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Title: Relationships among climatological vertical moisture structure, column water vapor, and precipitation over the central Amazon in observations and CMIP5 models

Bias and spread in Coupled Model Intercomparison Project Phase 5 simulated vertical specific humidity (q) structure are examined and related to both precipitation and column water vapor (cwv) near Manaus, Brazil, site of the recent Green Ocean Amazon campaign. Simulated seasonal mean q profiles are typically too dry, especially at low levels and during the local dry season, consistent with previously identified surface hydroclimate biases in the Amazon. Multimodel empirical orthogonal function analysis of the models' monthly climatological q profiles indicates two significant modes of ensemble spread in moisture vertical structure, with the leading mode peaked at low levels and the second mode in the lower free troposphere (LFT). While both modes project onto simulated cwv spread, only the first projects on precipitation, suggesting inconsistent sensitivity of simulated rainfall to LFT moisture. Finally, relative to observations, models with high cwv and low-level moisture errors tend to exhibit high precipitation error.
ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [3] ; ORCiD logo [1] ; ORCiD logo [4] ; ORCiD logo [3]
  1. Rutgers Univ., New Brunswick, NJ (United States). Dept. of Environmental Sciences
  2. Univ. Nacional Autonoma de Mexico (UNAM), Mexico City (Mexico). Centro de Ciencias de la Atmósfera
  3. Univ. of California, Los Angeles, CA (United States). Dept. of Atmospheric and Oceanic Sciences
  4. Fundação Centro de Análise, Manaus (Brazil). Pesquisa e Inovação Tecnológica Faculdade Fucapi
Publication Date:
Grant/Contract Number:
SC0011069; SC0011074; AGS-1505198
Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 44; Journal Issue: 4; Journal ID: ISSN 0094-8276
American Geophysical Union
Research Org:
Rutgers Univ., New Brunswick, NJ (United States)
Sponsoring Org:
USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR) (SC-21); National Science Foundation (NSF)
Country of Publication:
United States
54 ENVIRONMENTAL SCIENCES; Amazon; vertical moisture structure; precipitation; column water vapor; CMIP5 models
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1402141