5 Antarctic facts for climate change sceptics
Five indisputable truths for sceptics who say that MV Akademik Shokalskiy's 'failed' mission disproves scientific theories on ice
To most people the prolonged stranding of the MV Akademik Shokalskiy in thick pack ice off the coast of Antarctica is an unfortunate incident that provided passengers with rather static scenery for their Christmas and New Year celebrations.
But to some climate change contrarians, repeated attempts to free the vessel from the ice are proof that the theory of climate change is flawed or, at best, exaggerated. After all, a warming planet has no ice at all, right?
In Sydney's , Roger Franklin dispensed with analysis of ice extent, the cyrosphere and the like to get to the heart of the matter - expedition leader Chris Turney is a "warmist" whose understanding of Antarctica amounts to little more than it gets "really, really cold".
newspaper darkly intoned that the stranding was a "hard lesson for those who persistently exaggerate the impact of global warming".
Helpfully, the newspaper said that researchers aboard the Akademik Shokalskiy have suffered an "embarrassing failure" in their mission, which apparently was not to follow in the footsteps of explorer Douglas Mawson and build on his scientific observations but to prove beyond doubt that climate change is real.
ABC science broadcaster Adam Spencer took to Twitter to lament that "you'd fail a year 8 science test if you presented the misunderstandings" contained in 's editorial. To help clear up the confusion, here are some basic Antarctic facts.
The Antarctic is an enormous frozen continent that covers about a fifth of the southern hemisphere. It is the driest, windiest continent on Earth, covered by ice that can reach 4 kilometres deep.
A new world record for a low temperature was set in December when a NASA satellite clocked a reading of minus 93.3 degrees Celsius on the east Antarctic plateau.
Surrounding the vast glacial, or land-based, ice is sea ice, which contracts and expands depending on the season. This is an important distinction, which we will get to shortly.
Essentially, the Antarctic is a continent of ice surrounded by cold water.
The Arctic is a semi-enclosed ocean, almost completely surrounded by land. Steadily warming land and sea temperatures have had a visible impact on the Arctic, with its extent reaching record lows in recent years.
The loss of ice in Antarctica does not appear to be as dramatic and it is even increasing in places, leading some to believe this means global warming is not occurring.
"When people talk about an increase in ice they are actually talking about sea ice, which is completely different from continental ice. Warmer oceans help melt the ice and make it thinner, which has been observed in the Arctic. In Antarctica it's more complicated. It is losing continental ice while sea ice has been increasing by about 1 per cent a decade," said Tony Press, chief executive of the Antarctic Climate and Ecosystems Co-operative Research Centre based at the University of Tasmania.
Studies have found Antarctica has lost about 100 billion tonnes of continental ice a year since 1993, causing the global sea level to rise by about 0.2mm a year.
The latest climate report from the Intergovernmental Panel on Climate Change, released last year, said there was "high confidence" that the Antarctic ice sheet had been losing ice during the past two decades.
But this loss, caused by warming oceans, has been countered by an increase in ice in the Ross Sea region. This is the result of a range of factors, including climate change.
Contrary to some of the more outlandish claims made by climate change deniers, the ship was not suddenly enveloped by ice due to rapidly plummeting temperatures.
It was pinned by ice from the Mertz glacier, a well-established ice formation.
"In the last few years the ice near where the ship is bogged has become less accessible," Press said. "This will eventually break up and move away, depending on wind patterns, storms, tidal activity and ambient temperatures. These are variable, local conditions."
The Australian Antarctic Division has been collecting data on ice flow, thickness and other such things in east Antarctica for more than 50 years.
Despite this, the organisation admits there are still gaps in scientific understanding of the Antarctic, mainly around the dynamics of ice sheets. This understanding will be improved by rigorous analysis of gathered evidence.
It's unlikely a single ship getting stuck in ice will cause a major deviation in researchers' findings.
