The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners.
As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
i
Flash Drought in CMIP5 Models
-
2021
-
Source: Journal of Hydrometeorology, 22(6), 1439-1454
[PDF-5.77 MB]
Details:
-
Alternative Title:‘‘Flash drought’’ (FD) describes the rapid onset of drought on subseasonal times scales. It is of particularinterest for agriculture because it can deplete soil moisture for crop growth in just a few weeks. To better understand theprocesses causing FD, we evaluate the importance of evaporative demand and precipitation by comparing three differentdrought indices that estimate this hazard using meteorological and hydrological parameters from the CMIP5 suite ofmodels. We apply the standardized precipitation index (SPI); the evaporative demand drought index (EDDI), derived fromevaporative demandE0; and the evaporative stress index (ESI), which connects atmospheric and soil moisture conditions bymeasuring the ratio of actual and potential evaporation. The results show moderate-to-strong relationships (r2.0.5)between drought indices and upper-level soil moisture on daily time scales, especially in drought-prone regions. We find thatall indices are able to identify FD in the top 10-cm layer of soil moisture in a similar proportion to that in the models’climatologies. However, there is significant intermodel spread in the characteristics of the FDs identified. This spread ismainly caused by an overestimation ofE0, indicating stark differences in the land surface models and coupling in individualCMIP5 models. Of all indices, the SPI provides the highest skill in predicting FD prior to or at the time of onset in soilmoisture, while both EDDI and ESI show significantly lower skill. The results highlight that the lack of precipitation is themain contributor to FDs in climate models, withE0playing a secondary role.
-
Journal Title:Journal of Hydrometeorology
-
Personal Author:
-
NOAA Program & Office:
-
Description:‘‘Flash drought’’ (FD) describes the rapid onset of drought on subseasonal times scales. It is of particularinterest for agriculture because it can deplete soil moisture for crop growth in just a few weeks. To better understand theprocesses causing FD, we evaluate the importance of evaporative demand and precipitation by comparing three differentdrought indices that estimate this hazard using meteorological and hydrological parameters from the CMIP5 suite ofmodels. We apply the standardized precipitation index (SPI); the evaporative demand drought index (EDDI), derived fromevaporative demandE0; and the evaporative stress index (ESI), which connects atmospheric and soil moisture conditions bymeasuring the ratio of actual and potential evaporation. The results show moderate-to-strong relationships (r2.0.5)between drought indices and upper-level soil moisture on daily time scales, especially in drought-prone regions. We find thatall indices are able to identify FD in the top 10-cm layer of soil moisture in a similar proportion to that in the models’climatologies. However, there is significant intermodel spread in the characteristics of the FDs identified. This spread ismainly caused by an overestimation ofE0, indicating stark differences in the land surface models and coupling in individualCMIP5 models. Of all indices, the SPI provides the highest skill in predicting FD prior to or at the time of onset in soilmoisture, while both EDDI and ESI show significantly lower skill. The results highlight that the lack of precipitation is themain contributor to FDs in climate models, withE0playing a secondary role.
-
Keywords:
-
Source:Journal of Hydrometeorology, 22(6), 1439-1454
-
DOI:
-
Document Type:
-
Rights Information:Other
-
Compliance:Submitted
-
Main Document Checksum:
-
Download URL:
-
File Type:
