Cluster of Excellence Climate, Climatic Change, and Society (CLICCS)

The program aims to understand climatic changes by taking into account internal variability, extreme events, and unexpected side effects.  It spans a wide thematic range: from basic research on climate system dynamics and social dynamics to transdisciplinary investigation of human-environment interactions. The overarching research question is: Which climate futures are possible and which are plausible?

The 2015 Paris Agreement provides a powerful impetus not only for climate policy but also for climate research. The research challenges resulting can only be tackled in a program spanning the range from basic research on climate and social dynamics to the transdisciplinary exploration of human-environment interactions—exactly the CLICCS vision.

Knowledge for decision makers

CLICCS has extensive experience in interdisciplinary climate research and will identify plausible climate futures at all scales - from global to local. This expertise is key to providing the information decision makers need to plan for a sustainable future - including the ability to cope with surprises in the climate system. The results on possible and plausible climate futures are summarized annually in the "Hamburg Climate Futures Outlook". This knowledge is made available worldwide.

Which climate futures are possible – and which are plausible?

CLICCS will examine how the climate is changing, and thus how society is changing - and how this, in turn, affects the climate. It will identify all climate futures that are consistent with both the climate system and social dynamics (possible scenarios) - and those that are more likely to actually occur (plausible scenarios). At present, it is not plausible to meet the 1.5 degree target. This was revealed by the analysis of ten key societal factors that are crucial for deep decarbonization.

In Order to understand the controlling processes, measurement data and computational models of natural systems, coupled human/environmental systems, and social systems are used and further developed. In this way, targeted adaptation and mitigation strategies can be formulated. Therefore three research areas are intertwined:

A - provides the basis for understanding the dynamics of the climate system. This includes climate variability as well as the extremes of climate change expected in the future and already taking place.

B - examines the climate-driven dynamics of social systems. It provides the social science basis for plausible climate scenarios focused on a permanent shift away from fossil fuels (deep decarbonization).

C - analyzes coupled human-environment dynamics at the regional level. Here, climate change becomes visible and sustainable adaptation can be realized by local actors.

The three areas (CLICCS Themes) combine research from 14 specialized projects. The research is supported by High-Performance Computing and Data-Intensive Science.