Category Archives: Sensitivity & feedbacks

Hothouse Earth

by Judith Curry

We need to raise the bar on how we think about the possible worst case scenario for climate change.

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Impact of recent forcing and ocean heat uptake data on estimates of climate sensitivity

by Nic Lewis

We have now updated the LC15 paper with a new paper that has been published in the Journal of Climate “The impact of recent forcing and ocean heat uptake data on estimates of climate sensitivity“.  The paper also addresses critiques of LC15.

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Emergent constraints on climate sensitivity in global models. Part III

by Nic Lewis

The two strongest potentially credible constraints, and conclusions.

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Emergent constraints on climate sensitivity: Part II

by Nic Lewis

The four constraints that Caldwell assessed as credible.

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Emergent constraints on climate sensitivity: Part I

by Nic Lewis

Emergent constraints on climate sensitivity:  their nature and assessment of validity.

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Recent research on aerosol forcing of the CMIP5 models

by Frank Bosse

A few days ago a paper (Sato et al) dealing with some aspects of the “Aerosol Cloud Interactions”, (ACI, also called “aerosol indirect effects”) was released. It bolsters the conclusions of earlier papers: the effective radiative forcing from ACI (ERFaci) is smaller than thought, perhaps near zero .

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Nature Unbound VIII – Modern global warming

by Javier

Summary: Modern Global Warming has been taking place for the past 300 years. It is the last of several multi-century warming periods that have happened during the Neoglacial cooling of the past 3000 years. Analysis of Holocene climate cycles shows that the period 1600-2100 AD should be a period of warming. The evidence suggests that Modern Global Warming is within Holocene variability, but the cryosphere displays a non-cyclical retreat that appears to have undone thousands of years of Neoglacial ice advance. The last 70 out of 300 years of Modern Global Warming are characterized by human-caused, extremely unusual, rapidly increasing CO2 levels. In stark contrast with this rapidly accelerating anthropogenic forcing, global temperature and sea level appear to have continued their rising trend with no perceptible evidence of added acceleration. The evidence supports a higher sensitivity to CO2 in the cryosphere, suggesting a negative feedback by H2O, that prevents CO2 from having the same effect elsewhere.

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