of CO2 rather than to the other greenhouse gases (see Figure 2). Splitting the CO2 emissions up into the sectors as suggested by the UNFCCC, we see that most CO2 emissions (94%) and their increase stem from the energy sector (see Figure 3). In the energy sector, energy industries (32%) and transport (26%) are main contributors to CO2 emission (see Figure 4). Other greenhouse gases like CH4 and N2O accounted for 6.9% and 7.4%, respectively, of the total greenhouse gas emissions in 2005. CH4 emissions decreased by 4.3% from 1990 to 2005, while N2O increased by 5.8%. Other greenhouse gases, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6), ranged from 0.3% to 1% of total emissions; at present, variations in these gases are not relevant to reaching the objectives for emissions reduction (see Figure 2) (APAT, 2007a; Romano et al., 2005). Figure 2: Trend in greenhouse gas emissions in Italy, by gas
0
50
100
150
200
250
300
350
400
450
500
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
C O
2 e
q .
(M t)
e x
c lu
d in
g L
U L
U C
F CO2 CH4 N2O HFCs, PFCs, SF6
Source: APAT, 2007a
Figure 3: Trend in greenhouse gas emissions in Italy, by sector
-140
-40
60
160
260
360
460
560
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
C O
2 e
q . (M
t)
Energy Industrial Processes
Agriculture Waste
Use of solvents LULUCF
Source: APAT, 2007a
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Figure 4: Sources of CO2 emission in the energy sector
34%
18%
27%
20% 1% Energy industries
Manufacturing industries
Transport
Tertiary and residential
Other
Source: APAT, 2007a
In the context of the UNFCCC and the Kyoto Protocol, during the period 2008–2012 Italy is obliged to reduce national greenhouse gas emissions by 6.5% of the base level of 1990. Italy is far from succeeding in this aim. Emissions have been constantly increasing since 1997, although between 2004 and 2005 the increase rate was limited to 0.3% per year (APAT, 2007a). In a recent report, the European Environment Agency (EEA) said that as well as Belgium, Denmark, Ireland, Spain, Austria and Portugal, Italy too was not on track with regard to greenhouse gas emissions in 2004 and projects that it will miss the Kyoto targets despite the implementation of additional measures, the use of Kyoto mechanisms or the use of carbon sinks (EEA, 2006). The emission of about 580 million CO2 equivalent metric tons of greenhouse gases in Italy corresponds to 11.2% of the 5200 million metric tons in Europe and 2.1% of the global 27 560 million.
2.2 Observed climate
change in Italy
2.2.1 Trends in temperature and
precipitation
At global level, the IPCC has found that 11 of the last 12 years (1995–2006) rank among the 12 warmest years in the instrumental record of global surface temperature (since 1850). The updated 100-year linear trend (1906 to 2005) of 0.74°C (+- 0.18°C) is therefore larger than the corresponding trend for 1901 to 2000 given in the third assessment report of 0.6°C (+- 0.2°C). The linear warming trend over the last 50 years (0.13°C +- 0.03°C per decade) is nearly twice that for the last 100 years. The total temperature increase from 1850–1899 to 2001–2005 is 0.76°C (+- 0.19°C) (Alley et al., 2007). In Europe, studies concerning climate trends have been undertaken at various locations. However, results from these are not directly comparable
Key messages Italy has already observed: • an increase in maximum temperature
by 0.6°C in the north, and by 0.8°C in the centre-south over the last 50 years;
• a progressive reduction in precipitation since 1930, and, consequently, an increase in aridity;
• a decrease in precipitation between 1951 and 1996 of 14% throughout the country but most significantly in the centre and in the south;
• a rise in precipitation intensity both in the northern and southern regions;
• a more rapidly increasing number of tropical nights between 1981 and 2004; in the whole period, a net increase of about 14% of summer days has been estimated;
• a variation of -0.25 of frost days per year between 1961 and 2004, corresponding to an average reduction of about 20% of the number of frost days over 43 years.
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because of inconsistencies in data set length and quality and the different methods used for data processing and trend analysis (Wijngaard, Tank and Konnen, 2003). Nevertheless, some common patterns appear to be emerging. For most locations across Europe, increases in minimum temperature appear to be greater than in maximum temperature (Klein Tank, Wijngaard & van Engelen, 2002) and in many cases this has been attributed to increasing nocturnal cloud cover (Brazdil et al., 1996; Huth, Kysely & Pokorna, 2000; Wibig & Glowicki, 2002). In Italy, a time series analysis from 1865 to 1996 of about 40 meteorological stations showed that monthly maximum and minimum temperature increases differ from the north to the centre-south. In the north, maximum temperatures increased by 0.6°C and by 0.8°C in the centre-south. Minimum temperatures increased by 0.4°C in the north and 0.7°C in the centre-south during the considered period. From 1930 on, both in the centre and in the south of Italy, in addition to these temperature increases, a progressive reduction in precipitation and, consequently, an increase in aridity have been recorded. The trend in temperature and precipitation as given in Figure 5 shows an inverse correlation. The graphs represent five year moving averages of temperature (solid line) and precipitation (histogram) anomalies. It demonstrates the increase in temperature (0.7°C per century for the north and 0.9°C per century for the south of Italy) and a decrease of precipitation for the same areas (Brunetti et al., 2000b; Brunetti et al., 2001; Buffoni, Maugeri & Nanni, 1999). In addition to precipitation totals, changes in precipitation intensity are also important because of implications for flooding and soil erosion. Some studies point to intensity increases being associated with certain types of weather system (Widmann & Schar, 1997) and the changing relationships between wet day occurrence and wet day rainfall totals (Brunetti, Maugeri & Nanni, 2000, 2001). For the European Alpine region precipitation intensity has increased and is more marked for the winter months (Frei & Schar, 2001). An Italian analysis of precipitation data gathered during the period of time 1951–1996 showed that precipitation decreased all over the national territory during the considered period, but most significantly in the centre and in the south. The reduction in rainy days throughout the national territory (about 14% both in the north and in the south) is statistically significant; greater reductions have been observed in wintertime. A rise in precipitation intensity has also been observed in both the northern and the southern regions; in the northern regions the persistence of dry periods increases in wintertime and in the southern regions in summertime (Brunetti et al., 2000a, 2001; Brunetti, Maugeri & Nanni, 2001). These precipitation changes can be attributed both to variations in the atmospheric circulation and to an increase in atmospheric moisture as a consequence of local and global higher temperatures. The increase in precipitation intensity could be attributed to the intensification of the hydrologic cycle. Analysis of meteorological data available from 1950 up to 2000 in the Emilia Romagna region gave the following results: in summer, rainfall averages and precipitation extremes showed a significant positive trend; in autumn, no significant changes in average and extreme values were reported, with the exception of the average rainfall intensity for which a positive trend was observed; and in winter and spring a negative trend in the average volume of total rainfall was recorded (Tomozeiu et al., 2000; Tomozeiu, Busuioc & Stefan, 2002; Tomozeiu, Lazzeri & Cacciamani, 2002). Another study in the same region showed an increase of the rainfall average intensity during the autumn season (Cacciamani et al., 2000). A recent analysis of climate trends in the Veneto region during the last 4–5 decades highlighted increases in temperatures (both minimum and maximum values), an increase in autumnal rainfall, an increase in the frequency of extreme events (such as unusually strong rain or strong thermal variation between seasons) and a decrease in winter rainfall (Monai, 2004).
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Figure 5: Five year moving average temperature and precipitation anomalies
Note: temperature: solid line; precipitation: histogram
Source: Brunetti, Maugeri & Nanni, 2000.
2.2.2 Trends in weather extremes
Extreme events are by definition rare stochastic events. Extreme weather events, such as extremely hot or cold temperatures directly affect human health (see Chapter 4). Others, such as rainfall in extreme quantity and frequency or strong wind, can cause or contribute to natural disasters: flooding and sometimes landslides often follow positive extremes in rainfall; drought is a consequence of negative extremes in rainfall and often leads to fires. In this section on observed trends in climate extremes, only the simple events like hot and cold days are tackled. The more
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complex extreme events such as drought and flooding are dealt with in the impact section (Chapter 3). At the global level the IPCC summarizes the recent trends (IPCC, 2007) as given in Table 1 below. In Europe, extreme temperatures will occur more frequently. The yearly maximum temperature is expected to increase much more in southern and central Europe than in northern Europe (Räisänen et al., 2004; Kjellström et al., 2004). In addition, Kjellström (2004) shows that in summer the warming of large parts of central, southern and eastern Europe may be more closely connected to higher temperatures on warm days than to a general warming, which means that extreme temperatures will be reached. A large increase is also expected for yearly minimum temperature in most of Europe, which in many locations exceeds the average winter warming by a factor of two to three. Much of the warming in winter is connected to higher temperatures on cold days, which indicates a decrease in winter temperature variability. An increase in the lowest winter temperatures, even if quite large, would primarily mean that current cold extremes would decrease. On the other hand, a large increase in the highest summer temperatures would expose Europeans to unprecedented high temperatures. Table 1: Recent trends for extreme weather events in the late 20th century
Phenomenon and direction of trend
Likelihood that trend occurred in late 20th century
Likelihood of a human
contribution to observed trend
Likelihood of future trend based on
projections for 21st century using SRES scenarios
Warmer and fewer cold days and nights over most land areas very likely likely virtually certain
Warmer and more frequent hot days and nights over most land areas very likely likely (nights) virtually certain
Warm spells/heat waves: frequency increases over most land areas likely more likely than
not very likely
Heavy precipitation events: frequency (or proportion of total rainfall from heavy falls) increases over most areas
likely more likely than not
very likely
Area affected by droughts increases likely in many regions since
1970s
more likely than not likely
Intense tropical cyclone activity increases
likely in some regions since
1970s
more likely than not
likely
Increased incidence of extreme high sea level (excludes tsunamis) likely more likely than
not likely
Source: IPCC, 2007
With regard to precipitation, Christensen and Christensen (2003), Giorgi, Bi & Pal (2004) and Kjellström (2004) all found a substantial increase in the intensity of daily precipitation events in Europe. This holds true even for areas with a decrease in mean precipitation, such as central Europe and the Mediterranean region during summer. It is associated with both changes in the number of wet days (decreasing for southern Europe) and changes in the amount of precipitation on wet days. The Mediterranean and even much of eastern Europe may experience an increase in dry periods by the late 21st century (Polemio, Casarano & Dragone, 2006).
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The combined effects of warmer temperatures and reduced mean summer precipitation would lead to more heat-waves and droughts. Schär et al. (2004) conclude that the future European summer climate would experience a pronounced increase in year-to-year variability and thus a higher incidence of heat-waves and droughts (see Figure 6). Beniston (2006) estimated that countries in central Europe would experience the same number of hot days as currently occur in southern Europe and that Mediterranean droughts would start earlier in the year and last longer. The regions most affected could be the southern Iberian Peninsula, the Alps, the eastern Adriatic seaboard and southern Greece. Although only the eastern Mediterranean currently has a regularly recurring dry period, the rest of the Mediterranean and even much of eastern Europe may also experience such periods by the late 21st century. According to Good et al. (2006), the longest yearly dry spell would increase by as much as 50%, especially over France and central Europe. However, there is some recent evidence (Lenderink et al., 2006) that these projections for droughts and heat-waves may be slightly overestimated due to the parameterization of soil moisture (soil storage capacity is limited, resulting in soil drying out easily) in regional climate models. There is more information on drought as an extreme event in Chapter 3. Figure 6: Characteristics of the summer 2003 heat-wave
Present
Notes: (a) June, July, August (JJA) temperature anomaly with respect to 1961–1990; (a)-(d) JJA temperatures for Switzerland observed during 1864- 2003; (b) simulated using an RCM for the period 1961-1990; (c) and simulated for 2071-2100 under the A2 scenario.
Source: adapted from Schär et al., 2004
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In Italy, several important indicators of climate change and variability may be derived from the statistical values of meteorological variables.1 For the assessment of the “frost days” and “hot days” events, three indices among those defined by the CCl/CLIVAR Working Group on Climate Change Detection (Peterson et al., 2001) have been used: the annual average number of frost days in Italy, that is, the number of days in a year with a daily minimum temperature of 0°C or below; the annual average number of tropical nights in Italy, that is, the number of days in a year with a daily minimum temperature greater than 20°C; and the annual average number of summer days in Italy, that is, the number of days in a year with a daily maximum temperature greater than 25°C (APAT, 2006b). The series of three indices was obtained from minimum and maximum daily temperatures measured by 49 synoptic stations of the Air Force Meteorological Service well distributed throughout Italian territory. These data series are quality checked and satisfy the basic requirements of completeness and continuity (Toreti & Desiato, 2006a, 2006b). Figure 7: Trend in summer days in Italy
0
20
40
60
80
100
120
19 61
19 65
19 69
19 73
19 77
19 81
19 85
19 89
19 93
19 97
20 01
20 05
d a y s
Source: APAT, 2007b.
Figure 7 shows the mean number of summer days in Italy from 1961 to 2005. The dashed line represents the normal value in the period 1961–1990. Based on a parametric statistical model for trend recognition, two trends may be distinguished. In the first, from 1961 until 1978, the number of summer days decreased, while from 1978 to 2004 it increased. Over the whole period, a net increase of about 14% of summer days is estimated. Figure 8 shows the mean number of tropical nights in Italy from 1961 until 2005. The dashed line represents the normal value in the period 1961–1990. Based on a parametric statistical model for trend recognition, two trends may be distinguished. In the first, from 1961 till 1981, the number of tropical nights decreases, while from 1981 till 2004 it increases at a faster rate. In the whole period, a net increase of about 50% of tropical nights is estimated. Figure 9 shows the mean number of frost days in Italy from 1961 to 2005. The dashed line represents the average in the period 1961–1990. Based on a parametric statistical model for trend recognition, a variation of - 0.25 frost days per year from 1961 to 2004 is estimated, corresponding to an average reduction of about 20% of the number of frost days over 43 years. These results show that the global trends observed in Europe also apply to Italy. This increases the probability that global and regional scenarios of climate change will be applicable to Italy as well.
1 Collected, calculated and diffused through the “Sistema nazionale per la raccolta, l’elaborazione e la diffusione di dati Climatologici di Interesse Ambientale” (SCIA) (www.scia.sinanet.apat.it), developed by APAT in collaboration with the Air Force Meteorological Service, the “Ufficio Centrale di Ecologia Agraria” and several regional environmental protection agencies (ARPA) (Desiato, Lena & Toreti, 2006).
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Figure 8: Trend in tropical nights in Italy
0
10
20
30
40
50
60
19 61
19 65
19 69
19 73
19 77
19 81
19 85
19 89
19 93
19 97
20 01
20 05
d a y s
Source: APAT, 2007b.
Figure 9: Trend in frost days in Italy
0
10
20
30
40
50
60
70
19 61
19 65
19 69
19 73
19 77
19 81
19 85
19 89
19 93
19 97
20 01
20 05
d a y s
Source: APAT, 2007b.
2.3 Scenarios of climate change for Europe
For Europe, overall climate projections are mostly based on the IPCC-SRES2 scenarios using the climate normal period (1961–1990) as a baseline and projecting to the year 2070. Box 2 explains some of the assumptions in these scenarios.
Box 2: The IPCC-SRES scenarios A1. The A1 storyline and scenario family describes a future world of very rapid economic growth, global population that peaks in mid-century and declines thereafter, and the rapid introduction of new and more efficient technologies. Major underlying themes are convergence among regions, capacity building and increased cultural and social interactions, with a substantial reduction in regional differences in per capita income. The A1 scenario family develops into three groups that describe alternative directions of technological change in the energy system. The three A1 groups are distinguished by their technological emphasis: fossil-intensive (A1FI), non-fossil energy sources (A1T) or a balance across all sources (A1B) (where balanced is defined as not relying too heavily on one particular energy source, on the assumption that similar improvement rates apply to all energy supply and end use technologies). A2. The A2 storyline and scenario family describes a very heterogeneous world. The underlying theme is self-reliance and preservation of local identities. Fertility patterns across regions converge very slowly, which results in continuously
2 SRES: special report on emission scenarios.
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increasing population. Economic development is primarily regionally oriented and per capita economic growth and technological change more fragmented and slower than other storylines. B1. The B1 storyline and scenario family describes a convergent world with the same global population, that peaks in mid-century and declines thereafter, as in the A1 storyline, but with rapid change in economic structures toward a service and information economy, with reductions in material intensity and the introduction of clean and resource- efficient technologies. The emphasis is on global solutions to economic, social and environmental sustainability, including improved equity, but without additional climate initiatives. B2. The B2 storyline and scenario family describes a world in which the emphasis is on local solutions to economic, social and environmental sustainability. It is a world with continuously increasing global population, at a rate lower than A2, intermediate levels of economic development, and less rapid and more diverse technological change than in the B1 and A1 storylines. While the scenario is also oriented towards environmental protection and social equity, it focuses on local and regional levels. All scenarios should be considered equally sound. The SRES scenarios do not include additional climate initiatives, which means that no scenarios are included that explicitly assume implementation of the United Nations Framework Convention on Climate Change or the emissions targets of the Kyoto Protocol. Source: IPCC, 2000
In the future, it is very likely that the following changes will occur within this century in the Mediterranean and Europe: a higher than average increase in the highest temperatures in southern Europe; an annual decrease in precipitation in most of the Mediterranean area; a decrease in the annual number of precipitation days in the Mediterranean area; and a decrease in snow season and depth. Following both the A2 and B2 scenarios, Europe will experience a warming in all seasons (in A2: 2.5% to 5.5°C; B2: 1% to 4°C; the range of change is related to emission scenarios and different climate modelling results). The warming is greatest over eastern Europe in December-January-February and over western and southern Europe in June/July/August (Giorgi, Bi & Pal, 2004). Results using two regional climate models under the PRUDENCE project show a greater warming in winter than in summer in northern Europe and the reverse in southern and central Europe. A very large increase in summer temperatures is shown to occur in the south- western parts of Europe (it exceeds 6°C in parts of France and the Iberian Peninsula) (Good et al., 2006; Kjellstrom, 2004; Räisänen et al., 2004). Figure 10: Multi-model averages and assessed ranges for surface warming
Source: IPCC, 2001
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With regard to precipitation, for all scenarios the mean annual precipitation decreases in southern Europe. But the change in precipitation varies substantially from season to season and across regions in response to changes in large-scale circulation and water vapour loading. Giorgi, Bi & Pal (2004) found that increased Atlantic cyclonic activity in December/January/February leads to enhanced precipitation (up to 15–30%) over much of western, northern and central Europe. Precipitation during this period decreases over Mediterranean Europe in response to increased anticyclonic circulation. Räisänen et al. (2004) found that summer precipitation decreases substantially (in some areas up to 70% in scenario A2) in southern and central Europe, and to a smaller degree in northern Europe up to central Scandinavia. Giorgi, Bi & Pal (2004) identified enhanced anticyclonic circulation in June/July/August over the north-eastern Atlantic which induces a ridge over western Europe and a trough over eastern Europe. This blocking structure deflects storms northward, causing a substantial and widespread decrease in precipitation (up to 30–45%) over the Mediterranean basin as well as in western and central Europe. Change in wind strength is highly sensitive to the differences in large-scale circulation that can result between different global models. From regional simulations based on ECHAM4,3 mean annual windiness increases over northern Europe by about 8% and decreases in Mediterranean Europe (Pryor, 2005; Räisänen et al., 2004). The increase for northern Europe is largest in winter and early spring, when the increase in the average north-south pressure gradient is largest. From regional simulations based on HadAM3H,4 change in windiness is small throughout Europe, and where it does occur it is mostly within the bounds of internal variability. For France and central Europe, all four of the simulations documented by Räisänen et al. (2004) indicate a slight increase in mean wind speeds in winter and some decrease in spring and autumn.
2.3.1 Projected increases of temperature in Italy
In addition to the regional projections for Europe, in Italy the Dynamic Climatology Group at the Istituto Nazionale di Geofisica developed a set of scenarios for the Mediterranean countries. The scenarios are based on the IPCC greenhouse gas emission scenarios SRES A2 and B2 (see Figure 10). The emission scenarios correspond to different assumptions about the socioeconomic evolution of the planet, but ultimately they are all based on the degree of concentration of greenhouse gases to be used in the climate model. Figure 11: Temperature change under scenario A2
Source: Gualdi & Navarra, 2006
3 Atmospheric general circulation model of the fourth generation, based on the weather forecast model of the European Centre for Medium-range Weather Forecasts (ECMWF) 4 High resolution global atmosphere model from the Hadley Centre.
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Figure 11 shows the expected surface temperature change in degrees under the scenario A2 for a reference period 2060–2070 in the 21st century with respect to a similar period in the 20th century (1980–1990) (Gualdi & Navarra, 2006). It is interesting to note that the pattern of warming in the summer in Figure 11 (left) has a strong resemblance to the warming pattern of the summer of 2003. It is, of course, impossible to attribute any single event to the general progressive evolution of the system, but the similarity is intriguing and it may bring some support to the speculation that the warming will manifest itself through an increase in the occurrence of events similar to those in the summer of 2003.
2.3.2 Projected precipitation changes in Italy
The changes in precipitation are shown in Figure 12 which visualizes the expected precipitation changes in mm/day under the scenario A2 for a reference period (2060–2070) in the 21st century with respect to a similar period in the 20th century (1980–1990). The differences between the scenario and the control are expressed in the same display format as in the previous picture. The differences are measured in mm/day of rain. There is a confused situation in summer when precipitation decreases everywhere except in a large area over the south of Italy and Albania. However, summer precipitation in the Mediterranean region is small and so we are looking at small differences in small numbers that are easily affected by chance or random variation. It is, instead, most interesting to inspect the winter precipitation in Figure 12, right. In this case we can see a definite and well-formed pattern. The precipitation decreases over the entire Mediterranean belt and we observe a corresponding increase in the precipitation in northern Europe. The magnitude is about 0.5 mm/day that corresponds to an accumulated amount over the 90 days of the season of 45 mm. The observed precipitation for winter in northern Italy is around 200 mm for the 90 days of winter. This means that we are facing a 25% possible decrease in precipitation by the late 21st century. B2 is a more optimistic scenario regarding the increase in the amount of CO2 and it accordingly generates a weaker greenhouse forcing. The changes follow the same general pattern as in the A2 case, but in a weaker and more disorganized form. Still, it is possible to recognize the distinctive pattern of warming and precipitation reduction evidences under A2. The expected precipitation changes in mm/day under the scenario B2 for a reference period (2060–2070) in the 21st century with respect to a similar period in the 20th century (1980–1990) is shown in Figure 13. The results obtained to date are certainly interesting, but the degree of reliability of the results of the simulations has to be evaluated. A reduction of 25% in winter precipitation is a major reason for concern. How can we believe this kind of result? It is, of course, a difficult and important question and there are no sure answers. In general, we can get a feel for the reliability of the model by checking the consistency of the simulation either internally or with other known results. The choice of the global model to perform the simulation offers an illuminating opportunity because we can investigate if the patterns that we have unveiled, and that we have inspected from a purely regional viewpoint, are part of something larger and more consistent. Figure 14 shows the expected global precipitation changes in mm/day under the scenario A2 for a reference period (2060–2070) in the 21st century with respect to a similar period in the 20th century (1980–1990). The differences are as discussed previously, but in this case we are showing them globally. Focusing on the winter precipitation (bottom panel) we can see several interesting patterns. The first observation is that the Mediterranean region is very small with respect to the Earth; very large changes are visible elsewhere and changes in the Mediterranean region do not particularly stand out. The second comment is that we can see that the changes we have discussed in the previous sections are indeed part of a larger system that extends from the Atlantic Ocean to Europe. It is composed of two parts: the northern branch is positive, indicating an increase in precipitation and the southern part is negative, indicating a decrease. It is the southern branch that ends up covering the entire Mediterranean region.
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Figure 12: Precipitation changes under scenario A2
Source: Gualdi & Navarra, 2006
Figure 13: Precipitation changes under scenario B2
Source: Gualdi & Navarra, 2006
The parallel strips of opposing features are the sign of a shift in the dominant trend of precipitation. According to these scenarios, later in the 21st century, rainfall will move north, leaving a deficit behind and a surplus in the new area. The loss of precipitation over the Mediterranean is part of a much larger change that involves the hemisphere. It is the border between the Hadley5 and the Ferrel cell6 that has shifted north making the descending and dry branch of the Hadley circulation a more frequent visitor to the Mediterranean and reducing rainfall. The fortunate state of equilibrium of the Mediterranean between north and south appears to be in danger. The observation that the change in the Mediterranean region is part of a bigger change
5 The Hadley cell is a circulation pattern that dominates the tropical atmosphere, with rising motion near the equator, poleward flow 10–15 km above the surface, descending motion in the subtropics, and a flow towards the equator near the surface. 6 The Ferrel cell is a secondary circulation feature, dependent for its existence on the Hadley cell and the Polar cell.
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therefore increases the reliability of the result, because the models are usually very good when dealing with extensive data that relate to a large geographical area. A similar argument can also be made for temperature. Figure 15 shows the expected global temperature changes in degrees under the scenario A2 for a reference period (2060–2070) in the 21st century with respect to a similar period in the 20th century (1980–1990). In this case the dominant effect is a general warming of the poles in winter and a general warming of the landmass in the summer and Europe is not an exception. Figure 14: Global precipitation changes under scenario A2
Source: Gualdi & Navarra, 2006
Figure 15: Global temperature changes under scenario A2
Source: Gualdi & Navarra, 2006
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3. Observed and projected impacts of climate
change and variability in Italy
The observed and projected changes in the climate system will affect the various sectors of the Earth’s systems in different ways. To look at the impacts on the different sectors separately is rather artificial as they are interlinked. However, for the sake of a better structure and understanding, the impacts are distinguished using the IPCC nomenclature. Accordingly, section 3.1 describes the impacts related to water; section 3.2 looks at the impacts on ecosystems, forests and agriculture; while section 3.3 outlines the impacts on urban environments and socioeconomic sectors. These impacts are all relevant to human health, as they may change exposure or intensify exposure, as illustrated in Figure 16. Figure 16: Direct and indirect exposure to climate change and human health
Direct exposures
temperature, precipitation, extremes
Indirect exposures
water, agriculture, ecosystems, tourism, energy, air quality, etc.
Health impacts
Heat-related mortality and morbidity
Cardiorespiratory diseases from air pollution
Increase in injuries, deaths and morbidity from floods and fires
Allergic disorders
Changes in distribution of the range of vector-borne diseases
Increase in attributable burden of water- and food- borne diseases
Climate change
Environmental conditions
Socioeconomic conditions
Health systems
Mitigation, prevention and adaptation
Source: adapted from Confalonieri et al., 2007
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3.1 Water
– by Enzo Funari, Angiolo Martinelli, Monica Francesca Blasi, Mario Carere, Valentina Della Bella, Laura Mancini,
Stefania Marcheggiani, Francesco Mattera, Mara Stefanelli
In this section on impacts related to water, several groups of impacts on systems are presented. They range from water stress to impacts on recreational waters, coastal flooding from sea level rise, river flooding and droughts.
3.1.1 Water stress
Observations and projections based on various scenarios and Global Circulation Models (GCMs) show that water flow is decreasing in some regions of Europe and will further decrease in the future (Chang et al., 2002; Etchevers et al., 2002; Iglesias, Estrela & Gallart, 2005; Menzel & Burger, 2002). Studies show a decrease in summer flows in the Alps (Schroter et al., 2005; Zierl & Bugmann, 2005). The volume of summer low flow may decrease by up to 50% in central Europe (Eckhardt & Ulbrich, 2003), and by up to 80% around the Mediterranean (Santos, Forbes & Moita, 2002). Therefore, the regions most prone to an increase in water stress are the Mediterranean (Portugal, Spain) and some parts of central and eastern Europe, where the 100-year deficit volumes may increase by 25% (Lehner et al., 2005) and the highest increase in irrigation water demand is forecast (Döll, 2002; Donevska & Dodeva, 2004; Santos, Forbes & Moita, 2002). Irrigation requirements are likely to become substantial in countries where they now hardly exist
(Holden et al., 2003). Demand for water for irrigation may be influenced by changes in the amount and distribution of agricultural land as affected in the future by the EU Common Agricultural Policy (CAP). Groundwater recharge may also be reduced (Eitzinger et al., 2003), with a larger reduction in valleys (Krüger, Ulbrich & Speth, 2002) and lowlands (e.g. in the Hungarian steppes) (Somlyódi, 2002). Figure 17 shows the annual change in river basin discharge between the baseline period (1961–1990) and two future time slices (2020s) and (2070s) as computed by the ECHAM4 and HadCM3 global climate models and the Baseline-A water use scenario (Lehner et al., 2005).
In many parts of Italy, particularly in the south, it has become ever more difficult to meet demand for water. The recent years of drought and the constant increase of water demand for the civil sector have made irrigation supply more problematic. Wastewater reuse could represent a viable solution to meet water demand. Planned exploitation of municipal wastewater could help to meet the demand for irrigation water, particularly in southern Italy (e.g. Sicily) where farmers have been practising uncontrolled wastewater reuse for a long time. Reuse of wastewater, however, may have consequences for human health if strict guidance is not applied. In northern and central Italy, where available water resources generally meet water needs for different purposes, wastewater reuse could play an important role in controlling the pollution of bodies of water. Several projects on wastewater reuse are currently in progress (Barbagallo, Cirelli & Indelicato, 2001).
Key messages • Water stress might increase
by 25% in this century, leading to higher demand for irrigation water.
• Safe water supply is becoming a social and economic emergency in several regions.
• Rises in sea level will put coastal areas and plains at risk of sea flooding.
• Heavy precipitation events could increase inland flooding.
• Higher marine water temperatures have allowed the migration and settlement of toxic algal species close to the Italian coasts; several health-related problems have been observed in summer.
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Figure 17: Annual change in river basin discharge
Source: Lehner et al., 2005
3.1.2 Droughts and desertification
Changes in the water cycle are likely to increase the risk of drought. Drought is defined as a period of below average precipitation that adversely affects gross primary productivity and causes water scarcity. The most important effect of drought is on agriculture and soil quality. Extended droughts in fact make soil more vulnerable to soil erosion and desertification. Food production may also be affected as demonstrated by the heat-wave which occurred in 2003. This was associated with annual precipitation deficits of up to 300 mm, and drought was a major contributor to the estimated 30% fall in gross primary land-related production in Europe (Ciais et al., 2005). This reduced agricultural productivity and increased production costs, with an estimated loss of more than € 11 billion (Olesen & Bindi, 2003). The risk of drought is likely to increase in southern and central Europe. Several model studies have indicated a decrease in the number of precipitation days (e.g. Semenov, Gelver &Yasyukevich, 2002; Voss, May & Roeckner, 2002; Räisänen et al., 2004; Frei et al., 2006) and an increase in the length of the longest dry spells in this area (Voss, May & Roeckner, 2002; Pal, Giorgi & Bi, 2004; Beniston, 2006; Tebaldi et al., 2006). The decrease in precipitation together with enhanced evaporation in spring and early summer is very likely to lead to reduced summer soil moisture in the Mediterranean region and parts of central Europe (e.g. Douville et al., 2002). Drought can increase the risk of soil erosion and desertification. This is quite common in many countries since inappropriate land use and groundwater extraction increase the vulnerability of soils. Climate change is expected to affect the desertification process by increasing the intensity of rainfall, which will accentuate water loss due to run-off and erosion; by increasing evapotranspiration, causing soil salinization; by increasing aridity, which will contribute to reducing concentrations of organic matter in the soil; and by increasing droughts, which will jeopardize many anthropic activities (see Figure 18). However, scientists cannot yet predict how rising atmospheric levels of greenhouse gases will affect the global rate of desertification. What they can predict is that changes in temperature, evaporation and rainfall will vary from region to region. As
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a result, desertification is likely to be aggravated in some critical areas, in particular in the Mediterranean basin.7 In Italy, aridity has increased in the course of the 20th century in the southern and island regions both in terms of an increase in the number of areas involved and in terms of the index values. Arid, semi-arid and dry sub-humid areas currently include major regions in the south of Italy, such as Sicily, Sardinia, Apulia and Basilicata. At the same time, the mistaken conception and implementation of several policies intended to support agriculture – the use of inappropriate water resources for irrigation purposes, forest fires – and the increased urbanization of coastal areas have all contributed to a slow depletion of the soil resources, both quantitatively and qualitatively. Figure 18: Logic framework for desertification
Causes of desertification
natural human
Climatic variation: precipitation reduction, temperature increase Drought: lack of water for ecosystems and productive activity Soil erosion from intense rainfall
Water resources: unsustainable use of surface water and groundwater Fire: destruction of plants and animals, negative effects to soil quality Agriculture: inappropriate use of land practices and machines, intense pasture Urbanization: soil sealing Tourism: unplanned land use for infrastructure and buildings Discharge of contaminants and extraction of soil
Other factors:
soil types, morphology, hydrology, sensitive ecosystems, little vegetation coverage and more
Processes of degradation:
• Soil erosion • Loss of organic material • Salination • Contamination and pollution • Loss of biodiversity
Source: adapted from Sciortino et al., 2000.
3.1.3 Sea level rise and coastal flooding
The vulnerability of coastal shelf waters and some stretches of coastline to sea level rise and coastal flooding are dependent on several local factors (Duffy & Devoy, 1998; EEA, 2004a, 2004b; Smith et al., 2000; Swift et al., 2005). For example, will low-lying coastlines with high population densities and small tidal ranges be most vulnerable to sea level rise (Kundzewicz & Parry, 2001)? Coastal flooding related to sea level rise could affect large populations in Europe overall (Arnell et al., 2004). Under the A1FI SRES scenario up to 2.5 million people each year might experience coastal flooding in Europe by 2080 (Nicholls, 2004). Approximately 20% of existing coastal wetlands may disappear by 2080 under SRES scenarios for sea level rise in Europe (Devoy, in press; Nicholls, 2004). Impacts of sea level rise and related climate warming on coastal marine ecosystems are also likely to intensify problems of eutrophication and stress on biological systems (EEA, 2003, 2004b, 2005a; Robinson et al., 2005). Furthermore, in areas of coastal subsidence or high tectonic activity, as in the low tidal range of the Mediterranean and Black Sea regions,
7 In the context of the DISMED project, an index to assess vulnerability to desertification has been developed and applied to countries in the Mediterranean. A map of areas at risk of desertification can be viewed under http://www.ibimet.cnr.it/Case/dismed_products.php and indicates that southern Italy and the islands of Sicily and Sardinia are particularly at risk of desertification.
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climate-related sea level rise could significantly increase potential damage from storm surges and tsunamis (Gregory et al., 2001). However, experiments indicate a decline in storminess and wind intensity eastwards into the Mediterranean (Busuioc, Chen & Hellstrom, 2001; Tomozeiu, Stefan & Busuioc, in press), but with localized increased storminess in parts of the Adriatic, Aegean and Black seas (Guedes Soares et al., 2002). For the Italian coasts sea level rise will imply high risks. About 4500 km2 of coastal areas and plains would be at risk of coastal flooding (according to a study carried out by NASA-GISS); floods might occur in northern Italy (Upper Adriatic Sea), central Italy (the coastline between Ancona and Pescara, the coasts near Rome and Naples) and in southern Italy (Gulf of Manfredonia, coasts between Taranto and Brindisi, eastern- southern Sicily).
3.1.4 Heavy rainfall and river flooding
Changes in the water cycle are likely to increase the risk of floods. An increase in intensive short- term precipitation in most of Europe is likely to lead to an increased risk of flash floods (EEA, 2004b), particularly in the Mediterranean and eastern Europe (Ludwig et al., 2003). Nevertheless, the flood risk from climate change could be magnified by an increasing impermeable surface due to urbanization (de Roo et al., 2003) and modified by changes in vegetation cover (Robinson et al., 2003) in small catchments. Figure 19: Regions of Italy: risks of flooding and landslides
Source: WHO with data from APAT, 2004b In Italy, records suggest that floods and droughts have been more frequent over the past 50 years. The flooding risk in Italy is high and widespread especially because of its peculiar geological and geomorphological formation with young orographical features. Some areas of Italy are subject
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to subsidence, which further increases this risk. Subsidence is a geological phenomenon characterized by the sinking of the land. In Italy, it has increased over recent years as a consequence of human activities, especially excessive groundwater withdrawal. In the eastern Po plain in northern Italy, the recent effects of human activities on subsidence have been judged to be as great as those resulting from long-term natural processes. A clear correlation between flood frequency and rapid subsidence can also be demonstrated (Carminati & Martinelli, 2002). A technical report by the Ministry of the Environment and Land Protection (Ministero dell'Ambiente, 2000) quantifies the areas with high risk of flooding: they cover an area of 7774 km², corresponding to 2.6% of the national territory. Floods can have severe consequences for human health, infrastructures and the environment. The most dramatic floods in Italy occurred in the Po (1951, 1994 and 2000) and Arno river basins (1966). Table 2 shows the main floods recorded in Italy from 1951 to 2003 as summarized by APAT.8 Heavy rainfall also causes landslides. Figure 19 summarizes information on percentages of regional surfaces at risk of flooding and at risk of landslides for the regions of Italy (APAT, 2004a, 2004b). Information on the regional population density is added. It shows that Lombardia and Campania have high average population densities of more than 300 persons per square kilometre and at the same time a relatively big share of land surface is at risk of flooding (4–6% of the regional surface) and landslides (9–20% for Campania, 4–8% for Lombardia). Table 2: Main floods in Italy
Loss of human lives
Estimated total
damage
Estimated total damage
/GDP*
Event period Region
n Million € %
1951 16–22 October Calabria, Sicily, Sardinia 110 15.49 0.2791
1951 8–12 November Piedmont, Lombardia, Veneto, Liguria, Emilia Romagna
100 206.58 3.7216
1953 21 October Calabria 100 - - 1954 26 October Campania 318 23.24 0.3295 1966 3–5 November Piedmont, Lombardia, Trentino Alto
Adige, Veneto, Friuli Venezia Giulia, Liguria, Tuscany ,Lazio, Sardinia
118 516.56 2.5107
1968 2–4 November Piedmont 74 154.04 0.6418 1976 5 November Sicily 18 51.65 0.0571 1978 6–10 August Piedmont 18 51.65 0.0400 1983 3–11 September Piedmont, Lombardia, Friuli Venezia
Giulia 6 154.94 0.0474
1987 18 July – 28 August Lombardia 53 1 549.37 0.3047 1991 12 October Tuscany, Sicily 12 77.47 0.0104 1991 19 October Lazio 3 - - 1994 3–6 November Piedmont 64 2 840.51 0.3326 1996 18–19 June Tuscany 21 200.00 0.0204 1996 14 October Calabria 6 113.62 0.0116 2000 14–16 October Piedmont, Valle d'Aosta, Lombardia,
Liguria 37 2 582.28 0.2214
2001 13–16 September Campania 2 165.27 0.0136 2002 14 November,
7 December Piedmont, Lombardia, Veneto, Friuli Venezia Giulia, Liguria, Emilia Romagna
2 850.00 0.0674
2003 23–26 January Abruzzo, Molise, Campania, Puglia 1 810.00 0.0623
* Gross Domestic Product Source: APAT, 2004b
8 Based on information from ISTAT, GNR-GNDCI AVI Project, ARPA Piedmont, SICI, Benedettini and Gisotti “il dissesto idrogeologico”, FLANET, Nimbuswd, EM-Dat: the OFDA/CRED International Disaster Database; Scienza e Tecnica, year LXVI – No. 393 – May 2003, Centro studi per la flora mediterranea-Borgo Val di taro (Parma), l’alluvione del fiume Taro nel November 1982; commissione interministeriale per lo studio della sistemazione idraulica e della difesa del suolo, l’evento alluvionale del novembre 1966; CONACEM.
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3.1.5 Recreational waters
In this section on recreational waters, two impacts with health implications are outlined: first structural changes in lakes in Italy and second the problem of toxic marine algae. With regard to lakes, studies that have been conducted provide evidence that increased atmospheric temperature has had an impact on Italian lakes – those in the Alps but also those in the rest of Italy. Increased temperature causes a thermoenergetic increase in the surface waters and the deep water of the lakes and influences the annual and long-term circulation and mixing of water in the lakes, especially in late summer when the thermal inversion occurs. There is less mixing of water in the lakes and this decreases the availability of oxygen in the deep water. Under anoxic conditions the mineralization of organic substances is impaired or slowed down and the risk of anaerobic processes and the release of methane and CO2 increases. A lack of oxygen in deep waters also enhances the mobilization of metals and of nutrients (e.g. phosphorous), which leads to an excessive growth of algae, cyanobacteria (see Chapter 4) and to eutrophic problems in the lake’s ecosystem. The changes in water quality also affect human activity and human health as described in Chapter 4. These effects have been observed at Lake Maggiore, Lake Garda, Lake Orta, Lake Como (Ambrosetti & Barbanti, 1999), Lake Iseo (Garibaldi et al., 1999) and Lake Bolsena (Bruni, 1998). In order to monitor these changes, time series analysis of important indicators such as algae biomass and chlorophyll are necessary. Regarding toxic marine algae, the observation of a rise in the Mediterranean Sea temperatures since the 1980s is relevant. In June and July 2003, sea surface temperatures reached particularly high values of 28°C with peaks of 32°C.9 Some tropical species have colonized the Mediterranean Sea coming from other seas through the Suez Canal, the Strait of Gibraltar (www.ipsema.it) and ships’ ballast water (Carlton & Geller, 1993). Several toxic algal species live in the Mediterranean Sea (Ade, Funari & Poletti, 2003). Recently, some tropical ichthyotoxic species have also been found in Italian marine environments. Some of them, Heterosigma akashiwo, Chattonella antiqua, Chattonella marina, Fibrocapsa japonica (all Raphidophyceae) produce toxins of the brevetoxin group (Mattei & Bruno, 2005). In addition, in recent years, several Italian coastal stretches have seen the occurrence of Ostreopsis ovata, a marine dinoflagellate species (Gallitelli et al., 2005; Sansoni et al., 2003). It is a benthic species which lives on red and brown macroalgae in tropical or subtropical regions. Some Ostreopsis strains produce palytoxin and analogues which can accumulate in fish and are implicated in clupeotoxism associated with eating clupeoid fish (Onuma et al., 1999). Palytoxin is one of the most potent non-peptidic marine toxins. It has a lethal dose in 50% of rats, mice, dogs and monkeys, when given intravenously, at ranges between 0.03 and 0.45µg/kg; palytoxin causes cytolysis as a result of the inhibition of Na+, K+-ATPase (Tosteson, 2000). It has been recognized as the causative agent of fatal human seafood poisoning (Onuma et al., 1999). Furthermore, during summer 2005, about 200 people who spent time on or near beaches in a stretch of the north-west Italian coast around the city of Genoa sought medical treatment for symptoms such as rhinorrhoea, cough, fever, bronchoconstriction with mild breathing difficulties, wheezing and, in a few cases, conjunctivitis. For almost all of these people, the symptoms stopped after a few hours and only 20 people were hospitalized (Brescianini et al., 2005, 2006). Ostreopsis ovata was deemed the possible causative agent; indeed during these same period this species was blooming in that particular beach area. It was hypothesized that these symptoms might be due to inhalation of aerosolized Ostreopsis ovata fragments. Analysis of the content of marine samples showed the occurrence of palytoxin in these algae (Penna et al., 2005).
9 See details under http://www.ipsema.it/natutes/natutes24/indice24.htm: Tarelletto Alessio Il Mediterraneo nuovo paradiso tropicale.
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On the basis of experience from 2005, an effective monitoring programme was conducted in 2006 in order to prevent dangerous exposure to Ostreopsis ovata blooms (see www.arpal.org). Similar but less intense episodes were observed in the Lazia and Puglia coasts in 2004 (Sansoni et al., 2003). This phenomenon is similar to that which occurs in the Gulf of Mexico where people exposed to marine aerosols during blooms of Karenia brevis suffer respiratory difficulty and irritation and burning of the throat and upper respiratory tract (Cheng et al., 2005). These examples show that the occurrence of new species in marine ecosystems is a health risk for humans.
3.2 Ecosystems, forests and agriculture
– by Lorenzo Cecchi, Simone Orlandini, Marco Morabito, Marco Bindi, Marco Morindo
There is strong evidence that the recent warming is noticeably affecting terrestrial biological systems, including such changes as the earlier timing of spring events. Also, satellite observations since the early 1980s show a trend in many regions towards earlier “greening” of vegetation in the spring linked to longer thermal growing seasons. There is also convincing evidence that observed changes in marine and freshwater biological systems are associated with rising water temperatures, as well as related changes in ice cover, salinity, oxygen levels and circulation. These include shifts in ranges and changes in algal, plankton and fish abundance in high- latitude oceans, increases in algal and zooplankton abundance in high-latitude and high-altitude lakes and range changes and earlier migrations of fish in rivers (Alley et al., 2007). Some examples are given in the following sections.
3.2.1 Phenology and allergenic plants
The timing of life-cycle events such as leaf unfolding, bird migration and egg laying and poleward and upward shifts in ranges of plant and animal species, is very sensitive to several climate variables, such as ambient temperature (Ahas, Jaagus & Aasa, 2000) or water availability (Peñuelas, Filella & Comas, 2002). Accordingly, the chronology of plants’ phenological phases is an indicator for checking if ecosystems are reacting to climate change. The analysis of historical data in the Mediterranean area shows that plant phenological development is more affected by temperature than rainfall (Gordo & Sanz, 2005). In general, in spring-flowering plants, the observed increasing temperature allows earlier leaf unfolding, flowering and fruit growing, while warmer autumn temperature conditions delay leaf fall, extending the leaf life-cycle (Frenguelli, 2002; Gordo & Sanz, 2005; Peñuelas, Filella & Comas, 2002). The increased plant-growing season is associated with a decreased probability of frost damage to young leaves and flowers since some long-term series analyses indicate a negative trend in the annual occurrence of frost days (Kostopoulou & Jones, 2005; Toreti & Desiato, 2006a, 2006b). Furthermore, recent studies have demonstrated the potential impact of climate change on allergenic plants and their pollen, which in this context are also called aeroallergens. The pollen season, pollen amount, pollen allergenicity and plant and pollen distribution (Beggs, 2004) depend
Key messages • Climate changes alters
characteristics of allergenic plants, biodiversity and mountainous ecosystems.
• Increased soil aridity and forest fires threaten Italian forests.
• Yield of summer crops might decrease due to development stages of extreme climate events.
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on the climate and react to changes in climate. First, the average length of the growing season in Europe has increased by 10 to 11 days over the last 30 years. Duration of the pollen season has also been extended, especially in summer and in late flowering species (Huynen et al., 2003). In addition, an earlier start and peak of the pollen season is more pronounced in species that start flowering earlier in the year (Corden, Millington & Mullins, 2003; Emberlin et al., 2002; Fitter & Fitter, 2002; Spieksma et al., 1995). Regarding the amount of pollen, there has been an increasing trend over the past decades which parallels local rises in temperature. Under experimental conditions substantial increases in pollen production resulted from exposure to increased CO2 concentration (Rogers et al., 2006; Wayne et al., 2002; Ziska & Caulfield, 2000). There is some evidence of stronger allergenicity in pollen from trees grown at increased temperatures (Ahlholm, Helander & Savolainen, 1998; Hjelmroos, Schumacher & Van Hage-Hamsten, 1995). Besides these trends, the changes in climate appear to have altered the spatial distribution of pollens. New patterns of atmospheric circulation over Europe might contribute to episodes of long-distance transport of allergenic pollen, increasing the risk of new sensitizations among allergic populations (Cecchi et al., 2006). There is growing evidence that climate change might also facilitate the geographical spread of particular plant species to new areas which become climatically adapted (see section 3.2.3.). Table 3 summarizes the possible effects of climate change on the most important allergenic plants in Italy. Present data suggest an increase in the pollen count and an earlier onset for all species; however, effects on grass pollen concentration might be mitigated by a change in land use (i.e. urbanization). Changes in allergenic plants may have consequences for allergic diseases (Riotte-Flandrois & Dechamp, 1995; Zanon, Chiodini & Berra, 2000). Table 3: Effect of warming on allergenic plants
Pollen Concentration Earlier onset
Birch ↑ yes
Grass ↔ yes
Pellitory ↑ yes
Ragweed ↑ yes
3.2.2 Animal species
Changing climate affects not only plants but also animals, and in particular species living in water. In general, the species richness in inland waters is highest in central Europe and declines towards the south and north because of periodic droughts and sal