Category Archives: Attribution

Perils of apocalyptic thinking

by Judith Curry

The last time apocalyptic anxiety spilled into the mainstream to the extent that it altered the course of history — during the Reformation — it relied on a revolutionary new communications technology: the printing press. In a similar way, could the current surge in apocalyptic anxiety be attributed in part to our own revolution in communications technology?

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Aerosols and Atlantic aberrations

by Judith Curry

If Booth and colleagues’ results can be corroborated, then they suggest that multidecadal temperature fluctuations of the North Atlantic are dominated by human activity, with natural variability taking a secondary role. This has many implications. Foremost among them is that the AMO does not exist, in the sense that the temperature variations concerned are neither intrinsically oscillatory nor purely multidecadal.

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Meteorological March Madness

by Judith Curry

Nature’s exuberant smashing of daily high temperature records [in the U.S.] in recent weeks can only be described as “Meteorological March Madness”. Conditions more fitting of June than March prevailed east of the Rocky Mountains since the start of the month.  NOAA’s National Climate Data Center reported that over 7000 daily record high temperatures were broken over the U.S. from 1 March thru 27 March. 

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Missing(?) heat isn’t missing after all

by Judith Curry

Earth’s “missing heat” might not be missing after all.

That’s the conclusion of a new study that examines how accurately satellites and floating ocean instruments track the flow of energy from the sun to Earth and back again.

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The new climate dice

by Judith Curry

“Climate dice”, describing the chance of unusually warm or cool seasons relative to climatology, have become progressively “loaded” in the past 30 years, coincident with rapid global warming. The distribution of seasonal mean temperature anomalies has shifted toward higher temperatures and the range of anomalies has increased. 

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A biologist’s perspective on ice ages and climate sensitivity: Part I

by DocMartyn

This is the first of a three part presentation where I will attempt to explain the climate of the last 800,000 thousand years, drawing on the role of the biosphere’s response to interstellar dust.

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Candid comments from global warming scientists

by Judith Curry

Roger Pielke Sr has a fascinating, even mind-boggling, post that draws from an article by Paul Voosen in Greenwire entitled “Provoked scientists try to explain lag in global warming.”

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Self-organizing model of the atmosphere

by Frank Lemke

A recent post in our Global Warming Prediction Project discusses the question “What Drives Global Warming?” based on a self-organized interdependent nonlinear dynamic system of equations of 6 variables (ozone, aerosols, clouds, sun activity, CO2, global temperature). It also predicts using this system global warming 6 years ahead (monthly resolved) and it compares the known IPCC AR4 projections with this system prediction and the observed anomalies of the past 23 years.

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Santer on timescales of temperature trends

by Judith Curry

Santer et al. have a new paper in press entitled “Separating Signal and Noise in Atmospheric Temperature Changes: The Importance of Time Scale.”

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Extreme measures

by Judith Curry

[I]n the past year, climate researchers in the United States and Britain have formed a loose coalition under the banner ‘ACE’ — Attribution of Climate-related Events — and have begun a series of coordinated studies designed to lay the foundations for a systematic weather-attribution programme.

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Weather weirding: back to the 1950′s

by Judith Curry

Seth Borenstein at AP published an article  entitled “Nature’s extremes worse than usual in US this year.”  I have a quote in the article:

Judith Curry of Georgia Tech disagreed, saying that while humans are changing the climate, these extremes have happened before, pointing to the 1950s.  “Sometimes it seems as if we have weather amnesia,’’ she said.

Here is a more complete context for that quote.

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On the attribution of flood peaks

by Judith Curry

The hypothesized link between a warming climate and increased frequency and magnitude of floods goes something like this:  a warmer climate is associated with more water vapor in the atmosphere, which means more rainfall and more floods.  Is there any observational support for this link?

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Cyclomania

by Judith Curry

The thread on the recent Loehle and Scafetta paper (here and WUWT) have spawned the term “cyclomania” in the context of searches for natural cycles that can explain 20th century climate change and potentially predict climate change in the 21st century.

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Loehle and Scafetta on Climate Change Attribution

by Craig Loehle

How do we detect the influence of humans on the climate system?  Current methods based on climate models are unfortunately circular: their estimate of human effects is only valid if the models are correct, but the models make certain assumptions and also are fitted to the historical temperature record.  A model-independent estimate of climate response is needed and is provided by this study.

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Essay on “Our evolving climate”

by Judith Curry

This article aims to portray and communicate the important role played by natural variability in our evolving climate. Understanding and acknowledging these variations is important for society and policymakers. Much of this variability is chaotic and unpredictable but some significant fraction is potentially predictable, providing an opportunity to narrow the uncertainty in climate predictions of the coming decade.

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Time-varying trend in global mean surface temperature

by Judith Curry

Two key questions in the climate debate are:

  • How much of the recent warming can be attributed to natural variability versus anthropogenic forcing?
  • Is the rate of warming in the latter half of the 20th century unusual or unprecedented?

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An explanation(?) for lack of warming since 1998

by Judith Curry

A new paper has been published in PNAS entitled “Reconciling anthropogenic climate change with observed temperature 1998-2008.”

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Climate Change, Extreme Weather Linked(?) at Last

by Judith Curry

The title for this post comes from a post at Pew Climate, highlighting a big three-part series featured on ScientificAmerican.com  to explain the link between climate change extreme weather.

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Sea Level Hockey Stick

by Judith Curry

A new paper on sea level variations over the past two millennia is receiving substantial attention.

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Overconfidence in IPCC’s detection and attribution. Part IV

by Judith Curry

Last October, I introduced this topic in Part I and followed up with Part II and Part III, which formed an early draft of an argument I was using in a paper entitled “Climate Science and the Uncertainty Monster.”  I’ve gotten the reviews back on my paper, this post is a draft of the revised version of that particular section.

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