Impact of drought on daytime surface temperature in semi-arid biomes across the New Mexico Elevation Gradient
Abstract
In the last two decades, extreme drought events correlated with low precipitation and higher temperatures have become more frequent, and are expected to increase, especially in semi-arid ecosystems, such as in the Southwestern United States. Droughts can impact the local energy balance through changes in environmental conditions and the eco-physiological functioning of these systems. We studied how droughts affect surface temperature through the partitioning of the energy balance equation in several biomes in the New Mexico Elevation Gradient flux tower network, ranging from grasslands to a subalpine mixed-conifer forest. We separated the records for each site into drought and non-drought years, based on soil water content and vapor pressure deficit data. We then used the energy balance equation to quantify changes in surface temperature, and explain what caused these changes. By comparing the sites, we assessed the biome-specific sensitivity of surface temperature to drought. While some sites show similar changes in surface temperature during drought, we did find significant biome-specific differences in the energy balance terms. Our results highlight differences in the ability of each ecosystem across the elevation gradient to mediate the effects of increasing air temperatures and decrease in soil water availability through aerodynamic and evaporative cooling, depending on the vegetation cover in each site. A better understanding of these relationships will enhance our ability to predict the impact of future droughts on surface temperature.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.B31I2499D
- Keywords:
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- 0410 Biodiversity;
- BIOGEOSCIENCES;
- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCES;
- 0428 Carbon cycling;
- BIOGEOSCIENCES;
- 1616 Climate variability;
- GLOBAL CHANGE