Sea Ice Expansion in the Southern Hemisphere: Another Reason to Abandon Global Warming Policy

Observed (blue) and model-forecast (red) Antarctic sea-ice extent published by Shu et al. (2015)
shows a large and growing discrepancy, but for unknown reasons, their illustration ends in 2005
.
A paper published in Journal of Climate 30: 2251-2267 titled Positive trend in the Antarctic sea ice cover and associated changes in surface temperature: Comiso et al: (link)

Abstract
The Antarctic sea ice extent has been slowly increasing contrary to expected trends due to global warming and results from coupled climate models. After a record high extent in 2012 the extent was even higher in 2014 when the magnitude exceeded 20 × 106 km2 for the first time during the satellite era. The positive trend is confirmed with newly reprocessed sea ice data that addressed inconsistency issues in the time series. The variability in sea ice extent and ice area was studied alongside surface ice temperature for the 34-yr period starting in 1981, and the results of the analysis show a strong correlation of −0.94 during the growth season and −0.86 during the melt season. The correlation coefficients are even stronger with a one-month lag in surface temperature at −0.96 during the growth season and −0.98 during the melt season, suggesting that the trend in sea ice cover is strongly influenced by the trend in surface temperature. The correlation with atmospheric circulation as represented by the southern annular mode (SAM) index appears to be relatively weak. A case study comparing the record high in 2014 with a relatively low ice extent in 2015 also shows strong sensitivity to changes in surface temperature. The results suggest that the positive trend is a consequence of the spatial variability of global trends in surface temperature and that the ability of current climate models to forecast sea ice trend can be improved through better performance in reproducing observed surface temperatures in the Antarctic region.

Craig Idso and Patrick Michaels, writing for Cato,

Global Science Report: Sea Ice Expansion in the Southern Hemisphere Is Real and Driven by Falling Temperatures

For those who utilize and trust in the scientific method, forming policy (especially multi-trillion dollar policies!) on the basis of what could or might happen in the future seems imprudent. Sound policy, in contrast, is best formulated when it is based upon repeated and verifiable observations that are consistent with the projections of climate models. As shown above, this does not appear to be the case with the vast ice field that surrounds Antarctica. 
According to the most recent report by the Intergovernmental Panel on Climate Change (IPCC), CO2-induced global warming will result in a considerable reduction in sea ice extent in the Southern Hemisphere. Specifically, the report predicts a multi-model average decrease of between 16 and 67 percent in the summer and 8 to 30 percent in the winter by the end of the century (IPCC, 2013). Given the fact that atmospheric CO2 concentrations have increased by 20 percent over the past four decades, evidence of sea ice decline should be evident in the observational data if such model predictions are correct. But are they? 
Thanks to a recent paper in the Journal of Climate by Josefino Comiso and colleagues, we now know what’s driving the increase in sea-ice down there. It’s—wait for it—cooling temperatures over the ocean surrounding Antarctica.

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