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Title: Fog and rain in the Amazon

The diurnal and seasonal water cycles in the Amazon remain poorly simulated in general circulation models, exhibiting peak evapotranspiration in the wrong season and rain too early in the day. We show that those biases are not present in cloud-resolving simulations with parameterized large-scale circulation. The difference is attributed to the representation of the morning fog layer, and to more accurate characterization of convection and its coupling with large-scale circulation. The morning fog layer, present in the wet season but absent in the dry season, dramatically increases cloud albedo, which reduces evapotranspiration through its modulation of the surface energy budget. Finally, these results highlight the importance of the coupling between the energy and hydrological cycles and the key role of cloud albedo feedback for climates over tropical continents.
 [1] ;  [2] ;  [2] ;  [1]
  1. Columbia Univ., Palisades, NY (United States); Columbia Univ., New York, NY (United States)
  2. Columbia Univ., New York, NY (United States)
Publication Date:
Grant/Contract Number:
SC0011094; FOA-0000885
Published Article
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Volume: 112; Journal Issue: 37; Journal ID: ISSN 0027-8424
National Academy of Sciences, Washington, DC (United States)
Research Org:
Columbia Univ., New York, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Country of Publication:
United States
54 ENVIRONMENTAL SCIENCES; land−atmosphere interactions; Amazon; hydrologic cycle; fog; cloud-resolving models
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1348828