Abstract. Flash droughts tend to be disproportionately destructive because theyintensify rapidly and are difficult to prepare for. We demonstrate that the2017 US Northern Great Plains (NGP) flash drought was preceded by abreakdown of land–atmosphere coupling. Severe drought conditions in the NGPwere first identified by drought monitors in late May 2017 and rapidlyprogressed to exceptional drought in July. The likelihood of convectiveprecipitation in May 2017 in northeastern Montana, however, resembled that ofa typical August when rain is unlikely. Based on the lower tropospherichumidity index (HIlow), convective rain was suppressed by theatmosphere on nearly 50% of days during March in NE Montana and centralNorth Dakota, compared to 30% during a normal year. Micrometeorologicalvariables, including potential evapotranspiration (ETp), were neither anomalouslyhigh nor low before the onset of drought. Incorporating convective likelihoodto drought forecasts would have noted that convective precipitation in theNGP was anomalously unlikely during the early growing season of 2017. It maytherefore be useful to do so in regions that rely on convectiveprecipitation.
Lessons Learned from the 2017 Flash Drought across the U.S. Northern Great Plains and Canadian Prairies
Abstract The 2017 flash drought arrived without early warning and devastated the U.S. northern Great Plains region comprising Montana, North Dakota, and South Dakota and the adjacent Canadian Prairies. The drought led to agricultural production losses exceeding $2.6 billion in the United States, widespread wildfires, poor air quality, damaged ecosystems, and degraded mental health. These effects motivated a multiagency collaboration among academic, tribal, state, and federal partners to evaluate drought early warning systems, coordination efforts, communication, and management practices with the goal of improving resilience and response to future droughts. This essay provides an overview on the causes, predictability, and historical context of the drought, the impacts of the drought, opportunities for drought early warning, and an inventory of lessons learned. Key lessons learned include the following: 1) building partnerships during nondrought periods helps ensure that proper relationships are in place for a coordinated and effective drought response; 2) drought information providers must improve their understanding of the annual decision cycles of all relevant sectors, including, and beyond, direct impacts in agricultural sectors; and 3) ongoing monitoring of environmental conditions is vital to drought early warning, given that seasonal forecasts lack skill over the northern Great Plains.
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- Award ID(s):
- 1633831
- NSF-PAR ID:
- 10279141
- Date Published:
- Journal Name:
- Bulletin of the American Meteorological Society
- Volume:
- 101
- Issue:
- 12
- ISSN:
- 0003-0007
- Page Range / eLocation ID:
- E2171 to E2185
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1175/BAMS-D-19-0272.1
