OK...who is the "denier" here?
To answer your question,
consult your closest mirror ....
OK...who is the "denier" here?
A rare phenomenon causing "the strongest Antarctic warming on record" is set to deliver more pain to dought-stricken Australia, scientists said Friday.
The unusual event, known as "sudden stratospheric warming", started in the last week of August when the atmosphere above Antarctica began heating rapidly, scientists at Australia's Bureau of Meteorology said in a report.
"The Bureau of Meteorology is predicting the strongest Antarctic warming on record, likely to exceed the previous record of September 2002," it said.
The upper atmosphere above the South Pole has heated up from close to minus 70 to about minus 25 degrees Celsius, bureau climatologist Andrew Watkins told AFP.
"It has leapt up more than 40 degrees warmer than normal in the course of three weeks," he said.
Watkins said the uncommon occurrence was not believed to be linked to global warming.
The occurrence is triggered by a mix of "disturbances" in weather patterns closer to the ground, he added.
Sudden stratospheric warming is common in the northern hemisphere but has only been recorded on one other occasion, in 2002, in the southern hemisphere.
The rapid warming slows down westerly winds spinning in the upper atmosphere above the South Pole until they move to the surface.
The winds track northwards until they are over Australia, blowing eastwards across the dry centre to New South Wales and Queensland states, which are currently struggling through one of the driest periods on record.
"You start getting more winds from central Australia, from the desert and less winds from the ocean, so they tend to have drier, warmer conditions in New South Wales and Southern Queensland," Watkins said.
The impacts of the Antarctic event in Australia will start to arrive in the coming weeks, and be particularly felt in October before the weather pattern is expected to break down in December or January.
The east of Australia has been battling hundreds of bushfires in recent weeks, in an unusually early start to the season.
High‐spatial resolution surface mass balance (SMB) over the West Antarctic Ice Sheet (WAIS) spanning 1800–2010 is reconstructed by means of ice core records combined with the outputs of the European Centre for Medium‐Range Weather Forecasts “Interim” reanalysis (ERA‐Interim) and the latest polar version of the Regional Atmospheric Climate Model (RACMO2.3p2). The reconstruction reveals a significant negative trend (−1.9 ± 2.2 Gt/year·per decade) in the SMB over the entire WAIS during the nineteenth century, but a statistically significant positive trend of 5.4 ± 2.9 Gt/year·per decade between 1900 and 2010, in contrast to insignificant WAIS SMB changes during the twentieth century reported earlier. At regional scales, the Antarctic Peninsula and western WAIS show opposite SMB trends, with different signs in the nineteenth and twentieth centuries. The annual resolution reconstruction allows us to examine the relationships between SMB and large‐scale atmospheric oscillations. Although SMB over the Antarctic Peninsula and western WAIS correlates significantly with the Southern Annular Mode due to the influence of the Amundsen Sea Low, and El Niño/Southern Oscillation during 1800–2010, the significant correlations are temporally unstable, associated with the phase of Southern Annular Mode, El Niño/Southern Oscillation and the Pacific decadal oscillation. In addition, the two climate modes seem to contribute little to variability in SMB over the whole WAIS on decadal‐centennial time scales. This new reconstruction also serves to identify unreliable precipitation trends in ERA‐Interim and thus has potential for assessing the skill of other reanalyses or climate models to capture precipitation trends and variability.
The seaward flow of ice from grounded ice sheets to the ocean is often resisted by the buttressing effect of floating ice shelves. These ice shelves risk collapsing as the climate warms, potentially exposing tall cliff faces. Some suggest ice cliffs taller than ~90 m could collapse under their own weight, exposing taller cliffs further to the interior of a thickening ice sheet, leading to runaway ice‐sheet retreat. This model, however, is based on studies of pre‐existing cliffs found at calving fronts. In this study, we consider the transient case, examining the processes by which an ice cliff forms as a buttressing ice shelf is removed. We show that the height at which a cliff collapses increases with the timescale of ice‐shelf removal. If the ice shelf is removed rapidly, deformation may be concentrated, forming vertical cracks and potentially leading to the collapse of small (e.g., 90‐m) cliffs. However, if we consider ice‐shelf collapse timescales longer than a few days (consistent with observations), deformation is distributed throughout the cliff, which flows viscously rather than collapsing. We expect including the effects of such ice‐shelf collapse timescales in future ice‐sheet models would mitigate runaway cliff collapse and reduce predicted ice‐sheet mass loss.
justinhinkle wrote:The average annual temperature ranges from about −10°C on the Antarctic coast to −60°C at the highest parts of the interior.
justinhinkle wrote:The average annual temperature ranges from about −10°C on the Antarctic coast to −60°C at the highest parts of the interior.
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