Report spurs call for urgent cuts in greenhouse gas emissions

GREENHOUSE gas emissions must be cut urgently if the worst effects of climate change on the world’s oceans and the Antarctic are to be avoided, Prof Christina Hulbe warns.

She was commenting on a special report on the ocean and cryosphere, released by the Intergovernmental Panel on Climate Change this week.

Prof Hulbe, the dean of the University of Otago School of Surveying, said the report had called for urgent cuts.

Some more positive outcomes could be achieved if New Zealand and other nations took this step.

This was also what her children and Dunedin school pupils were seeking in their School Strike 4 Climate action in the city today, she said.

Prof Hulbe’s research includes modelling scenarios which could lead to the collapse of the West Antarctic Ice Shelf.

The Special Report on the Ocean and Cryosphere showed the climate change drumbeat was not in the distance — ‘‘it’s here and it’s loud’’.

Some consequences were unavoidable, but ‘‘some of the most serious outcomes can still be avoided’’.

The best available computer models suggested the threshold for large, irreversible change was nearby — somewhere between 1.5degC and 2degC global mean warming, she said.

Prof Cliff Law, of Niwa and the University of Otago, said that the IPCC report was a call for action —‘‘one we need to prioritise if we value our oceans’’.

The report showed oceans had provided ‘‘an amazing buffer’’ against climate change.

By absorbing 20%30% of the carbon dioxide we had released and more than ‘‘an incredible 90%’’ of the extra heat retained in the global climate system, the oceans had prevented Earth overheating.

However, there had been changes in ocean currents, chemistry and ecosystems, and these were projected to worsen, he said.