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To: Brumar89 who wrote (77514)	6/19/2017 9:02:59 AM
From: Eric	Read Replies (2) \| Respond to of 86356

Warm Waters in West Antarctica A recent paper in Reviews of Geophysics describes the atmospheric and oceanic processes that are causing ice loss in the Antarctic. Thwaites Glacier flows out into the Amundsen Sea Embayment where it floats on the seawater. The underside is being melted by relatively warm water. Credit: NASABy John Turner and Hilmar Gudmundsson on 16 June 2017 The vast Antarctic ice sheet contains about 30 million cubic kilometers of ice, which is 90% of the Earth’s freshwater ice. If it were all to melt, it would increase sea level by about 70 meters. Fortunately, surface temperatures across most of the continent stay well below freezing all year round so there is virtually no ice loss through surface melt. Instead, most of the ice loss is through iceberg calving and ocean-induced melting from the under-side of ice shelves. One area that scientists are keeping a close eye on is the Amundsen Sea Embayment to the west of the Antarctic Peninsula. Here the ice is being melted from below by warm ocean waters at a greater rate than ice is added through snow accumulation, and this region is currently contributing about a tenth of current global sea level rise. A review article recently published in Reviews of Geophysics examined the complex atmospheric and oceanic factors that control the delivery of warm waters to the sub-ice region of West Antarctica and considered the potential for ice loss in the future. The editors asked two of the authors to give an overview of scientific research in this area. What are marine-based ice sheets and why are they important? Most of the ice across the East Antarctic rests on rock that is above sea level and is therefore relatively stable. However, the West Antarctic Ice Sheet is a marine-based ice sheet where much of the ice sits on bedrock that is below sea level. This makes it vulnerable to relatively warm waters melting the ice from below, especially in the areas where the ice floats on the ocean as ice shelves. The melting, retreat and thinning of the glaciers around the Amundsen Sea Embayment over recent decades is of great concern because the ice shelves buttress the ice in the interior of West Antarctica and there is a fear that loss of the ice shelves will accelerate the loss of ice in the future. What controls the loss of ice from West Antarctica? Delivery of warm water to below the ice shelves of the Amundsen Sea Embayment is strongly influenced by the winds over the Southern Ocean just to the north of the region and therefore the weather systems in this area. Storm activity here is more variable than anywhere else on Earth as a result of being affected by tropical climate variability, such as the El Niño Southern Oscillation, and the Antarctic ozone hole. Melting of the ice is therefore very variable on a year to year basis. How is data collected about ice, ocean and atmosphere characteristics around Antarctica? The Amundsen Sea Embayment is a very remote part of the Antarctic but summer field parties have visited this area to make surface measurements and drill down through the ice shelves to make measurements of the ocean conditions below. Satellite pictures have also been extremely important for monitoring the retreat of the ice, and photographs taken from aircraft have provided data since the 1940s. Recently, autonomous vehicles have been used to make measurements of temperature and water mass characteristics under the ice. How can modeling contribute to a better understanding of these interactions? Coupled atmosphere–ocean models are the main tool we have for predicting the future evolution of the Earth’s climate system. However, these models don’t currently include ocean currents penetrating under the ice shelves, nor the motion of ice streams. So, at present, a range of high resolution, limited area models of different parts of the system are run separately, such as models of individual ice streams. The eventual goal is to develop coupled atmosphere–ocean–ice modelling systems that can reproduce observed past changes and provide guidance on how the West Antarctic Ice Sheet will change in the future. What additional data or modeling efforts are needed? We need more information on the conditions under the ice shelves, especially near the grounding line where the ice starts to float on the ocean. Such data could be obtained from autonomous vehicles and drilling through the ice shelves to install sub-ice instrumentation. We need longer records of broadscale atmospheric and ocean conditions for the period before in-situ observations were made. Data from ice and ocean sediment cores can help in this regard. Modelling the complex interactions between the atmosphere, ocean and ice is currently not possible and we need to advance the modelling of selected elements of the Antarctic coastal environment, such as transport of warm waters under the ice shelves and ocean–ice coupling before we can develop models of the entire system. What is the future of the West Antarctic Ice Sheet? This is the biggest and most important question of all. The recent ice loss around the Amundsen Sea Embayment could signal the start of an unstable phase of glacier retreat in the region that will result in the collapse of much of the West Antarctic Ice Sheet, such as has happened a number of times in the past. On the other hand, the current retreat could be short-lived and the system may find a new stable state. Without improved observations of the ongoing retreat and better models of the whole system either scenario is possible. —John Turner, British Antarctic Survey; email: jtu@bas.ac.uk; and Hilmar Gudmundsson, British Antarctic Survey, eos.org

To: Brumar89 who wrote (77514)	6/20/2017 4:34:24 PM
From: Brumar89	1 Recommendation Recommended By Jon Koplik Respond to of 86356

That 14.8C degrees current global temperature again A correspondent has updated me on the above issue. He points out that the 14.8C GAT referred to is also the Annual Average for 2016. 14.84C is shown at the NOAA Annual Summary here. They show .94 anomaly + 13.9 average, which is 14.84. This compares with HIGHER temperatures reported for 1997 and 1998 NOAA say that their 1997 and 1998 averages were wrong and that they have subsequently been revised downwards. They say: "Please note: the estimate for the baseline global temperature used in this study differed, and was warmer than, the baseline estimate (Jones et al., 1999) used currently. This report has been superseded by subsequent analyses. However, as with all climate monitoring reports, it is left online as it was written at the time." That is mightily convenient. It becomes amazingly convenient when one notes that the original GAT for 1997 in the report was 16.92C -- ie over 2.0C warmer than 2016. Over the last 20 years they have lowered the 1998 temperature by 2.4C, and they currently say records are being broken by a measly tenth or hundredth of a degree. Clearly, the average global temperature is at best an unreliable and wild guess of no worth for policy or any other purposes. On the original NOAA figures, the earth has COOLED by 2 degrees since 1997/1998 -- JR --------------------------------------------------------------- I've gone to the source sites and copied this: ... The average global temperature across land and ocean surface areas for 2016 was 0.94°C (1.69°F) above the 20th century average of 13.9°C (57.0°F) ............ The 1901-2000 average combined land and ocean annual temperature is 13.9°C (56.9°F), the annually averaged land temperature for the same period is 8.5°C (47.3°F), and the long-term annually averaged sea surface temperature is 16.1°C (60.9°F). https://www.ncdc.noaa.gov/sotc/global/201613 ------------------------------------------------------ The whole claim the earth is rapidly warming is crap. The experts said the avg earth temp was 15.0C for about a hundred years. Now they say 2016 was 14.84C, which they claim is a new record high. The only reason to say that's a new record high is they've lowered the historical temps of the past century. And now the temp of 2016 which is almost exactly what they used to say was the avg for 1896-1988 is high ONLY because of the lowering adjustments. Now let's look back at what NOAA said the avg temp was in 1997: ncdc.noaa.gov The global average temperature of 62.45 degrees Fahrenheit for 1997 was the warmest year on record ... 62.45F = 16.92C So how can 2016's 14.84C be a record high when they said back in 1997, that that year was 16.92C? It can't.