Thursday, July 21, 2016

he Antarctic peninsula is COOLING

Laughs all round with this one. They want to say that this finding has no implications for the globe as a whole.  Since Antarctica has 96% of the world's glacial ice, it surely has BIG implications for the scare about rising sea levels. Zwally has shown that Antractica as a whole is gaining mass so put the two findings together and it undermines the very thing that Warmists have made central to their cries of doom!  Unless there is significant warming and melting in Antarctica, there is no doom! The way it's going, we are headed for a sea-level FALL!

And their explanation for the cooling is pathetic.  They say it's caused by the ozone hole shrinking.  But it isn't. The hole was at its largest in October.  Not October 10 years ago or even October 5 years ago.  It was October LAST YEAR.  The ban on our best refrigerant gases has clearly had no effect whatever.

Their other explanation is: "Temperatures have decreased as a consequence of a greater frequency of cold, east-to-southeasterly winds". But why?  Why did these winds spring up promptly at the beginning of the 21st century. If they have been going for around 20 years now, why did they not spring up earlier?  What has  changed?  It's essentially a non-explanation, which is why they have defaulted to "natural variability" as an explanation.  But in that case why is the slight warming of the 20th century not natural variability too?  They're getting into some very deep water there.

When big icebergs break off Arctica or Antarctica that is regularly said to be evidence of global warming.  I wonder why "natural variability" is not invoked on those occasions?  It seems to be a case of Warmists trying to have their cake and eat it too.

But whatever the cause, we have in the work below yet another example of global warming prophecy failing.  I append the extract from the underlying journal article

The Antarctic is one part of the world you might have thought would be affected by global warming.  But for the last two decades, the Antarctic peninsula – the tip of the continent nearest to South America - has not got any warmer, scientists have found.

Research stations on the peninsula show that a while temperatures rose rapidly since the 1950s, the temperature has stayed steady and even declined since the late 1990s.

A new study has recorded an ozone increase in the icy region, suggesting the agreement signed nearly three decades ago to limit the use of substances responsible for ozone depletion, is having a positive effect.

As well as creating an identifying ozone increase, it’s slowing the rate of ozone depletion in the stratosphere - Earth's second major atmospheric layer.

Part of the answer why the Antarctic peninsula has not got any warmer in the past two to three decades is because more cold south-easterly and easterly winds are blowing towards the area from the Weddell Sea.

A further reason is because the hole in the ozone layer – caused by gases in aerosols called CFCs – is beginning to heal up – helping to shield Antarctica from solar radiation.

The hole has started to close since the polluting CFCs have been banned.

The scientists behind the finding are keen to stress that the ‘pause’ in Antarctic warming does not mean that global warming worldwide has come to a stop.

They say the six research stations on the peninsula cover only 1 per cent of the total continent of Antarctica.

Glaciers are still retreating – and ice shelves are still collapsing in the region.

They also note that temperatures are still warmer than at the beginning of the century.

Reporting this week in the journal Nature researchers from British Antarctic Survey (BAS) said changing wind patterns may also be ‘temporarily masking’ the warming influence of greenhouse gases.

The authors also note that the ‘pause’ in warming coincides with the controversial ‘global warming hiatus’ or slowdown, which claims that global temperatures started to slowdown from 1996 from rising 0.14°C per decade up to 1996 and rising to 0.07°C per decade afterwards.

But the authors argue that the pause in the Antarctic is ‘independent of the global warming hiatus’.

Lead author, Professor John Turner of British Antarctic Survey says: ‘The Antarctic Peninsula is one of the most challenging places on Earth on which to identify the causes of decade-to-decade temperature changes.’

They said that the peninsula ‘shows large natural variations which can overwhelm the signals of human-induced global warming’.

He added: ‘The ozone hole, sea-ice and westerly winds have been significant in influencing regional climate change in recent years.

‘Even in a generally warming world, over the next couple of decades, temperatures in this region may go up or down, but our models predict that in the longer term greenhouse gases will lead to an increase in temperatures by the end of the 21st Century.’

Antarctic Peninsula temperatures increased by up to 0.5°C per decade until the 1950s when they stopped rising, the researchers said.

The research team analysed ice cores taken from drilling into the soil – which allow scientists to calculate the temperature at the time the ice was laid down.

They found that the warming of the peninsula ‘was not unprecedented’ over the past 2,000 years.

Recently, they found that warming started in the 1920s, and revealed ‘periods of warming and cooling over the last several centuries that were comparable to those observed in the post-1950s instrumental record.’

The authors said the findings ‘highlights the large natural variability of temperatures in this region of Antarctica that has influenced more recent climate changes.’

Dr Robert Mulvaney, is a leading ice core researcher at British Antarctic Survey, said: ‘Meteorological observations from the Antarctic Peninsula research stations only cover the last 60 years or so. If we are to get a better idea of the long-term trend we need to look back in time.

‘The ice core record helps us see how the climate evolves over the longer term. We can also look at the levels of carbon dioxide and other chemicals that were in the atmosphere and compare them with observations from today.’

‘Climate model simulations predict that if greenhouse gas concentrations continue to increase at currently projected rates their warming effect will dominate over natural variability (and the cooling effect associated with recovering ozone levels) and there will be a warming of several degrees across the region by the end of this century.’


Absence of 21st century warming on Antarctic Peninsula consistent with natural variability

John Turner et al.

Since the 1950s, research stations on the Antarctic Peninsula have recorded some of the largest increases in near-surface air temperature in the Southern Hemisphere1. This warming has contributed to the regional retreat of glaciers2, disintegration of floating ice shelves3 and a ‘greening’ through the expansion in range of various flora4. Several interlinked processes have been suggested as contributing to the warming, including stratospheric ozone depletion5, local sea-ice loss6, an increase in westerly winds5, 7, and changes in the strength and location of low–high-latitude atmospheric teleconnections8, 9. Here we use a stacked temperature record to show an absence of regional warming since the late 1990s. The annual mean temperature has decreased at a statistically significant rate, with the most rapid cooling during the Austral summer. Temperatures have decreased as a consequence of a greater frequency of cold, east-to-southeasterly winds, resulting from more cyclonic conditions in the northern Weddell Sea associated with a strengthening mid-latitude jet. These circulation changes have also increased the advection of sea ice towards the east coast of the peninsula, amplifying their effects. Our findings cover only 1% of the Antarctic continent and emphasize that decadal temperature changes in this region are not primarily associated with the drivers of global temperature change but, rather, reflect the extreme natural internal variability of the regional atmospheric circulation.

Nature 535, 411–415 (21 July 2016) doi:10.1038/nature18645

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