01/08/2024
By Lynne Schaufenbil
Please join the Lowell Center for Space Science and Technology for our Thursday Seminar Series during Spring 2024 semester!
The talk will be "The Ever-Present and Growing Threat of Flash Drought in an Accelerating Hydroclimate" by Prof. Jeffrey Basara, Dept Chair, Department of Environmental, Earth and Atmospheric Sciences, University of Massachusetts Lowell on Jan. 25 from 11 a.m. to noon in WAN305. RSVP to Lynne_Schaufenbil@uml.edu if you are interested in attending.
Abstract
Not all droughts are the same. In some cases, drought rapidly intensifies at subseasonal to seasonal scales with significant impacts to agriculture and water resources along with the increased propensity for heatwaves and wildfires. Like all droughts, flash drought begins with a precipitation deficit. However, both evaporative demand and soil moisture are critical flash drought variables, and identifying and monitoring the desiccation of the terrestrial surface is key for determining flash drought development and associated impacts. During flash drought, soil moisture can play two critical roles: (1) drought enhancement via dry soils, enhanced sensible heat flux, reduced evaporation, and enhanced vapor pressure deficit and, (2) drought resistance via moist soils that cool the surface via evaporation and decreased vapor pressure deficit. Yet, fundamental questions remain in the state of the science related to flash drought. For example, what is the overall relationship between atmospheric demand, evaporative stress, terrestrial desiccation, and precipitation in the progression of flash drought? Also, at what point during flash drought development does the environment transition from drought resistance (a negative feedback) to drought enhancement (a positive feedback) and vice versa? Finally, how will flash drought frequency and intensity evolve in a changing climate system?