Hansen wrote this recently :
We conclude that extreme heat waves, such as that in Texas and Oklahoma in 2011 and Moscow in 2010, were “caused” by global warming, because their likelihood was negligible prior to the recent rapid global warming. We discuss practical implications of this substantial, growing climate change.
That is easy enough to put to the test. I counted the number of 40C+ temperature readings in Oklahoma, at all GHCN HCN stations which have been continuously active since at least 1930. It turns out that 2011 was tenth hottest, and had fewer than half as many 40C readings as 1936, 1934 and 1955.
Hansen is either wildly incompetent, a liar, or both. He is counting on the fact that most people have little or no knowledge of history.