Table 2. The Different Data Sets of Water Vapor Isotopic Composition Retrieved By Satellite Instruments That We Useda Data Set Reference Level Spatial Coverage or Location Period Precision Footprint Comparison Methodology SCIAMACHY Frankenberg et al. [2009] total column, mainly sensitive in the boundary layer global 2003-2005 40permil-100permil, reduced by averaging 120 x 20 km collocation TES Worden et al. [2007] 600 hPa global 2004-2008 10-15permil, reduced by averaging 5.3 x 8.5 km collocation, convolution with kernels ACE Nassar et al. [2007] down to 500 hPa global, but small number of measurements 2003-2008 about 50permil, reduced by averaging limb measurement collocation, smoothing MIPAS Steinwagner et al. [2010] down to 300 hPa global September 2002-March 2004 about 50permil, reduced by averaging limb measurement collocation, convolution with kernels aThe period indicates that used in our analysis, which can be shorter than the total data set.