Category Archives: Attribution

Will advances in groundwater science force a paradigm shift in sea level rise attribution?

by Jim Steele

 A better accounting of natural groundwater discharge is needed to constrain the range of contributions to sea level rise. The greater the contribution from groundwater discharge, the smaller the adjustments used to amplify contributions from meltwater and thermal expansion.

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The Rise and Fall of Central England Temperatures: Part II

by Tony Brown

This article examines the continued cooling of CET this century

  • Looks at a similar scenario of regional cooling in America
  • Examines CET related urbanisation issues, and the current Met office allowances for this
  • Notes the centuries long general warming of our climate.
  • Notes considerable English seasonal variability over the centuries
  • Examines the key component parts of the weather that affect the British Isles
  • Queries whether wind direction, strength and longevity are major factors in shaping our climate over the centuries.

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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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Nature Unbound VII – Climate change mechanisms

by Javier

Climate variations that alter the angular momentum of the atmosphere modify the speed of the Earth’s rotation, which affects the length of day (LOD). Alterations in LOD integrate different climate-affecting phenomena, and can anticipate turning points in climate.

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Sea level rise acceleration (or not): Part I – Introduction

by Judith Curry

Introduction and context for a new Climate Etc. series on sea level rise.

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Manufacturing consensus: the early history of the IPCC

by Judith Curry

Short summary: scientists sought political relevance and allowed policy makers to put a big thumb on the scale of the scientific assessment of the attribution of climate change.

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Nature Unbound VI – Centennial to millennial solar cycles

by Javier

Summary: Holocene climate has been affected in different periods by several centennial to millennial solar cycles. The ~ 1000-year Eddy solar cycle seems to have dominated Holocene climate variability between 11,500-4,000 years BP, and in the last two millennia, where it defines the Roman, Medieval, and Modern warm periods. The ~ 208-year de Vries solar cycle displays strong modulation by the ~ 2400-year Bray solar cycle, both in its cosmogenic isotope signature and in its climatic effects. The Centennial, and Pentadecadal solar cycles are observable in the last 400-year sunspot record, and they are responsible for the present extended solar minimum that started in 2008.

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