IMPACT2C

Political discussions on the European goal to limit global warming to 2°C above pre-industrial levels demands that discussions are informed by the best available science on projected impacts. Moreover, a key concern for policymakers is the difference, and possible benefits, from keeping warming to below 2 degrees. This information can serve as a major motivation in global negotiations and actions, in relation to carbon emissions. In this context, IMPACT2C pursued a multi-climate and multi-impact model approach which would deliver robust information in relation to climate change and impacts in Europe, and key non-European vulnerability hotspots, in +1.5, +2, and +3 degree Celsius worlds.

The overall objectives of IMPACT2C were:

• To quantify projected changes in climate in Europe and key non-European vulnerable regions under a +2 °C world, using a range of different global and regional climate models;
• To quantify projected impacts in a number of different economic sectors under a +2 °C  world;
• To quantify projected impacts in a +2 °C world from a cross-sectoral perspective, e.g. for particularly vulnerable areas that are subject to multiple impacts where cumulative effects may arise (e.g. in the Mediterranean region) and in relation to cross-cutting themes (e.g. cities and the built environment).

IMPACT2C utilised a range of models within a multi-disciplinary international expert team and assessed impacts in a number of different economic sectors including, water, energy, infrastructure, coasts, tourism, forestry, agriculture, ecosystems services, and health and air quality-climate interactions.

IMPACT2C introduced key innovations, namely:

• Harmonised socio-economic scenarios to ensure that both individual and cross-sector assessments were aligned to the 2°C (and 1.5°C and 3°C) scenarios for both impacts and adaptation, e.g. in relation to land-use pressures between agriculture and forestry.
• A core theme of uncertainty, and pursued a methodological framework which integrated the uncertainties within and across the different sectors, in a consistent way. In doing so, analysis of adaptation responses under uncertainty was enhanced.
• A cross-sectoral perspective was adopted to complement the sector analyses. A number of case studies were undertaken for particularly vulnerable areas, subject to multiple impacts, with the focus being on cross-sectoral interactions, and cross-cutting themes (cities). The project also assessed climate change impacts in some of the world's most vulnerable regions: Bangladesh, Africa (Nile and Niger basins), and the Maldives. In addition, the project endeavoured to communicate the results of the project to policymakers by developing a number of policy briefs, which summarised key results and policy implications.

The results of the analyses undertaken in the IMPACT2C project are detailed in a user-friendly interactive IMPACT2C web-atlas. It shows the impacts of a 2°C global warming on various European sectors and some key vulnerable regions outside Europe.

Furthermore, the main results of the project are reflected within several policy briefs which comprise:

Policy-Brief#1: Analysis of early IMPACT2C climate modelling results. This policy brief provides a summary of the initial findings of the project, reporting key lessons from the climate modelling analysis.

Policy-brief #2: IMPACT2C modelling results: climate change and sea-level rise from a 2°C climate. This policy brief provides a summary of the detailed regional climate modelling results for Europe.

Policy-brief #3: IMPACT2C modelling results for a 2°C climate for key global vulnerable regions. This policy brief provides a summary of the findings on the impacts of 2°C on key vulnerability global hot-spots, focusing on the Maldives, Bangladesh and the Niger and Upper Blue Nile River Basins in Africa.

Some key results of the analyses undertaken in IMPACT2C for a future +2°C world include:

• In most regions of Europe, projected surface warming will exceed the global mean 2ºC global warming;
• Projections of annual mean precipitation change indicate wetter conditions in northern Europe and drier conditions in Southern Europe;
• A European-wide increase in the frequency of extreme events is expected;
• Heatwaves are projected to double while extreme precipitation events tend to become more intense;
• The spatial and sectoral distribution of impacts is complex within Europe with some areas and sectors potentially benefiting, while others may suffer negative impacts;
• For core summer tourism, areas of Central and Northern Europe may experience an increase in their attractiveness, whereas some areas of the Mediterranean chiefly Spain, Italy, and Greece, may experience warming which sends them over an optimal comfort level for tourism;
• For winter tourism demand, analysis shows that up to 10 million overnight stays are at risk, with Italy and Austria being most exposed to this impact;
• In the energy sector, changes in wind energy potential, and solar photovoltaic potential show little to no change in a +2°C world across most parts of Europe. Larger changes are projected for changes in gross hydropower potential, with areas in northern Europe increasing by up to 20%, while areas in Southern Europe may experience reductions of up to 20%;
• In the health sector, changes in ozone and particulate matter in a two degree world are shown to be small, with air pollution policy exerting a more important effect on changes in these pollutants;
• Heat mortality in Europe is expected to increase by an average of around 23,000 additional heat related deaths. Countries particularly exposed to these impacts are Greece, Spain, Cyprus, Bulgaria, Hungary, and Romania;
• In the agriculture sector, there is a projected overall loss in rain-fed crop calorie yield of around 1.6%, with robust negative impacts being concentrated in Western and Southern Europe;
• In the forestry sector, changes in productivity are projected to increase across Europe by between 10% and 20%;
• In the water sector, extreme flood magnitudes are projected to increase substantially in parts of Central and Southern Europe, whereas in Northern Europe changes in extreme flood magnitude are projected to decrease. Streamflow droughts on the other hand are projected to become more intense in Southern Europe, whereas in parts of Scandinavia and Eastern Europe streamflow drought may become less intense;
• In coastal areas, flooding associated with sea level rise are projected to be upwards of 50 million Euro per annum, in the UK, Netherlands, Belgium and France;
• Projections of changes in mean surface temperature for Western and Eastern Africa show that the projected warming is greater than the global mean of +2ºC;
• Projections of changes in annual precipitation over Western Africa indicate a modest increase, whereas over eastern Africa no clear trend is projected.