Session D4: Urban environment and regional climate change


Tomas Halenka , Gaby Langendijk, Bert Van Schaeybroeck, Peter Hoffmann  and Michal Belda

Session Summary

The aim of the session is to gather members of CORDEX community interested in a common approach to include urban effects in the CORDEX simulations and framework, communicating the knowledge and expertise achieved in the studies of urban effects in high resolution regional climate simulations, and proposing a way forward, which within CORDEX activities might be an FPS on urbanization, considering big cities (megacities) across interested CORDEX domains. A limited number of well focused contributions will be accepted as orals to start the discussion. There are also limited options to display posters, and you are welcome to express the interest via submission.


Thomas Halenka

Session description

The cities play a fundamental role in local to regional scales through modification of heat and moisture fluxes, as well as affecting many other processes. Urban areas - as a specific type of land-use - require special parameterization of local processes to get their effects properly included. Moreover, both the number of big cities and their populations are increasing. Thus, the climate change impacts on the population will become increasingly pressing through urban environments. This is especially critical in connection to extreme events, for instance heat waves with extremely high night time temperatures exacerbated by the urban heat island effect with significant consequences for human health. Additionally, with increasing model resolution, the proper parameterization of urban processes is playing an important role in understanding local and regional climate change, as an increasing part of model gridboxes is filled with the urban land-use. To get the urban effects properly described it is vital to provide correct assessment of climate change impacts in the cities and further effects on different adaptation and/or mitigation options proposed by urban decision-makers. Therefore, as cities are becoming one of the most vulnerable environments under climate change, increasing effort dedicated to these aspects is becoming highly relevant to the CORDEX community. Specifically, the event of CORDEX 2019 hosted by a megacity like Beijing, is an appropriate place to organize such a session on urbanization and to enhance this discussion within the wider CORDEX community in a more coordinated fashion.

The purpose of the special session on urbanization is to gather members of the CORDEX community interested in discussing and exploring a common approach to include the urban effects within the CORDEX simulations and framework, to gather and communicate the knowledge and expertise already achieved in the studies of urban effects in high resolution regional climate simulations, to discuss the urban effects, and last, but not least, to propose a way forward. A clear option, consistent with CORDEX structure, is to develop an FPS on urbanization, which might go across the CORDEX domains considering selected big cities (even megacities) in interested CORDEX domains.

A limited number of well-focused contributions will be accepted as oral presentations to start the discussion. There could also be a limited number of posters, you may express the interest in this topic via the submission. The format of the workshop session will follow a mixed approach of presentations and interactive round-table discussion. A few key questions are proposed for discussion: the main scientific challenges to incorporate urban issues; a starting point for better understanding the urban phenomena in currently available simulations (CORDEX-CORE, EURO-CORDEX, CP models); ways forward to incorporate urban effects into CORDEX simulations; impact studies and user-specific relevance of urban climate change projections and information (among others).