Open AccessImpact of improved near‐infrared water vapor line data in simulations with the ECHAM4 general circulation model
Author(s) -
Lohmann Ulrike,
Bennartz Ralf
Publication year - 2002
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2001jd001101
Subject(s) - hitran , water vapor , environmental science , meteorology , infrared , atmospheric sciences , absorption (acoustics) , remote sensing , absorption spectroscopy , physics , optics , geology
Recently, two new water vapor line absorption data sets have become available. First, the HITRAN 2000 data set provides updated information on several water vapor absorption lines in the near infrared. Second, an independent study initiated by the European Space Agency (ESA) created a new line data set for the spectral range between 8592 and 20000 cm −1 . We investigate the impact of these new data in the near infrared as compared to HITRAN‐92 on the absorption of solar radiation in the ECHAM4 general circulation model. Owing to the increased water vapor absorption in the new parameterizations, the global annual mean atmospheric absorption of solar radiation in ECHAM4 is increased under all skies between 3.2 and 3.7 W m −2 and between 5.0 and 5.7 W m −2 under clear skies for the different data sets. While the dynamics barely change, the hydrological cycle is slightly weaker, the cloud cover has decreased by 0.4% and the precipitation by 0.06 to 0.08 mm d −1 when the new data sets are used.