New misguided interpretations of the greenhouse effect from William Kininmonth

ms: It is therefore wrong and foolish to claim that a 1°C warmer atmosphere increases the H2O content by 7%.

BPL: Look again.

Brown, S., S. Desai, S. Keihm, and C. Ruf (2007), Ocean water vapor and cloud burden trends derived from the topex microwave radiometer. Geoscience and Remote Sensing Symposium 2007, Barcelona, Spain, IGARSS 2007, IEEE International, 886-889.

Mears, C., J. Wang, S. Ho, L. Zhang, and X. Zhou, 2010: Total column water vapor [in “State
of the Climate in 2009”]. Bull. Amer. Meteor. Soc., 91 (6), S79–S82.

A more robust analysis of water vapour changes by Mears et al. (2010) shows that total column water vapour is increasing over the oceans in the period 1988-2009 at a rate of 0.27 +/- 0.08 mm/decade. This corresponds to about 1.2%/decade (IPCC, 2007).

Wang, J.; Dai, A.; Mears, C. 2016. Global water vapor trend from 1988 to 2011 and its diurnal asymmetry based on GPS, radiosonde, and microwave satellite measurements. J. Climate 29, 5205-5222.

“It is found that positive PW trends predominate over the globe, with larger magnitudes over ocean than over land. The PW trend is correlated with surface warming spatially over ocean with a pattern correlation coefficient of 0.51.”

Chen, B., Liu, Z. 2016. Global water vapor variability and trend from the latest 36 year (1979 to 2014) data of ECMWF and NCEP reanalyses, radiosonde, GPS, and microwave satellite. J. Geophys. Res. 121, 11,442-11,462.

The variability and trend in global precipitable water vapor (PWV) from 1979 to 2014 are analyzed using the PWV data sets from the ERA-Interim reanalysis of the European Centre for Medium-Range Weather Forecasts (ECMWF), reanalysis of the National Centers for Environmental Prediction (NCEP), radiosonde, Global Positioning System (GPS), and microwave satellite observations. PWV data from the ECMWF and NCEP have been evaluated by radiosonde, GPS, and microwave satellite observations, showing that ECMWF has higher accuracy than NCEP. Over the oceans, ECMWF has a much better agreement with the microwave satellite than NCEP. An upward trend in the global PWV is evident in all the five PWV data sets over three study periods: 1979–2014, 1992–2014, and 2000–2014. Positive global PWV trends, defined as percentage normalized by annual average, of 0.61?±?0.33%?decade-1, 0.57?±?0.28%?decade-1, and 0.17?±?0.35%?decade-1, have been derived from the NCEP, radiosonde, and ECMWF, respectively, for the period 1979–2014. It is found that ECMWF overestimates the PWV over the ocean prior to 1992. Thus, two more periods, 1992–2014 and 2000–2014, are studied. Increasing PWV trends are observed from all the five data sets in the two periods: 1992–2014 and 2000–2014. The linear relationship between PWV and surface temperature is positive over most oceans and the polar region. Steep positive/negative regression slopes are generally found in regions where large regional moisture flux divergence/convergence occurs.