Heat and Evaporation Causing 'Irreversible' Drying of Mongolia
Heat and Evaporation Causing 'Irreversible' Drying of Mongolia

UNIVERSITY OF GOTHENBURG, SWEDEN — Mongolia's semi-arid plateau may soon become as barren as parts of the American Southwest due to a "vicious cycle" of heatwaves, which exacerbates soil drying, and ultimately produces more heatwaves — according to a group of climate scientists.

Writing in the journal Science, the researchers warn that heatwaves and concurrent droughts have increased significantly during the past two decades, with troubling implications for the future.

Using tree-ring data, which offer a glimpse of regional climates from before modern weather logs, the researchers developed heatwave and soil moisture records that suggest recent consecutive years of record high temperatures and droughts have been unprecedented in more than 250 years.

According to the study's findings, the record high temperatures in the region are accelerated by soil drying, and together these changes are magnifying the decline of soil water.

When soil is wet, evaporation cools air at the surface.

However, when soil no longer has any moisture, heat transfers directly to the air.

The result is more heatwaves, which means more soil water losses, which means more heatwaves.