07/02/2026
By Jordin Hubbard

The Kennedy College of Sciences, Department of Environmental, Earth and Atmospheric Sciences, invites you to attend a Master’s thesis defense by Jordin Hubbard on “Investigation of Rapidly Developing Warm Season Drought in the Northeast United States.”

Candidate Name: Jordin Hubbard
Degree: Master of Science in Environmental Studies, Atmospheric Science Option
Defense Date: Thursday, July 16, 2026
Time: 12 p.m. (noon)
Location: Olney Hall, Room 212

Committee:

  • Advisor: Jeffrey B. Basara, Ph.D., Professor and Department Chair, Department of Environmental, Earth and Atmospheric Sciences, University of Massachusetts Lowell
  • Christopher B. Skinner, Ph.D., Department of Environmental, Earth and Atmospheric Sciences, University of Massachusetts Lowell
  • Frank P. Colby, Ph.D., Department of Environmental, Earth and Atmospheric Sciences, University of Massachusetts Lowell

Brief Abstract:
Drought is changing in the northeast United States (NEUS). Although the region normally receives 10 cm of liquid precipitation each month, the past decade has shown a notable change in the climatological record including three rapidly developing warm season droughts in 2016, 2020, and 2022. To examine this shift and better understand drought in the NEUS, multiple datasets were used, including PRISM (precipitation and temperature), ERA5-Land reanalysis (potential evapotranspiration), Harvard Forest Flux Tower observations (latent heat fluxes and net radiation), United States Geological Survey (USGS) National Water Information System (NWIS) streamflow data, and satellite remote sensing observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) to evaluate vegetation responses (Land Surface Water Index; LSWI).
Analysis of PRISM data reveals that the 2016, 2020, and 2022 events in New England were significant when compared to the long-term record. Key characteristics of these events include high temperatures, precipitation deficits, low streamflow, and increased atmospheric demand as shown by increased potential evapotranspiration and net radiation. Despite these conditions, observations from the Harvard Forest EMS Flux Tower (HFR1) show that latent heat fluxes during each event remained near or above climatological norms, yielding increased evapotranspiration (ET). This is supported by LSWI data, which shows enhanced greening in some areas despite persistent drought conditions reported by the United States Drought Monitor (USDM), precipitation deficits, and increased atmospheric demand. As such, drought impacts were first identified in the streamflow, rather than the vegetation, as streamflow quickly dropped below the 40th percentile from April to May, with the average of gauges in each state remaining below this threshold for the duration of the event, and below the 20th percentile in most states throughout the summer. This physical response, consistent amongst the three events, points to complex land-atmosphere interactions driven by atmospheric demand and greater reliance on groundwater use as overall drought stress increases during flash drought in the northeast United States.