Why climate predictions are so difficult

by Judith Curry

An insightful interview with Bjorn Stevens.

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What’s the worst case? Emissions/concentration scenarios

by Judith Curry

Is the RCP8.5 scenario plausible?

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What’s the worst case? A possibilistic approach

by Judith Curry

Are all of the ‘worst-case’ climate scenarios and outcomes described in assessment reports, journal publications and the media plausible? Are some of these outcomes impossible? On the other hand, are there unexplored worst-case scenarios that we have missed, that could turn out to be real outcomes? Are there too many unknowns for us to have confidence that we have credibly identified the worst case? What threshold of plausibility or credibility should be used when assessing these extreme scenarios for policy making and risk management?

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Why I don’t ‘believe’ in ‘science’

by Judith Curry

” ‘I believe in science’ is an homage given to science by people who generally don’t understand much about it. Science is used here not to describe specific methods or theories, but to provide a badge of tribal identity.  Which serves, ironically, to demonstrate a lack of interest in the guiding principles of actual science.” – Robert Tracinski

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Four fronts for climate policy

by Judith Curry

“For decades, scientists and policymakers have framed the climate-policy debate in a simple way: scientists analyse long-term goals, and policymakers pretend to honour them. Those days are over. Serious climate policy must focus more on the near-term and on feasibility.” – Y. Xu, V. Ramanathan, D. Victor

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Week in review – science edition

by Judith Curry

A few things that caught my eye this past week.

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Climate sensitivity calculator app

by Alberto Zaragoza Comendador

How sensitive is the Earth’s climate to greenhouse gases? Speaking about carbon dioxide in particular, how much would air temperatures increase if we doubled atmospheric concentrations of said gas?

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Week in review – science edition

by Judith Curry

A few things that caught my eye this past week.

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Hurricanes & climate change: 21st century projections

by Judith Curry

Final installment in my series on hurricanes and climate change.

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Week in review – science edition

by Judith Curry

A few things that caught my eye this past week.

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Solar input to high latitudes and the global ice volume

by Donald Rapp, Ralf Ellis and Clive Best

A review of the relationship between the solar input to high latitudes and the global ice volume over the past 2.7 million years.

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Hurricanes & climate change: recent U.S. landfalling hurricanes

by Judith Curry

An assessment of whether any of the impacts of recent  U.S. landfalling hurricanes were exacerbated by global warming.

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Critique of the new Santer et al. (2019) paper

by Ross McKitrick

Ben Santer et al. have a new paper out in Nature Climate Change arguing that with 40 years of satellite data available they can detect the anthropogenic influence in the mid-troposphere at a 5-sigma level of confidence. This, they point out, is the “gold standard” of proof in particle physics, even invoking for comparison the Higgs boson discovery in their Supplementary information.

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Hurricanes & climate change: landfalls

by Judith Curry

Part III: is there any signal of global warming in landfalling hurricanes and their impacts?

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Week in review – science edition

by Judith Curry

A few things that caught my eye the past 4(!) weeks.

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Hurricanes and Climate Change: Attribution

by Judith Curry

Part II:  what causes variations and changes in hurricane activity?

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Hurricanes & climate change: detection

by Judith Curry

I am preparing a new Special Report on Hurricanes and Climate Change.

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Sea level rise whiplash

by Judith Curry

Some recent sea level rise publications, with implications for how we think about the worst case scenario for the 21st century.

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Climate hypochondria and tribalism vs. ‘winning’

by Judith Curry

Some reactions from Wednesday’s Congressional testimony.

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Hearing – Climate Change: The Impacts and the Need to Act

by Judith Curry

The House Natural Resources Committee Hearing on Climate Change will be livestreamed on their Facebook page.

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Congressional hearings

by Judith Curry

I will be testifying on Wed in the House Natural Resources Hearing on Climate change.

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Reassessing the RCPs

by Kevin Murphy

A response to: “Is RCP8.5 an impossible scenario?”. This post demonstrates that RCP8.5 is so highly improbable that it should be dismissed from consideration, and thereby draws into question the validity of RCP8.5-based assertions such as those made in the Fourth National Climate Assessment from the U.S. Global Change Research Program.

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Week in review – science edition

by Judith Curry

A few things that caught my eye this past week.

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Early 20th century global warming

by Judith Curry

A careful look at the early 20th century global warming, which is almost as large as the warming since 1950.  Until we can explain the early 20th century warming, I have little confidence IPCC and NCA4 attribution statements regarding the cause of the recent warming.

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Is ocean warming accelerating faster than thought?

by Nic Lewis

*** UPDATE : response to comments by Zeke Hausfather appended

There are a number of statements in Cheng et al. (2019) ‘How fast are the oceans warming’, (‘the paper’) that appear to be mistaken and/or potentially misleading. My analysis of these issues is followed by a reply from the paper’s authors.

Contrary to what the paper indicates:

  • Contemporary estimates of the trend in 0–2000 m depth ocean heat content over 1971–2010 are closely in line with that assessed in the IPCC AR5 report five years ago
  • Contemporary estimates of the trend in 0–2000 m depth ocean heat content over 2005–2017 are significantly (> 95% probability) smaller than the mean CMIP5 model simulation trend.

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