The water vapour penny precipitates, almost, for Willis Eschenbach at WUWT

There's a new article at WUWT by Willis Eschenbach (archived here, latest here). It took him almost twenty years, but he's finally found the RSS total precipitable water (TPW) record. For years Willis has been arguing that Earth's climate can't change much because of thunderstorms. It seems that he may have finally woken up to the fact that there is more water vapour in a warmer atmosphere than in a cooler one and that this is contributing to the greenhouse effect. He wrote (about the dataset that was reported 20 years ago in 1996): "One of my great pleasures is to come across a new dataset."

I've been meaning to write about global warming, water vapour and precipitation for some time. There have been several papers on the subject (see below). What's happening is:

• the amount of water in the air is increasing as the world warms,
• the water cycle is intensifying,
• therefore there is more rain (and snow), and
• more greenhouse warming because water vapour is a strong greenhouse gas.

Warning: This is a rather long article, with no apologies :)

101 conspiracy theories about troposphere temperature: the RSS love affair is over

Over at WUWT there have been three articles about the lower troposphere temperatures. The first (archived here) was a Guest Post by Werner Brozek and Nick Stokes, Edited by Just The Facts with the title: "Long Satellite Pauses Ending (Now Includes January Data)".  The second article was about the February data for UAH (archived here, latest here). It had the wistful wishful title: "Global Temperature Report: Warmest Ever February 2016 driven by El Niño". The third article is the real doozy (archived here). It's by Anthony Watts so could well have some awful blunders in it. He's called his article: "The ‘Karlization’ of global temperature continues – this time RSS makes a massive upwards adjustment."

This article is a few hours late, and I'm not satisfied that I've got everything right because this is a subject on which I am feeling distinctly out of depth. Science deniers will try to tell you that there are little thermometers on satellites sending raw data to Earth and miraculously drawing temperature charts - or something like that. That's a pile of hogwash. The real story is much more complicated. Satellites come and go. Instruments change. Orbits decay. Temperature isn't measured directly, it's estimated from measurements from microwave sounding instruments (MSUs). What's reported is the result of complex calculations after adjustments and conversion to temperature. What we get are temperature trends in very thick layers in the atmosphere (kilometers thick, looking upwards into space), not the temperature of a particular spot or distinct level in the sky. Then there is "diurnal drift" - which is largely what the new paper by Carl Mears and Frank J. Wentz is all about.

Warning: this article is rather long. It explains the new RSS paper in more detail than I did in the previous article.