Publications

Wu, J; Kurosaki, Y; Sekiyama, TT; Maki, T (2023). Effects of Dry Vegetation Coverage Estimated from the MODIS Soil Tillage Index on Dust Occurrence: Verification by Surface Synoptic Observations. JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 101(1), 67-77.

Abstract
In drylands, the dry vegetation coverage affects dust occurrence by modulating threshold friction velocity (or wind speed) for dust emission. However, research into quantifying the effect of dry vegetation coverage on dust occurrence is scarce. This study investigated the spatial and temporal variations of dust occurrence and three defi-nitions of strong wind frequency over the Gobi Desert and surrounding regions in March and April, months when dust occurrence is frequent, during 2001 - 2021. We evaluated the effects of variations in dry vegetation on dust occurrence using the threat scores of forecasted dust occurrences for each strong wind definition. Our results in-dicated that dry vegetation, which was derived from the MODIS Soil Tillage Index, affects dust occurrence more significantly in April than in March. In March, land surface parameters, such as soil freeze-thaw and snow cover, in addition to dry vegetation coverage, should be considered to explain dust variations in that month. However, using the threshold wind speed estimated from dry vegetation coverage improved the prediction accuracy of dust occurrence in April. Therefore, we propose that the dry vegetation coverage is a key factor controlling dust oc-currence variations in April. The findings indicate that estimation of dry vegetation coverage should be applied to dust models.

DOI:
10.2151/jmsj.2023-004

ISSN:
2186-9057