Chinese researchers find the OPPOSITE of what global warming theory predicts -- in a study of Antarctic ice 1978–2016

They found lots of ups and downs in sea ice extent but a significant trend towards MORE ice.

They were however mostly interested in what caused the fluctuations, in particular the very low ice cover in February 2011 and the big bounceback the year after.  They attributed it to variations in cloud cover. No mention of CO2

And they found that clouds had a COOLING effect, which is the exact opposite of what global warming theory says.  Warmists say that a warmer climate will produce more clouds -- which it well may do -- but then go on to say that the clouds will produce warming

They also note that trends in the Arctic are very different,  which rules out any global process being involved.  But by definition can you have ANY global process that does not include the poles?


The Contributions of Winter Cloud Anomalies in 2011 to the Summer Sea‐Ice Rebound in 2012 in the Antarctic

Yunhe Wang et al.

Abstract

Antarctic sea‐ice extent exhibits a modest positive trend in the period of near four decades. In recent years, the fluctuation in Antarctic sea ice has been strengthened, including a decrease toward the lowest sea‐ice extent in February 2011 for the period of 1978–2016 and a strong rebound in the summer of 2012. The sea‐ice recovery mainly occurs in the Weddell Sea, Bellingshausen Sea, Amundsen Sea, southern Ross Sea, and the eastern Somov Sea. This study offers a new mechanism for this summertime sea‐ice rebound. We demonstrate that cloud‐fraction anomalies in winter 2011 contributed to the positive Antarctic sea‐ice anomaly in summer 2012.

The results show that the negative cloud‐fraction anomalies in winter 2011 related to the large‐scale atmospheric circulation resulted in a substantial negative surface‐radiation budget, which cooled the surface and promoted more sea‐ice growth. The sea‐ice growth anomalies due to the negative cloud forcing propagated by sea‐ice motion vectors from September 2011 to January 2012. The distribution of the sea‐ice anomalies corresponded well with the sea‐ice concentration anomalies in February 2012 in the Weddell Sea and eastern Somov Sea. Thus, negative cloud‐fraction anomalies in winter can play a vital role in the following summer sea‐ice distribution.

Introduction

Contrasting to Arctic sea ice, which has decreased in all seasons and at nearly all locations (Comiso et al.,2017; Liu, Lin, Kong, et al., 2016; Liu, Lin, Wang, et al., 2016; Wang et al., 2018), the sea‐ice extent (SIE)around Antarctica has displayed a marked seasonal cycle (Polvani & Smith, 2013) and a modest, but statis-tically significant, positive trend since 1979 (Hobbs et al., 2016; Holland, 2014; Simmonds, 2015). Also, different regional trend distributions exist in Antarctic sea‐ice with rapid sea‐ice loss in the Amundsen Sea and Bellingshausen Sea, while significant and moderate ice gain in the Ross Sea and Weddell Sea, respectively. Large cancellations from different sectors have resulted in a net positive trend in the Antarctic totalSIE (Parkinson & Cavalieri, 2008).However, the causes of the Antarctic sea‐ice expansion remain a matter of debate, which could be caused by anthropogenic and natural factors. Some mechanisms have been suggested. Liu and Curry (2010) suggested that increased precipitation in the warming climate is an attributable factor for the current Antarctic sea‐icegrowth. In an ice‐ocean modeling study, Zhang (2014) suggested that strengthened westerlies increasesea‐ice volume by producing more ridged ice, which leads to sea ice more resilient to melting. There wasa hypothesis that increased surface freshwater from the Antarctic continent and enhanced snowfall promotesea‐ice expansion by stabilizing the upper water column (Rignot et al., 2013), which increases upper‐oceanstratification and suppresses oceanic heat transport (Bintanja et al., 2013; Liu & Curry, 2010). In addition,the dipole pattern of the Pacific sector, combined with increasing sea ice in the Ross Sea and decreasingice in the Bellingshausen Sea, has been ascribed to strengthening the Amundsen Sea low (Clem & Fogt,2015; Fogt et al., 2012; Meehl et al., 2016; Raphael et al., 2016; Turner et al., 2016). Moreover, these sea‐ice trend patterns around Antarctica have been attributed to interdecadal variability (Fan et al., 2014;Gagné et al., 2015), sea‐surface temperature warming in the tropical Pacific (Clem & Fogt, 2015), andatmospheric intrinsic variability in the Antarctic (Turner et al., 2016

Journal of Geophysical Research: Atmospheres 2018, Volume 124, Issue 6


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