Journal article
Exceptional heat and atmospheric dryness amplified losses of primary production during the 2020 U.S. Southwest hot drought
Global change biology, Vol.28(16), pp.4794-4806
04/22/2022
DOI: 10.1111/gcb.16214
PMCID: PMC9545136
PMID: 35452156
Appears in UI Libraries Support Open Access
Abstract
Earth's ecosystems are increasingly threatened by "hot drought," which occurs when hot air temperatures coincide with precipitation deficits, intensifying the hydrological, physiological, and ecological effects of drought by enhancing evaporative losses of soil moisture and increasing plant stress due to higher vapor pressure deficit (VPD). Drought-induced reductions in gross primary production (GPP) exert a major influence on the terrestrial carbon sink, but the extent to which hotter and atmospherically drier conditions will amplify the effects of precipitation deficits on Earth's carbon cycle remains largely unknown. During summer and autumn 2020, the U.S. Southwest experienced one of the most intense hot droughts on record, with record-low precipitation and record-high air temperature and VPD across the region. Here, we use this natural experiment to evaluate the effects of hot drought on GPP and further decompose those negative GPP anomalies into their constituent meteorological and hydrological drivers. We found a 122 Tg C (>25%) reduction in GPP below the 2015-2019 mean, by far the lowest regional GPP over the Soil Moisture Active Passive satellite record. Roughly half of the estimated GPP loss was attributable to low soil moisture (likely a combination of record-low precipitation and warming-enhanced evaporative depletion), but record-breaking VPD amplified the reduction of GPP, contributing roughly 40% of the GPP anomaly. Both air temperature and VPD are very likely to continue increasing over the next century, likely leading to more frequent and intense hot droughts and substantially enhancing drought-induced GPP reductions.
Details
- Title: Subtitle
- Exceptional heat and atmospheric dryness amplified losses of primary production during the 2020 U.S. Southwest hot drought
- Creators
- Matthew P Dannenberg - University of IowaDong Yan - University of ArizonaMallory L Barnes - Indiana UniversityWilliam K Smith - University of ArizonaMiriam R Johnston - University of IowaRussell L Scott - Southwest Watershed Research CenterJoel A Biederman - Southwest Watershed Research CenterJohn F Knowles - California State University, ChicoXian Wang - University of ArizonaTomer Duman - University of New MexicoMarcy E Litvak - University of New MexicoJohn S Kimball - University of MontanaA Park Williams - University of California, Los AngelesYao Zhang - Peking University
- Resource Type
- Journal article
- Publication Details
- Global change biology, Vol.28(16), pp.4794-4806
- DOI
- 10.1111/gcb.16214
- PMID
- 35452156
- PMCID
- PMC9545136
- NLM abbreviation
- Glob Chang Biol
- eISSN
- 1365-2486
- Publisher
- Wiley
- Grant note
- DOI: 10.13039/100000104, name: National Aeronautics and Space Administration, award: 80NSSC19K1335, 80NSSC20K1805; DOI: 10.13039/501100008982, name: National Science Foundation of Sri Lanka, award: 2131853; DOI: 10.13039/100013316, name: Strategic Environmental Research and Development Program, award: RC18‐1322; DOI: 10.13039/100000199, name: U.S. Department of Agriculture, award: 58‐0111‐17‐013, 58‐3050‐9‐013; DOI: 10.13039/100008893, name: University of Iowa
- Language
- English
- Date published
- 04/22/2022
- Academic Unit
- Geographical and Sustainability Sciences
- Record Identifier
- 9984259387402771
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