Understanding Drought: Information and Current Status

Mar 12, 2021

By Krista Ehlert

Drought and Climate Variability

Although drought is a part of normal climate variability across the U.S., it is of particular concern in the Northern Great Plains (NGP) and other areas in the West, where water is often a limiting factor. Specifically, in the NGP drought occurred 27% of the time during 1944-1984 (Holechek et al. 1989), with 20th century droughts being shorter in duration than the past Great Plains megadroughts (during 1000-1300; Cook et al. 2007). Despite droughts being shorter in duration, climate change is expected to increase drought frequency and severity in the NGP because of an increase in evaporative demand, a higher proportion of precipitation coming from high-intensity events, an increase in the number of dry days, and reduced snowpack (Hanberry et al. 2019). Adding to that are predictions of climate change expanding the summer season, with more extremely hot days, and a shrinking of the winter season with fewer extreme cold days (Hanberry et al. 2019). Taken together, these changing climate patterns have wide implications for rangeland and crop production - notably, a longer growing season, soil moisture deficits in the late growing season, and increased water stress between rains.

Current Drought Status

One way producers can manage drought impacts is to be proactive instead of reactive, both with staying up to date on the current drought status and making management decisions. The University of Nebraska-Lincoln (UNL) hosts the United States Drought Monitor, which is available for South Dakota on the U.S. Drought Monitor website. It is updated every Thursday. The latest map from February 4 has 72% of the state in the D1 - Moderate Drought intensity, 14% in D2 - Severe Drought intensity, and nearly 2% in D3 - Extreme Drought intensity. In comparison, 3 months ago those numbers were 22%, 9%, and 2%, respectively, and most of the state (67%) was in D0 - Abnormally Dry. This indicates an extreme lack of moisture over the past 3 months. The outlook through March, April, and May indicates much uncertainty in forecasting spring precipitation, with higher certainty predictions for above normal temperatures (NOAA Climate Prediction Center).

Producers should continue to check the Drought Monitor every Thursday for weekly updates, and also monitor the SDSU Extension Drought page for more drought information and management strategies.

The U.S. Drought Monitor map for South Dakota. The majority of the state is experiencing moderate drought, with pockets of severe to extreme drought in the Southeast and Southwest.

Figure 1. The U.S. Drought Monitor map for South Dakota as of February 4, 2021. Courtesy: U.S. Drought Monitor

Source : sdstate.edu

Video: Root Exudates, Soil Biology, and How Plants Recruit Microbes | Field Talk Friday

Field Talk Friday | Dr. John Murphy | Root Exudates, Soil Biology, and How Plants Recruit Microbes

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