Sunday, September 14, 2014

New paper links Arctic sea ice extent to absorption of sunlight by clouds

A new paper published in the Journal of Geophysical Research Atmospheres finds Arctic sea ice concentrations at the low of each summer are related to absorption of sunlight by cloud cover at the top of the atmosphere in early summer, a phenomenon "not represented in most of current climate models."

According to the authors, 
"absorbed solar radiation at the top of the atmosphere in early summer (May–July) plays a precursory role in determining the Arctic sea ice concentration in late summer (August–October)"   
"this intimate delayed...relationship is not represented in most of current climate models. Rather, the models tend to over-emphasize internal sea ice processes in summer."
Alarmists focus on Arctic sea ice as the supposed canary in the coal mine for CAGW, but many papers have demonstrated natural variability is more likely responsible for the trends in Arctic sea ice than man-made CO2, including the natural Atlantic Multidecadal Oscillation, Atlantic Meridional Overturning Circulation [AMOC]wind  & storm activity, and long-term solar variability. This new paper suggests another way that natural variability controls Arctic sea ice extent via cloud cover, another possible solar amplification mechanism  via the cosmic ray theory of climate.

Alarmists ignore the unspeakable all-time record highs in Antarctic sea ice extent broken over each of the past three years, as do climate models, which laughably predicted the opposite of a decrease in Antarctic sea ice extent more so than Arctic sea ice. 

Alarmists also claim current Arctic sea ice changes are "unprecedented" while ignoring proxy data indicating Arctic sea ice was much less than present-day during the Holocene Climate Optimum ~6,000 years ago, Arctic temperatures were warmer than the present multiple times over past 1357 years, the Medieval Warming Period in the Arctic was warmer than the present, Alaskan glaciers are about the same size as during the Medieval Warm Period, etc., etc.



Connecting early summer cloud-controlled sunlight and late summer sea ice in the Arctic


Yong-Sang Choi, Baek-Min Kim, Sun-Kyong Hur, Seong-Joong Kim, Joo-Hong Kim, Chang-Hoi Ho

This study demonstrates that absorbed solar radiation (ASR) at the top of the atmosphere in early summer (May–July) plays a precursory role in determining the Arctic sea ice concentration (SIC) in late summer (August–October). The monthly ASR anomalies are obtained over the Arctic Ocean (65°N–90°N) from the Clouds and the Earth's Radiant Energy System during 2000–2013. The ASR 
[absorbed solar radiation] changes primarily with cloud variation. We found that the ASR [absorbed solar radiation] anomaly in early summer is significantly correlated with the SIC [Arctic sea ice concentration] anomaly in late summer (correlation coefficient, r ≈ −0.8 with a lag of 1 to 4 months). The region exhibiting high (low) ASR anomalies and low (high) SIC anomalies varies yearly. The possible reason is that the solar heat input to ice is most effectively affected by the cloud shielding effect under the maximum TOA solar radiation in June and amplified by the ice-albedo feedback. This intimate delayed ASR-SIC relationship is not represented in most of current climate models. Rather, the models tend to over-emphasize internal sea ice processes in summer.

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