James Hansen: Extreme Weather Linked to Climate Change

NASA scientist James Hansen, considered to be the 'godfather of global warming' has co-authored a new report that shows the connection between 'extreme weather events', such as the drought most of the U.S. is now experiencing, and climate change.

In a report released on August 6 in the prestigious Proceedings of the National Academy of Sciences (PNAS), James E. Hansen, who directs the NASA Goddard Institute for Space Studies, makes the connection between what is termed 'extreme weather events', such as heat waves and droughts, and climate change.

In this video interview with the News Hour's Hari Sreenivasan, Hansen is asked, "....Explain how we know that these (extreme) events are ...not part of any natural cycle?"

"They are in fact a product of global warming and we can see that very easily", Hansen decisively answers.

In his August 3, Washington Post opinion, Climate change is here - and worse than we thought, Hansen makes the climate change-extreme weather connection clear.

"When I testified before the Senate in the hot summer of 1988, I warned of the kind of future that climate change would bring to us and our planet...My projections about increasing global temperature have been proved true.

Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change."

His view is not universally shared.

In his widely read "total turnaround" by climate skeptic, Richard Muller, states in his July 28, New York Times opinion, "The Conversion of a Climate-Change Skeptic, "...the recent warm spell in the United States happens to be more than offset by cooling elsewhere in the world, so its link to "global" warming is weaker than tenuous."

Hansen's paper may very well change the bar from discussing what the effects of global warming will be to what they are now.

Full Story: James Hansen: Extreme Heat Events Connected to Climate Change



Muller On The Recent Hot Spell

Richard Muller, states ... "...the recent warm spell in the United States happens to be more than offset by cooling elsewhere in the world, so its link to “global” warming is weaker than tenuous."

Muller's comment doesn't make sense to me. His own numbers show that average land temperature has increased 2.5 degrees farenheit in the last 250 years. Is he seriously claiming that it the current hot spell would have been just as likely if temperature had not increased at all in the last 250 years?

Muller seems to be talking only about warming and cooling in different parts of the world during this year. That is irrelevant to the question of whether the current hot spell was caused by the global warming that has occurred since 1980, as Hansen claims.

Incidentally, isn't it a bit inaccurate to call it a "warm spell," as Muller does. Temperatures are exceeding 110 degrees, and I would call that hot, not warm.

Charles Siegel


Richard Muller, states ... "...the recent warm spell in the United States happens to be more than offset by cooling elsewhere in the world, so its link to “global” warming is weaker than tenuous." Reference? Where does Muller get that? The anomaly map I found shows warming worldwide.


We’re Already Topping Dust Bowl Temperatures due to 1.5 deg F warming — imagine what’ll happen If we fail to stop 10°F warming, which is where we are heading.!!

How to stop 10 degree warming? Dr. James Hansen head of NASA (remember NASA …they got us to the moon?) said we would have a serious climate problem in 1988. He underestimated the problem.

He currently supports a “carbon fee and dividend” program. It is the Save Our Climate Act HR3242. Putting a fee on carbon, at its source, shifts the market to renewable energy. And it is a part of a free market solution, because it dings coil and oil for just part of the social costs that we have been paying.

I don’t think it has a prayer in this Congress, however, because the Republican House will oppose it. The program doesn’t tax the average American. All fees on carbon are used to REDUCE our taxes. It’s just that Dirty Energy doesn’t like it, and fellows like James Inhofe, with the help of Muller, are just the hit men to kill it.

Irvin Dawid's picture

NYT: Thorough critique of Hansen's "Perception of climate change

NYT reporter Justin Gilles, who has written several climate change articles recently, provides an excellent context for Hansen's new study in his August 7 article, "Study Finds More of Earth Is Hotter and Says Global Warming Is at Work. The end of the article leaves the reader questioning the climate change-extreme weather association that Hansen is so certain of.

"Martin P. Hoerling, a researcher with the National Oceanic and Atmospheric Administration who studies the causes of weather extremes, said he shared Dr. Hansen’s general concern about global warming. But he has in the past criticized Dr. Hansen for, in his view, exaggerating the connection between global warming and specific weather extremes. In an interview, he said he felt that Dr. Hansen had done so again.

Dr. Hoerling has published research suggesting that the 2010 Russian heat wave was largely a consequence of natural climate variability, and a forthcoming study he carried out on the Texas drought of 2011 also says natural factors were the main cause.

Dr. Hoerling contended that Dr. Hansen’s new paper confuses drought, caused primarily by a lack of rainfall, with heat waves."

“This isn’t a serious science paper,” Dr. Hoerling said. “It’s mainly about perception, as indicated by the paper’s title. Perception is not a science.”

Irvin Dawid, Palo Alto, CA

NYT Provides the Usual Balance About Hansen's Findings

First, it is not quite accurate to say: "The end of the article leaves the reader questioning the climate change-extreme weather association that Hansen is so certain of."

The end of the article questions the association of climate change with any specific extreme-weather event. It does not question the fact that climate change will generally make extreme weather events more common.

Second, the article provides the usual journalistic balance, quoting one expert who agrees with Hansen's conclusion that you can tie specific events to climate change (Weaver), and then quoting another who says you cannot (Hoerling). It doesn't say that Hoerling is right and Weaver is wrong.

I am certainly not enough of an expert on statistical analysis to say whether Hansen or Hoerling is right about whether the Russian hot spell of 2010 should be attributed to global warming or to random variations in weather.

But apart from these arguments about specific events, it is very clear global warming causes a general increase in extreme weather events - which itself is a good reason to control global warming.

Charles Siegel

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