Category Archives: Attribution

Overstretching Attribution

Posted on April 23, 2011 by curryja | 190 comments

by Judith Curry

Attribution of climate change and its impacts has been a recurring theme at Climate Etc. The first issue of Nature Climate Change has a provocative article entitled “Overstretching Attribution.”

Continue reading →

190 Comments

Posted in Attribution

Scafetta on climate oscillations

Posted on April 14, 2011 by curryja | 325 comments

by Judith Curry

David Hagen wrote on the Dempster thread:

There appears need for much more effort on grappling with both with major statistical issues involved (as highlighted by Dempster and Scafetta) as well as identifying natural causes that can have strong impacts on climate far beyond what is currently included in climate models (per Scafetta, and Svensmark).

As a case in point, lets examine one of Nicola Scafetta’s papers, which ties in with our previous threads on attribution of decadal variability.

Continue reading →

325 Comments

Posted in Attribution

Separating natural and anthropogenically-forced decadal climate variability

Posted on April 7, 2011 by curryja | 524 comments

by Judith Curry

The issue of separating natural from anthropogenically forced variability, particularly in context of the attribution of 20th century climate change, has been a topic of several previous threads at Climate Etc. The issue of natural vs anthropogenically forced climate variability/change has been a key issue of contention between the climate establishment and skeptics. There are some encouraging signs that the climate establishment is maturing in their consideration of this issue.

Continue reading →

524 Comments

Posted in Attribution, climate models

Reasoning about floods and climate change

Posted on March 15, 2011 by curryja | 151 comments

by Judith Curry

I just came across a paper that I view to be remarkably important, entitled “Influence diagrams for representing uncertainty in climate-related propositions,” by Hall, Twyman and Kay. This paper integrates a number of themes that we have been discussing here: reasoning about uncertainty, consilience of evidence, attribution of extreme events, floods, and even the Italian flag(!). And it does the best job I’ve seen of assessing uncertainty and confidence in a climate-related proposition.

Continue reading →

151 Comments

Posted in Attribution, Uncertainty

Extreme Testimony. Part II: Floods

Posted on March 9, 2011 by curryja | 153 comments

by Judith Curry

In Part I, the Congressional testimony of John Christy and Francis Zwiers on extreme events was discussed. In this post, I focus in on issues related to floods. This topic was also discussed in a previous post on Attribution of Extreme Events Part II.

Continue reading →

153 Comments

Posted in Attribution, Politics

Extreme testimony

Posted on March 8, 2011 by curryja | 341 comments

by Judith Curry

In today’s Hearing on “Climate Science and EPA’s Greenhouse Gas Regulations,” John Christy and Francis Zwiers both presented testimony that focused on extreme events, climate sensitivity and warming trends.

Continue reading →

341 Comments

Posted in Attribution, Politics

The Harry Potter Theory of Climate

Posted on March 2, 2011 by curryja | 489 comments

by Judith Curry

I just spotted spotted an article on Reuters entitled “The Harry Potter Theory of Climate,” and I couldn’t resist doing a post on it.

Continue reading →

489 Comments

Posted in Attribution

Attribution of Extreme Events: Part II

Posted on February 16, 2011 by curryja | 234 comments

by Judith Curry

In Part I, I was very unconvinced by strategies for attributing extreme events to global warming. Today, two new papers have been published in Nature that attribute the recent heavy rains to global warming. For a summary, see this article linked to at Huffington Post. The article said:

Continue reading →

234 Comments

Posted in Attribution

Attribution of extreme events

Posted on January 15, 2011 by curryja | 456 comments

by Judith Curry

Climate scientists have made public statements attributing extreme events to global warming. The first such attribution that I recall was made by Kevin Trenberth, to the effect that 7% of Hurricane Katrina’s intensity and rainfalls could be attributed to global warming. Trenberth has subsequently made public statements about the attribution to global warming of the Russian heatwave, Pakistan floods, and Queensland floods. Others have made similar public statements, most recently Richard Somerville.

NOAA is serious about including attribution of extreme events as part of its proposed National Climate Service. Their rationale is described in this Workshop summary:

Continue reading →

456 Comments

Posted in Attribution

Where’s the “missing” heat?

Posted on January 7, 2011 by curryja | 443 comments

by Judith Curry

I’m bowing to pressure to prepare a post on a current science topic that people seem to want to talk about. This topic refers to Kevin Trenberth’s infamous statement in the CRU emails:

The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.

Continue reading →

443 Comments

Posted in Attribution

Scenarios: 2010-2030. Part I

Posted on December 23, 2010 by curryja | 437 comments

by Judith Curry

On the time scale of a few decades ahead, regional variations in weather patterns and climate will be strongly influenced by natural internal variability. The potential applications of high resolution decadal climate change predictions are described in this CLIVAR doc. Based upon my own interaction with decision makers, I see a need on these time scales that is primarily associated with infrastructure decisions. Sectors that seem particularly interested in predictions on this time timescale are city and regional planners, the military, and the financial sector.

Continue reading →

437 Comments

Posted in Attribution, climate models, Uncertainty

Michaels’ controversial testimony: Part III

Posted on December 16, 2010 by curryja | 108 comments

by Judith Curry

Pat Michaels’ frequent collaborator, Chip Knappenberger, has written an extended post on MasterResource that is a follow up to Michaels’ testimony and Climate Etc. previous two threads. Chip has given me permission to repost in entirety at Climate Etc., and Chip will be available for discussion.

Continue reading →

108 Comments

Posted in Attribution

Michael’s controversial testimony: Part II

Posted on November 19, 2010 by curryja | 348 comments

by Judith Curry

Here is further explanation why I think Michael’s testimony is significant, and why I think the issue of the attribution since 1950 will be the battleground in U.S. CO2 policy. Michaell’s stated purpose for conducting this analysis was:

Continue reading →

348 Comments

Posted in Attribution