More heat means more water vapor which means more extreme weather

flood pakistan by DVIDSHUB

New York Times front-page story: In Weather Chaos, a Case for Global Warming! – Trenberth: “It’s not the right question to ask if this storm or that storm is due to global warming, or is it natural variability. Nowadays, there’s always an element of both.”
[Via Climate Progress]

The floods battered New England, then Nashville, then Arkansas, then Oklahoma — and were followed by a deluge in Pakistan that has upended the lives of 20 million people.

The summer’s heat waves baked the eastern United States, parts of Africa and eastern Asia, and above all Russia, which lost millions of acres of wheat and thousands of lives in a drought worse than any other in the historical record.

Seemingly disconnected, these far-flung disasters are reviving the question of whether global warming is causing more weather extremes.

The collective answer of the scientific community can be boiled down to a single word: probably.

That’s the opening of “In Weather Chaos, a Case for Global Warming!“ It is one of the better recent major media articles on global warming and extreme weather — and the best front page New York Times climate article in years.

The NYT is clearly making a major statement since not only is this “above the fold,” but it takes up most of the front page with large photos of what’s happening in Pakistan and Russia and the U.S. (see Russian Meteorological Center: “There was nothing similar to this on the territory of Russia during the last one thousand years in regard to the heat.” and Hottest* July in RSS satellite record, record floods swamp Pakistan, U.S. set 1480 temperature records in past two months, and 2010 breaks 2007 record for most nations setting all-time temperature records):


The water cycle will be accelerated due to a warmer climate, putting more water in the air because the higher temperatures allow more water to be carried. Of course, water vapor is an even greater greenhouse gas that CO2 but, unlike CO2, it precepitates out as rain and snow.

So, what this means is that more water carried in the atmosphere will be dropped as rain or snow on the landscapes. One of the expected signs of climate change would be more extreme precipitation events. We saw record snows in the US this winter and noe amazing rains in Pakistan this summer.

We can not prove today that these events are due to climate change but they are the sorts of events we would expect to see. And we will expect to see more of them in the future.

Once in a century event may happen much more often.

And the thing to remember is that scientists are, as a group, very conservative about what they state, If they get it wrong, that could be the end of their career. As the blog post states, when commenting on why scientists often require more proof than people:

That is a distinction always worth remembering. The scientific literature is primarily filled with that which can be proven — and most climate scientists are unwilling to make public statements that go beyond what can be proven. That is a key reason so much of the scientific literature is conservative or understates what is likely to come on our current path of unrestricted emissions. And that goes double for reviews of the scientific literature that must be signed off on word for word by major governments, like the IPCC.

The tough thing is that these changes can happen pretty fast and they will probably not return to normal, even if we magically reduced the amount of CO2 in the atmosphere back to pre-industrial age levels. There is already so much CO2 and excess heat in the system that it could take hundreds of years to shed it.

The areas of the world that will most likely have to deal with these extremes are also some of the most politically unstable so things will not be easy.

I believe that we can solve almost anything if we actually work together and decide to. Perhaps now, more people will be willing to help instead of hinder.