Climate Dynamics Group
 at the University of California, Santa Cruz

Poleward moisture transport into the Arctic occurs via short-lived, episodic intrusions of warm, moist air masses. These extreme transport events are associated with an enhanced greenhouse effect that is expected to slow sea-ice growth in winter and hasten the start of spring melt season. Yet, their impact on the Arctic energy balance averaged over longer time scales has been difficult to quantify, in part due to the challenge in separating local and remote Arctic moisture sources. We implement numerical water tracers and source-aware radiative locking in an Earth system model to reveal how moist intrusions and their vertical structure sustain water vapor and cloud feedbacks over the Arctic and thereby elicit sea ice retreat and its attendant feedbacks. This research is supported by the Department of Energy under Award DE-SC0023070.

Numerical water tracers in the atmospheric component of the Energy Exascale Earth System Model: Implementation and changes in moisture origin
research paper
  • Alexandre Audette
  • Nicole Feldl
  • Hansi Singh
  • Kyle Heyblom
  • Hailong Wang
  • Jesse Nusbaumer
  • Hui Wan
  • Kai Zhang

Abstract to come.

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Quantifying moisture sources of Arctic atmospheric rivers during the recent historical period
research paper
  • Weiming Ma
  • Hailong Wang
  • Shixuan Zhang
  • Balwinder Singh
  • Yun Qian
  • Yiling Huo
  • Nicole Feldl
  • Alexandre Audette

Atmospheric rivers (ARs), filaments of intense atmospheric moisture transport, play a significant role in delivering moisture poleward into the Arctic and triggering weather extremes. Although previous studies have focused on large-scale circulations driving these events, this study investigates ARs through attributing their moisture sources using the Community Atmosphere Model version 5 (CAM5) with moisture-tagging capability. Examining ARs in the Atlantic and Pacific sectors of the Arctic separately revealed distinct contributions from remote versus local, and ocean versus land, moisture sources. Unlike non-AR events, Arctic ARs primarily draw moisture from their respective ocean basins in lower-latitude regions during the cold season, and shift to land sources in the warm season. Cold-season ARs in the Atlantic and Pacific sectors source 73.2% and 85.3% of their moisture from... read more →