Hot extremes have become drier in the United States Southwest

Karen A. McKinnon (), Andrew Poppick and Isla R. Simpson
Additional contact information
Karen A. McKinnon: University of California
Andrew Poppick: Carleton College
Isla R. Simpson: National Center for Atmospheric Research

Nature Climate Change, 2021, vol. 11, issue 7, 598-604

Abstract: Abstract The impacts of summer heat extremes are mediated by humidity. Increases in temperatures due to human-caused climate change are generally expected to increase specific humidity; however, it remains unclear how humidity extremes may change, especially in climatologically dry (low-humidity) regions. Here we show that specific humidity on dry days during summer (defined here as July–September) has decreased over the past seven decades in the United States Southwest, and that the greatest decreases co-occur with the hottest temperatures. Hot, dry summers have anomalously low evapotranspiration that is linked to low summer soil moisture. The recent decrease in summer soil moisture is explained by declines in June soil moisture, whereas the interannual variability is controlled by summer precipitation. Future projections of hot, dry days in the Southwest are uncertain due to the large spread in the Coupled Model Intercomparison Project phase 6 (CMIP6) trends in soil moisture and precipitation through 2100.

Date: 2021
References: Add references at CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
https://www.nature.com/articles/s41558-021-01076-9 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcli:v:11:y:2021:i:7:d:10.1038_s41558-021-01076-9

Ordering information: This journal article can be ordered from
https://www.nature.com/nclimate/

DOI: 10.1038/s41558-021-01076-9

Access Statistics for this article

Nature Climate Change is currently edited by Bronwyn Wake

More articles in Nature Climate Change from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().