New Zealand and Chile are seeking US$10 million ($13.8 million) in United Nations funding to conduct the first comprehensive study of the effects of global warming on Southern Hemisphere glaciers.
The two countries have applied to a fund run by the United Nations Environment Programme to study glaciers in New Zealand, South America and Antarctica.
The project follows Chilean-American research showing that glaciers flowing north from the eastern Pacific part of Antarctica - called "West Antarctica" because it is west of the Atlantic - are thinning dramatically at rates averaging one metre a year.
The director of Chile's Centre of Scientific Studies, Dr Claudio Teitelboim, who passed through Auckland yesterday on his way back from Antarctica, said big icebergs breaking off the edge of the ice shelf were "unblocking the plug" that was holding in the ice behind, allowing glaciers to flow out to sea more quickly.
"We believe West Antarctica is unstable and therefore eventually large pieces of ice can fall into the sea," he said.
"The Antarctic Peninsula [due south of South America] might become, within the lifetime of our children, an archipelago instead of a peninsula."
The Chilean-US studies suggest glaciers melting in West Antarctica are raising the global sea level by about 0.2mm a year, a bit more than a tenth of the total increase in sea level of around 1.8mm.
Melting of glaciers in the rest of the world account for about half the total sea level rise, with the rest due to other factors such as warmer water expanding.
But Dr Teitelboim warned:
"Once the instability acquires enough magnitude so glaciers break off upstream, the whole platform will fall into the sea. Then it's not just a few millimetres.
"If it's only a few millimetres a year for thousands of years, we would be in good shape. But that's not how instabilities work. Suddenly they become truly unstable."
Canterbury University glaciologist Luke Copland, who is collaborating with the Chileans on the proposed United Nations study, said parts of Antarctica were getting colder at the same time as others were getting warmer.
Ironically, New Zealand's Scott Base and the US McMurdo Station may have to close this winter because a large iceberg has blocked the mouth of the Ross Sea, probably preventing the annual visit by a US icebreaker with supplies.
"We are not seeing that dramatic thinning on the Ross Sea side of West Antarctica. If anything, things are icing up more than melting.
" If the climate warms, two things will happen. One, the ice will melt, but two, it's very, very cold in Antarctica, so if you warm up the atmosphere from minus 20C to minus 15C, it will cause more evaporation off the oceans and therefore more snowfall.
"So climate warming may cause an increase in the size of Antarctica, not a decrease, straight away. That is what may be happening on the Ross ice shelf."
He said there had been many studies of Northern Hemisphere glaciers, but there had never been any coordinated monitoring of the main Southern Hemisphere glaciers in Antarctica, the Andes and New Zealand's Southern Alps.
Dr Teitelboim is on his way home from the first overland Latin American scientific expedition to the South Pole, a 1084km convoy to measure the rate of ice thinning.
At one point, the convoy could not find a way around a crevasse and decided to drive across it at speed.
"While we were crossing it, it opened up," Dr Teitelboim said.
"That was a bit scary. Fortunately, the width was less than the length of the module, so we went at full speed over it."
Dr Teitelboim's nose was frostbitten when the convoy reached the US base at the South Pole.
"My nose was the only place exposed, for about 20 minutes, but it was minus 50C. I didn't feel anything, but it was black."
The damage is now reduced to peeling, and Dr Teitelboim will keep his nose. |
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