Temperature and water vapor variance scaling in global models: Comparisons to satellite and aircraft data

Variance spectral benchmarks for T and q obtained from the Atmospheric Infrared Sounder (AIRS) are compared to those generated by state-of-the-art numerical weather prediction "analyses" and "free-running" climate model simulations with spatial resolution comparable to AIRS.

The T and q spectra from both types of models are generally too steep such that small-scale variance is up to several factors smaller than AIRS. However, the two model analyses more closely resemble AIRS than the two free-running model simulations. Scaling exponents obtained for AIRS column water vapor (CWV) and height-resolved layers of q are also compared to the super-parameterized Community Atmospheric Model (SP-CAM) that highlight large differences in the magnitude of CWV variance and the relative flatness of height-resolved q scaling in SP-CAM.