Task 4.1: Impacts on natural environmental systems
Subtask 4.1.1: Running water ecosystems
University of Geneva, Switzerland [E. Castella, A. Lehmann]; University of Birmingham, UK [D. Hannah, A. Milner]
In mountain regions, climatic change is likely to alter the balance between water sources (rain, ice-melt, snowmelt, groundwater) - particularly modifying the amount and duration of snow cover and the magnitude and timing of peak ice-melt (Melack et al., 1997; Brown et al., 2005). Decreasing groundwater recharge and elevated water temperature could lead to disruption of flow permanency and to an increase of temporary stream stretches. In turn, modifications in primary determinants of the composition and diversity of the biota in mountain running waters can be expected (Brittain & Milner, 2001; Milner et al., 2001; Castella et al., 2001). In a changing climate with altered water source contributions, organisms are vulnerable and to avoid becoming extinct, they must either adapt physiologically and/or genetically, or migrate to more suitable habitats. As a result, invertebrate biodiversity is most likely to be affected through changes in species distribution. It remains to be investigated how reservoir management could be adapted to mitigate adverse changes in the parts of the catchments under their influence.
Despite the likelihood of such marked hydrological changes as snow packs and glaciers shrink (Barnett et al., 2005; Brown et al., 2007) our knowledge of how alpine aquatic ecosystems will respond is limited, regardless of the widely accepted importance of protecting freshwater ecosystem biodiversity (Ward and Tockner, 2001). To be successful, alpine river conservation strategies must be underpinned by a holistic understanding of the cascade of environmental processes, which ultimately determine biotic communities (Malard et al., 2006) as well as their response to future climate change and variability (Hannah et al., 2007).
Subtask 4.1.2: Mountain lake ecosystems
Alpine Wildlife Research Centre, Gran Paradiso National Park, Italy (A. von Hardenberg); Istituto per le Scienze dell’Atmosfera e del Clima (ISAC-CNR), Italy (A. Provenzale)
High-altitude alpine lakes are endangered ecosystems that are particularly sensitive to climate change (Skjelkvaele and Wright, 1998). Expected changes with a likely impact on ecosystems include ph shifts (Koenig et al. 1998), increased penetration of ultraviolet radiation due to decreased dissolved organic carbon and habitat reduction for cold stenothermic organisms due to warming (Schindler, 2001). In the Gran Paradiso National Park, 14 high altitude alpine lakes have been thoroughly monitored in 2006 and will be monitored again in 2007. The data collection program aims at estimating biodiversity indices and densities of zooplankton, zoo-benthos, nektonic macro-invertebrates, and amphibian and fish populations in these lakes.
The objectives of this ST are:
- To use data on physical parameters and benthic communities to develop models of high-altitude alpine lakes including the interaction between the biotic and abiotic components. One class of models will be based on deterministic equations for a multi-compartment ecosystem, coupled with simplified equations for the physical lake dynamics. The parameters and some of the functional forms of the interaction terms in these models will be directly estimated from the analysis of available data. A second type of models will be obtained from empirical fits to the data, and will include a significant stochastic component. Mixed deterministic-empirical models will also be developed.
- To use the generated models to understand and reproduce the similarities and differences between lake ecosystems (e.g., in terms of biodiversity, total biomass, connectivity) and to estimate alpine lake sensitivity to changes in physical parameters. The model inferences will be validated through a field campaign conducted during the project.
- To use data and model outputs to upscale the sensitivity of alpine lakes to environmental parameter variations and to assess the response of this type of aquatic ecosystems to different climate change scenarios. The blend of data analysis and model simulations will be used to identify the taxa that are best suitable as indicator species of potential biodiversity loss in high altitude lakes due to climatic change and to identify the most endangered components of high altitude lakes.
Task 4.2: Impacts on socio-economic systems
Subtask 4.2.1: Hydropower
CVA, Val D’Aosta, Italy [S. Juglair, E. Pucci]; CESI Ricerca, Italy [S. Maran]; ENEL, Italy [G. Galeati]; CUEPE, Univ. of Geneva, Switzerland [F. Romerio]
The project focus on the snow and ice dominated mountain areas and the detailed modelling of the snow and ice processes allows to carry out a detailed analysis of the impact of CC on hydropower systems. This ST will benefit of the simulation results from T 3.2 and ST 3.3.2, that will provide the streamflow regime in the future climate for the investigated pilot case studies, Rhone and Po.
The impact analysis will focus on the simulation of various operational scenarios of reservoir management, particularly addressing on the one hand the security of the electricity supply and, on the other hand, secondary targets such as flood protection, water supply or irrigation. These simulations will highlight the expected changes in terms of operational strategies as dictated by the modification of the temporal availability of melt-water. In addition, they will be combined with scenarios of future evolution of energy demand, which will be defined by means of both hypothetical scenarios or through specific targets simulated by energy demand models, which accounts for projections of population and economic growth and the evolution of the regulatory framework shaping trans-boundary energy trading.
The results of the impact analysis will be used to discuss how the consequences of the impact analysis will lead to an effective planning of capital investment in order to adapt hydropower systems to future water resources availability and to CC induced changes in the demand structure.
Additional investigations will address the impact on the hydropower sector arising by the need to cope with increased silting of reservoirs, as a consequence of the increase of denudated areas which are exposed to erosion because of glacier retreat; and the likely increased need for environmental flow requirements downstream of dams, as a consequence of the higher frequency of prolonged low flow periods and droughts.
These investigations will be carried out by means of a prototype of integrated model, which will be developed to estimate quantitatively the impact of the changes occurring in the physical system on the production and management. The application and demonstration of this model will be performed at the pilot sites and power plants both in the Rhone and Po river basins. The extension of the impact analysis to the regional and basin scale will be achieved by regionalization of the results from the reference case studies on the basis of hydropower plant size and of the magnitude of the changes of the streamflow regime, which will be available in a spatially explicit form over the entire river basin.
Subtask 4.2.2: Impacts of climatic and land use changes in water availability and management in the Mediterranean Mountains: The case of the Aragón river basin, Pyrenees.
Pyrenean Institute of Ecology, Spanish Research Council. Zaragoza, Spain. [J. I. Lopez, J. M. García-Ruiz, C. Martí-Bono, S. Beguería, S. M. Vicente-Serrano]
South-facing slopes of the Pyrenees play a major role in the hydrology and water resources availability of the Ebro river basin. Pyrenean headwaters cover only a 12% of the surface of the Ebro valley, but they generate 46.2% of the total runoff. However, the evolution of climate and land cover during the last decades disturbed the water balance of the region leading to important decreases in runoff generation (Beguería et al. 2003). Land cover changes during the 20th century are mainly characterised by a farmland abandonment in the hill slopes, and the increasing competence for the space in the valley bottom due to reservoir construction, tourism facilities and the need of meadows to feed the livestock in winter. Farmland abandonment that on average affected to 22% of the territory resulted in a expansion of dense shrubs and forests (nowadays the 64% of the surface of abandoned farmlands are forests in different stages of development and a 28% are covered by shrub).
Climate and land use scenarios suggest the continuity and even an acceleration of the adverse conditions for runoff generation. Thus, the role of the Pyrenees as repository of water to the lowlands is becoming seriously threatened for the 21st century.
This ST will contribute to the project with the following research activities:
- To analyse the effect of land cover and climate variability on the hydrology of the Pyrenees. For this purpose hydrological information from experimental plots, four monitored experimental basins with different vegetal cover, a dense network of gauging stations, and a recently obtained dense network of homogeneous and long-term climatic records (20th century) are already available. Information from experimental plots and experimental basins will allow to isolate the effect of land use and vegetation change on water quality and quantity (sediment transport, total runoff, response to rainfall events, depletion curves, etc.). All the sites are very close in distance, with practically equal climatic conditions and geological substrate. For this reason, differences in the hydrological behaviour of the different locations are linked to the contrasted land cover of each site, which reflects different conditions from the traditional agriculture and abandoned farmlands to dense forest. On the other hand the availability of long and homogeneous climatic and hydrologic series will permit to detect changes in runoff coefficients at basin scale. From such changes, it will be possible to infer valuable information about the role of the significant alterations that have occurred in land use and vegetation cover (deforestation/aforestation) on the hydrology of Pyrenean headwaters.
- Hydrological modelling (SWAT model and modelling tools developed by T 3.2) of the Upper Aragón river basin (2,181 km2). The study case is appropriate for the goal of the project since it has been subjected to large land use changes, is highly dependent on snow melting discharges, and it drains to the Yesa reservoir which supply water to new irrigated areas (actually: 60,700ha, projected: 88,000 ha) and will provide water to Zaragoza city (700,000 inhabitants). Models will be run for different land-use and climatic (downscaled RCMs as developed in ST 3.1.2 and from the PRUDENCE dataset) scenarios in order to assess the impact of environmental change on water availability and management in the region (simulation of different levels of aforestation in the 22% of the area composed by abandoned farmlands, simulation of the effect of the replacement of introduced species, mainly Pinus sylvestris, by native vegetation, such as Quercus pirenaica, and simulation of an rising timberline as consequence of the reduction of grazing activities and climate warming).
The proposed WP fits closely within the scope of the project. It tackles the analysis of the environmental change impact on the hydrology of a vulnerable mountainous region where water is a main issue for the economical development of the lowlands of NE Spain, a large and highly populated region. The experience of the Pyrenees will increase the geographical frame of the Project which enables a better understanding of the impact of climate change on mountainous areas. Moreover, analysis carried by ST 4.2.2 will add to the Project valuable information about the interaction between climate and plant cover changes on water resources availability. The latter is widely recognised as a very important factor for the hydrology at a basin scale, but very often it is marginally considered in comparison with climatic forcings. At the same time, this WP will be benefited with the availability of new modelling tools developed within the Project and the experience supplied by the other participants.
Subtask 4.2.3: Agriculture
Agroscope ART, Zurich, Switzerland [J. Fuhrer]
Agriculture in mountain regions produces different commodities and provides additional non-monetary services that are fundamental to support the local population (Bätzing, 1996) and to protect natural resources such as biodiversity (Cernusca et al., 1999). These services rely largely on financial inputs from other sectors, mainly from tourism, and/or government subsidies. With decreasing support and stronger market pressures due less protectionism, high production costs become critical and thus agriculture in many mountain regions is increasingly vulnerable to environmental constraints. The aim of this subtask is to evaluate direct and indirect consequences of climatic change in combination with shifting pressures from the political, social and economic environment.
Agriculture is a crucial sector for mountain economies, and any mountain policy explicitly addresses agricultural issues. The recommendations elaborated for actions in agriculture related to climate change and, in particular, to water in the selected test regions will be generalized to be applicable to other mountain regions of Europe. They will then be placed in the context of the current European Common Agricultural Policy (CAP), and of national and regional sectorial policies for the respective regions. The aim is to identify key policy aspects needed in the future to support agricultural structures in a multifunctional mountain landscape under changed climatic and hydrologic conditions.
The following issues will be addressed in the present subtask:
- Drought sensitivity will be assessed by statistical analysis of historical hydrological data for the selected catchments in relation to records of land cover, land use and agricultural activities; archived data and outputs from hydrological models (T 3.2) driven with historical data (T 2.2) will be used; drought sensitivity and critical conditions will be derived from the resulting relationships between climatic and agricultural indices..
- Drought risks for different combinations of land use and soil types will be evaluated on the basis of probability distributions of indices derived under pt. 1 for selected catchments using current and projected future climatic conditions from downscaled RCM outputs (ST 3.1.2) and soil moisture scenarios from T 3.2. and ST 3.3.4.
- Phenology-dependent water demands for different agricultural commodities will be calculated based on a per unit yield or available energy for crop and forage production and animal consumption using models for crops (CropSyst, Stoeckle et al. 2003; Torriani et al. 2007) and pastures (PaSim, Riedo et al. 1998) driven with downscaled outputs from RCM runs (ST 3.1.2) and projections of soil moisture from distributed hydrological models (T 3.2 and ST 3.3.4); current and future conditions will be compared and region-specific recommendations for improved water storage and use, soil water retention and soil protection to mitigate climate change impacts will be elaborated.
Subtask 4.2.4. Impacts on mountain forests
Forest Ecology, ETH-Zurich, Switzerland [A. Wolf, H. Bugmann]
This subtask does not intend to model the drivers of land use changes, but rather to assess the relative importance of LUCC compared to changes in climate with respect to forest structure and composition and for the carbon and water budgets of selected catchments. Accordingly, we will investigate the impacts of a changing water supply on forest ecosystems in European mountain areas. To this purpose, we will use a modified version of the biogeochemical ecosystem model LPJ-GUESS (Smith et al. 2001) to predict changes in forest structure, composition and on the fluxes of water and carbon as a consequence of changing climatic conditions and hence of water supply. The model has been successfully applied for a variety of studies, both in Europe and worldwide and can therefore be easily adapted for any mountain region in Europe. Furthermore, we will apply LandClim (Schumacher and Bugmann, 2006), a model specifically developed to assess the relative importance of climatic effects (drought), wildfires and management, including changes in forest cover, for future forest landscape dynamics. LandClim has been applied for forests in the European Alps as well as in the Rocky Mountains; in an ongoing, parallel project, its applicability is expanded to Mediterranean forests. Hence we expect that also this model will have a wide range of applicability in the context of the ACQWA project. To drive the models, we will use climate scenarios from ST 3.1.1and 3.1.2 and – concerning soil moisture – from T 3.2 and ST 3.3.4. To assess the importance of land use and land cover changes, including afforestation/deforestation, scenarios based on the EU FP6 project “ALARM” and the FP5 project “ATEAM”, in which this group has been involved in the past, will be used. We will supply information on forest productivity, fire probabilities and associated losses in forest productivity.
We will focus on the following key issues:
- sensitivities and critical conditions (i.e., quantitative sensitivity indicator for drought) for forest ecosystems, namely:
- How drought conditions increase mortality of forest tree species
- How drought conditions influenced productivity and forest structure.
- In addition, Subtask 4.2.4 will assess future climatic change (mainly droughts, i.e. focus on extreme events rather than averages) and its influence on forest structure and composition under different scenarios of climate (ST 3.1.1) and land use. How does this influence the capacity of forests with respect to protection and productivity (feedback to WP2)?
- How do changes in climate (mainly water supply) interact with changes in fire frequency and management changes (link to EU FP6 project “ALARM”)?
- Predict changes in availability of economically important forest products in mountain regions as basis for T 4.3.
- What are the consequences of afforestation/deforestation for the water budget of catchments (link to Swiss NCCR Climate project EcoHydro) focusing on
- Consideration of different time scales and consequently spatial scales (e.g. short-time, local climate, longer time catchment water balance)
- Effects of different management regimes.
In this respect, recent work done by the consortium members has shown the potential of distributed modelling for estimating the effects of land use changes and forest damage due to wind storms and general deforestation due to hypothetical climate change scnearios on peak flows magnitude and timing, as well as on hillslope erosion patterns and basin sediment yield (Rosso and Burlando, 1999; Kuntner and Burlando, 2003; Burlando and Kirsch, 2005; Molnar et al., 2006; Kirsch et al, 2007). Accordingly, the hydrological models implemented to address Task 3.2, which will be interfaced with the biosphere model of Subtask 3.3.5, will be the basis for the analysis of the impact of CC induced afforestation and deforestation scenarios as predicted by the EU-FP6 “ALARM” and EU-FP5 “ATEAM” projects.
Subtask 4.2.5: Tourism
HEID, Geneva, Switzerland [E. Wiegandt]; MonterosaStar Srl, Macugnaga (Verbania), Italy [Luigi Corsi]
Tourism in mountain regions constitutes a major economic sector in developed countries with large areas of high altitude territory and is a potential source of growth for mountainous developing regions (ex. Central Asia and South America). The greatest direct climate impacts for mountain tourism are expected be on winter tourism and these effects will vary primarily according to altitude. Given temperature and precipitation predictions, Switzerland appears the relatively insensitive to changes in snow cover, given the number of high altitude resorts (OECD 2007). Regional differences are nevertheless significant and will produce "winners and losers" not only in Switzerland but throughout Europe and beyond. Moreover, other consequences of climate change such as changing natural hazards will affect tourism. Given that tourism often results in more extensive and intensive use of territory, more intense and/or more frequent catastrophic events could have significant negative consequences. Furthermore, climate impacts must be evaluated in terms of their interaction with socio-economic factors influencing tourist behaviour. The goal is to develop a methodology to examine the interactions between climate and social factors as they affect mountain tourism. This project will validate a general analysis of impacts on tourism using mostly regional Alpine (Swiss) data because these are plentiful and reliable. The framework can then be applied to other regions to highlight the relative importance of different key components, thereby identifying particular vulnerabilities and potential policy and institutional mechanisms to address emerging problems. Focus will be on key issues:
- Identification of Alpine regions of the Rhône Valley able to maintain winter tourism activities under predicted temperature and precipitation conditions and those which will no longer be viable with current infrastructure (Abegg, 1996, provides a starting point for these investigations). Sample question of general relevance for all regions: is a particular season-length based on minimal snow cover a critical consideration?
- Identification of future water demands of the tourism sector based on projections derived from (1), including estimations of water use related to personal tourist consumption plus projections of artificial snow use derived from climate predictions. Parallel evaluation of demands predicted from other sectors, including household use (permanent residents), hydroelectricity, and agriculture (from ST 4.2.3) and using model results from T 2.4 to obtain overall water demand.
- Analysis of potential shortages/deficits based on the above and results of hydrological models predicting supply, generated by T 3.2.
- Identification of new vulnerabilities due to natural hazards, incorporating results from T 3.4.3.
- Specification of criteria influencing tourist choice of venue in order to evaluate relative importance of snow versus other characteristics for choice of vacation location. Data will be obtained through analysis of historic/current tourism patterns, complimented by interviews.
- Comparative assessment of water demand and economic return of key economic sectors in mountain regions in order to undertake comparative cost/benefit analysis of adaptation strategies to guarantee adequate water supply to maintain tourism relative to measures to foster hydroelectricity production or preserve mountain agriculture. Results from the Swiss case will identify key factors to maintain viable mountain tourism which can be used as guides for policy makers seeking to provide incentives or elaborate criteria for tourist development projects.
Task 4.3: Policy response and adaptation
Graduate Institute of International Studies (HEID), Geneva, Switzerland [U. Luterbacher, E. Wiegandt]; Columbia University Consortium for Risk Management [G. Chichilnisky and P. Eisenberger]; Instituto Torcuato di Tella, Buenos Aires , Argentina [T. di Tella, S. Orsini, D. Perczyk]; Institute of Water Problems and Hydropower, Kyrgyz National Academy of Sciences, Bishkek Kyrgyzstan [D. Mamatkanov, O., G. Shalpykova and other co-workers]
UNESCO Centre for Water Law, Policy and Science, Univ. of Dundee [A.Rieuclarke, A. Allan]
Climate change will likely modify seasonal and overall water availability and, as a result, there will be increased competition for water. This Work Package has two interrelated goals:
- Overall assessment of changes in water availability based on integrated results of WP 2.4 (integrated modelling of socio-economic drivers) and focused impact studies (ST 4.1-4.2.4) and of hydrological studies (T 3.2) through an evaluation of the respective vulnerabilities of sectors within the system
- Presentation of different policy options and analysis of their respective costs and benefits to individual sectors and to the society as a whole, applied to different regions. Developed, stable systems (Alps) will be compared to developing and institutionally more fragile areas (Central Asia, Andes). To design effective policies the inputs from the natural science analyses are important nevertheless risks of unexpected or catastrophic events cannot be eliminated. Policies for the design of institutions that enhance collective well being will help lessen the negative impacts of climate change and resulting disturbances of the hydrological cycle.
- Costs to sectors and to society are defined in terms of specific discount rate assumptions and the 1% of GDP mitigation benchmark figure adopted, for example in the Stern Review in 2006 and which still be modified upon by the Columbia group; discount rate problems discussed in Chichilnisky (1997) and Chichilinisky and Heal (1993, 1996) which have shown that different kinds of discount rates should be assessed for collective gods such as the environment as opposed to private goods Research conducted by Chichilnisky, and the Columbia group will permit evaluation of whether the costs minus benefits of climate change under specific discount rate analysis exceed the 1% of GDP of the regions (or a revised figure), or not. If net costs are larger than 1% of GDP of the region, it is worth undertaking mitigation under standard cost benefit conditions. These are fundamental political decisions and will affect how water would be distributed among sectors as well as other policy measures to be explored through scenarios. The following considerations underlie scenario construction and will permit comparative policy analysis:
- In the European Alpine region, well-defined institutional structures supported by stable states have regulatory frameworks to assure water distribution among sectors and groups. Climate change and parallel socio-economic changes will test the resiliency of these policies and may increase tensions among groups in the European Alps but it is expected that the robust institutional structure has a high potential for adaptation. In the case of Central Asia, a relatively undeveloped region with an unstable political system, water allocation is currently a problem that will only be aggravated by climate change. Our analysis will identify factors that may facilitate adaptation, given the Alpine experience, and evaluate their applicability to the more fragile institutional situation of Central Asia and the Andes, where the situation is more solid than in Central Asia but where important social and political instabilities are still present within important countries such as Chile (Aconcagua basin) and Argentina (Cuyo basin). In these two latter cases, strong competition for water use between agricultural, industrial hydropower and household sectors might develop with climate change.
- The European Alps are near capacity in mobilizing water for energy use but this is not the case in Central Asia and the Andes, which have great unused potential in the use of water resources for electric power. Preliminary analyses of the Kyrgyz region have shown that these unused potentials can ultimately benefit the whole of Central Asia and contribute to a reduction of greenhouse gas emissions. The same might be possible in the Andes.
- Having assessed the policy choices; we then look at the legal environment in which such policies are implemented. This would involve an analysis of the applicable law relating to integrated water resources management. In Europe this would include an analysis of the EU Water Framework Directive, the 92 UN ECE Helsinki Convention, as well as various national and provincial/ local legislation. The aim would be to identify the key legal elements that enhance a state’s/ region’s ability to adapt to climate change. The work in Central Asia would therefore be to assess whether these legal elements exist, and where there are gaps, the options for legal reform.
The elaboration of the integrated assessment model and the design of scenarios based on above assumptions will provide the following deliverables:
- An integrated model linking regulations for water allocation to its actual distribution among sectors. It will include not only climate factors as but also the influence of market forces and political conditions, giving a comprehensive picture of water availability.
- 1The basic model design is based upon sub-models of rural and industrial sectors present together in different but adjacent regions. The two regions interact but they are formulated separately to permit identification of the different effects of environmental changes in each area. Both are described by a general structure that includes four main sectors: (a) Population, (b) Economy and Resources, including trade, a financial system, and industry (c) Cultural organization, and (d) Government.
- Scenarios to explore particular vulnerabilities of high mountain areas and competitive aspects of water use among different sectors and regions. The impact of specific incentive structures modifying land use patterns will be modeled and analyzed. This includes the study of the impact of different revenue streams arising from different uses of the available land: eg if much more revenue can be generated from tourism more agricultural and herding land will be use for it, the same reasoning can be applied to other economic sectors. Gaps in water supply resulting from competing sectors will be identified, e.g. for agriculture it will be possible to define the amount needed in each month of the year (from ST 4.2.3), The same will be done with tourism and hydropower, permitting calculations of total water demands and comparison with availability. This supposes again coordination with ST 4.2.3 (agriculture) and ST 4.2.1 (Economic aspects of hydropower). This provides likelihoods for the size and timing of water gaps.
- Analyses of the effects and economic cost under specific discount rate assumptions of the consequences of climate change on present water use patterns for the different types of economic activities enumerated under T 4.2.
- Evaluation the costs and benefits of water allocation schemes for different sectors and different regions enumerated under T 4.2
- Scenarios exploring different policy options at local and regional levels (taking into account trans-boundary water agreements) to reduce water deficits within sectors and to equitably and efficiently distribute water among users and sectors.
- Comparisons between European and non-European mountain regions (Central Asia, Argentine and Chilean Andes) to determine whether or not production technologies, consumption patterns, and regulatory frameworks developed in Europe i.e., a methodology to compare European and non-European mountainous region’s legal frameworks in terms of adaptability to climate change. We will determine if the acceptable level of equity and efficiency achieved in Europe can be successfully adapted elsewhere.
Evaluations of conditions necessary to tap potential from unused hydropower and of the extent to which such developments could contribute to meeting greenhouse gas mitigation goals and fit into the CDM Kyoto system as well as to lowering regional tensions, or, conversely, what factors might aggravate them. Again coordination with ST 4.2.1 is indispensable here. This latter aspect will lead to policy recommendations for how various asymmetries between regions might be corrected while also contributing to mitigating greenhouse gas emissions.