Numerical simulation of thermal effects of urban green enhancements in different urban environments in the city of Augsburg (Bavaria, SE Germany)

The interdisciplinary research project Abc (Augsburg bleibt cool – Augsburg stays cool) – funded by the German Federal Ministry for Environment, Nature Conservation and Nuclear Safety – deals with different aspects of heat-stress exposure and adaptation to heat-stress in indoor and outdoor urban environments in the urban area of Augsburg (Bavaria, SE Germany).

As one essential research approach this includes the estimation of the thermal effects of vegetation enhancements in different urban environments via numerical simulations performed with the ENVI-met V4 numerical model.

For several model domains – each of them covering 300 m x 300 m with a 2 m x 2 m horizontal resolution - model runs have been performed utilizing observational data for a heat wave end of July 2019 as meteorological forcing, thus serving as a climate analogue for thermal conditions expected to appear more frequently under future climate change conditions. For each domain model runs for the current-state and several adaptation scenarios have been performed. Adaptation scenarios thereby comprise varying measures for enhancing urban green (street and facade greening) and blue infrastructure.

In this contribution we present and discuss selected model settings and scenarios.

Model results indicate the general capability of vegetation enhancements to counteract heat-stress exposure in urban environments. However, partly also contrary effects emerge pointing to the complex interdependencies within the urban climate system which have to be taken into account when projecting urban heat island adaptation strategies.