This session is a forum for both climate and climate impacts researchers to discuss recent advances and challenges in climate impacts assessments and in the associated, multi-scale and multi-disciplinary modelling techniques. In its widest sense, the linking between climate and impact models ranges from the simple application of climate indicators, to more sophisticated top-down approaches (e.g. statistical downscaling techniques), to bottom-up techniques like response surfaces, and - ultimately - to an explicit online coupling of both model types. Despite this variety of methods and applications, providers and users frequently face a number of common methodological challenges and contextual demands.
Therefore, the first part of this session focusses on recurrent challenges in the linkage between impact and climate models such as the selection of a suitable methodological framework, data sets, models, downscaling techniques or tools, the influence of this selection on the simulation result, the uncertainty quantification and attribution, approaches to preserve extremes and physical consistency, or
approaches to deal with probabilistic projections.
The second part will move towards applications in climate impact assessments. As the Intergovernmental Panel on Climate Change (IPCC) is preparing a special report on the impacts of 1.5°C of global warming, the impacts, vulnerability, and adaptation community is more pressed than ever to provide reliable quantitative estimates of the costs and damages expected at different levels of global warming. Although advanced models are available to simulate the response of agriculture, natural ecosystems, hydrology, human health, and other parts of the human environment and economy to global climate change, integrating the impacts across these different sectors remains a key challenge, not least because different processes may interact. Moreover, climate impact projections can diverge substantially between different impact models, reflecting uncertainty in model structure and parameters.
Particular areas of interest in this part of the session are the use of multi-model ensembles for estimating confidence levels and identifying model differences; the evaluation of models using observational data; the application of statistical methods in order to better differentiate projected impacts between different global warming levels; and the application of impact models to relevant climate scenarios beyond the most common set of RCPs, e.g. long-term stabilization, low warming, or overshoot scenarios. Contributions based on multi-model comparison projects such as the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) or the Agricultural Model Improvement and Intercomparison Project (AgMIP) are encouraged.
The session invites all contributions that address one or more of the raised challenges. We especially welcome contributions from different impact disciplines (e.g. hydrology, agriculture, and cryosphere among others), climate model data providers, climate service centres, and international projects working on the interface between climate and impact models. The overall aim of the session is to foster the scientific exchange between the different communities and to promote a joint effort to improve impact assessment techniques.