Water sources and land capacitor effects stimulate observed summer Arctic moistening and warming
Abstract The primary sources of recent summer Arctic moistening trends in reanalysis are uncertain, hindering attribution of observed Arctic warming due to radiative effects from water vapor changes. Here, we use a combined online numerical water tracer and circulation nudging approach in the Community Earth System Model to track the sources of water vapor beyond its initial sources. Trends in boreal summer large-scale circulation have driven moistening of the Arctic over recent decades, having a large impact on the Arctic radiative budget, accounting for 94% of the strengthening water vapor radiative feedback. We identify two key regions supplying the Arctic water vapor feedback: Northeast North America and western/central Eurasia. In both regions, anticyclonic circulations over the southwest Atlantic and eastern Europe move moisture from the tropical oceans poleward to high latitude land through precipitation in winter and spring. During summer, evapotranspiration over land releases this water vapor, and it is transported by winds into the Arctic. We refer to this sequence of terrestrial moisture storage and release as the land capacitor effect. Thus, the impacts of circulation changes on poleward moisture transport and land-atmosphere interactions over high latitudes represent the underlying mechanisms of the recent moistening and warming in the Arctic.
Authors
- Ian Baxter (ORCID: https://orcid.org/0000-0002-1702-2471)
- Bin Guan (ORCID: https://orcid.org/0000-0002-8428-5984)
- Qinghua Ding (ORCID: https://orcid.org/0000-0003-3634-0181)
- Yutian Wu (ORCID: https://orcid.org/0000-0002-4428-6624)
- Nicole Feldl (ORCID: https://orcid.org/0000-0002-2631-1419)
- Marika M. Holland (ORCID: https://orcid.org/0000-0001-5621-8939)
- Thomas J. Ballinger (ORCID: https://orcid.org/0000-0002-8722-1927)
- Hailong Wang (ORCID: https://orcid.org/0000-0002-1994-4402)
- Zhe Li (ORCID: https://orcid.org/0000-0001-7607-1559)
- Jennifer E. Kay (ORCID: https://orcid.org/0000-0002-3625-5377)
- Jiang Zhu (ORCID: https://orcid.org/0000-0002-0908-5130)
- Hailan Wang (ORCID: https://orcid.org/0000-0003-1041-0233)
Institutions
- NSF National Center for Atmospheric Research (US)
- Jet Propulsion Laboratory (US)
- University of Alaska Fairbanks (US)
- Pacific Northwest National Laboratory (US)
- Lamont-Doherty Earth Observatory (US)
- University of California, Santa Barbara (US)
- University of California, Los Angeles (US)
- Cooperative Institute for Research in Environmental Sciences (US)
- University of California, Santa Cruz (US)
- University of Colorado Boulder (US)
- NOAA National Centers for Environmental Prediction (US)
- NSF NCAR Climate and Global Dynamics Laboratory (US)
- NOAA Climate Prediction Center
- Columbia University (US)
Publication Details
- Journal
- Communications Earth & Environment
- Published
- 2025-12-03
- DOI
- https://doi.org/10.1038/s43247-025-03000-x
- Primary Topic
- Climate change and permafrost
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- U.S. Department of Energy
- National Aeronautics and Space Administration
- Battelle
- Department of Water Resources
- Pacific Northwest National Laboratory