Emulating spatially resolved annual maximum temperatures of Earth system models using MESMER-X

Emulators of Earth System Models (ESMs) are complementary to ESMs, in that they provide climate information with reduced computational costs. However, climate extremes, one of the most impactful consequences of climate change, remain challenging to emulate in all of their aspects. Here, we propose a method for the emulation of local annual maximum temperatures, with a focus on reproducing essential statistical properties and correlation in space and time. The Modular Earth System Model Emulator for Regional eXtremes (MESMER-X) is based on sampling from the generalized extreme value distribution and we show quantitatively that the resulting emulations of annual maximum temperature can reproduce the temporal evolution and spatial patterns of the underlying ESM simulations. Given the general design of the emulator and the good performances for annual maximum temperatures, the proposed methodology can be applied to other indicators of climate extremes, illustrated here with an indicator of fire weather.