- Joined
- Jan 28, 2013
- Messages
- 94,823
- Reaction score
- 28,342
- Location
- Williamsburg, Virginia
- Gender
- Male
- Political Leaning
- Independent
This was presented by a regular contributor to Judith Curry's Climate, Etc. blog. It is refreshingly unpolemical.
Nature Unbound VIII – Modern global warming
Posted on February 26, 2018 | 12 comments
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.
Continue reading →
Conclusions
1) Modern Global Warming is one of several multi-centennial warming periods that have taken place in the last 3000 years.
2) Holocene climate cycles project that the period 1600-2100 AD should be a period of warming.
3) A consilience of evidence supports that Modern Global Warming is within Holocene variability.
4) Modern Global Warming displays an unusual non-cyclical cryosphere retreat. The contraction appears to have undone most of the Neoglacial advance.
5) The last quarter (70 yr) of Modern Global Warming is characterized by extremely unusual and fast rising, very high CO2 levels, higher than at any time during the Late Pleistocene. This increase in CO2 is human caused.
6) The increase in temperatures over the past 120 years shows no perceptible acceleration, and contrasts with the accelerating CO2 forcing.
7) Sea level has been increasing for the past 200 years, and its modest acceleration for over a century shows no perceptible response for the last decades to strongly accelerating anthropogenic forcing.
8) The evidence supports a higher sensitivity to increased CO2 in the cryosphere, which is driving unusual melting and a small long-term sea level rise acceleration. The rest of the planet shows a lower sensitivity, indicating a negative feedback by H2O, that prevents CO2 from having the same effect elsewhere.
Nature Unbound VIII – Modern global warming
Posted on February 26, 2018 | 12 comments
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.
Continue reading →
Conclusions
1) Modern Global Warming is one of several multi-centennial warming periods that have taken place in the last 3000 years.
2) Holocene climate cycles project that the period 1600-2100 AD should be a period of warming.
3) A consilience of evidence supports that Modern Global Warming is within Holocene variability.
4) Modern Global Warming displays an unusual non-cyclical cryosphere retreat. The contraction appears to have undone most of the Neoglacial advance.
5) The last quarter (70 yr) of Modern Global Warming is characterized by extremely unusual and fast rising, very high CO2 levels, higher than at any time during the Late Pleistocene. This increase in CO2 is human caused.
6) The increase in temperatures over the past 120 years shows no perceptible acceleration, and contrasts with the accelerating CO2 forcing.
7) Sea level has been increasing for the past 200 years, and its modest acceleration for over a century shows no perceptible response for the last decades to strongly accelerating anthropogenic forcing.
8) The evidence supports a higher sensitivity to increased CO2 in the cryosphere, which is driving unusual melting and a small long-term sea level rise acceleration. The rest of the planet shows a lower sensitivity, indicating a negative feedback by H2O, that prevents CO2 from having the same effect elsewhere.