Open AccessComparison of Stratospheric Aerosol and Gas Experiment (SAGE) II version 6.2 water vapor with balloon‐borne and space‐based instruments
Author(s) -
Taha Ghassan,
Thomason Larry W.,
Burton Sharon P.
Publication year - 2004
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 - 10.1029/2004jd004859
Subject(s) - water vapor , hygrometer , stratosphere , aerosol , atmospheric sciences , environmental science , meteorology , extinction (optical mineralogy) , altitude (triangle) , frost (temperature) , ozone , remote sensing , humidity , physics , optics , geology , mathematics , geometry
A new version of the SAGE II data products was released in October 2003. The primary change to the algorithm dealt with improvements in the water vapor product such as eliminating the dry bias in the lower stratosphere and reducing the sensitivity to aerosol contamination. Results of an extensive comparison of SAGE II version 6.2 water vapor and various correlative measurement from balloon‐borne and space‐based instruments illustrate significant improvement over the previous version (version 6.1). In general, the agreement was within 10% or less over an altitude range of 15–40 km when compared with frost point hygrometer, HALOE, POAM III, and ILAS and 15–20% when compared to MkIV. Above 40 km, SAGE II water vapor profiles are often noisy and show an increasingly positive bias. On the basis of comparison with HALOE a basic screening criteria would consist of electing measurements where the aerosol extinction coefficient at 1020 nm exceeds 2 × 10 −4 km −1 and water vapor uncertainty exceeds 50%.