Global warming: Australian scientists say strong winds in Pacific behind pause in rising temperatures

Updated

Scientists say stronger than normal winds in the Pacific are the explanation for a pause in global warming, which has long been a point of contention raised by climate change sceptics.

Over the past 15 years the rate of global warming has slowed - and more recently almost stalled.

Sceptics say the slowdown suggests warming is not as bad as first thought, while most climate scientists say it is just a natural climate variability.

Now an Australian-led team of researchers has found strong winds in the Pacific Ocean are most likely to be behind the hiatus.

The study found that the winds were churning the Pacific like a washing machine, bringing the deeper colder water to the surface and pushing the warmer water below.

But University of New South Wales (UNSW) researcher Matthew England, part of the team which carried out the research, said he did not expect the effect to last.

"The phase we're in of accelerated trade winds particularly lasts a couple of decades," Professor England said.

"We're about 12 to 13 years in to the most accelerated part of the wind field.

"It's important to point out there's a cycle we expect to reverse and when they do reverse back to their normal levels, we'd expect global warming to kick in and start to rise."

Professor England rejects the argument from sceptics that the slowdown suggests global warming is not as bad as first thought and that the climate models are not working.

"We want the community to have confidence in the climate models," he said.

We want the community to have confidence in the climate models. They are very good but in this instance the wind acceleration has been... much stronger than what the models projected." Professor Matthew England

"They are very good but in this instance the wind acceleration has been that strong and that much stronger than what the models projected."

Scientists used satellite measurements and an array of floats in the Pacific to observe two-decades worth of temperature and current information.

The CSIRO's Steve Rintoul said understanding the oceans was the key to understanding climate change.

"What's not commonly understood is that when we talk about global warming, we mean ocean warming," Dr Rintoul said.

"Over the last 50 years, 90 per cent of the extra heat that's been stored by the earth is found in the ocean.

"So if we want to track how climate is changing, we need to be looking in the ocean to understand it."

The research is published in the journal Nature Climate Change.

Topics: climate-change, environment, earth-sciences, science-and-technology, pacific, university-of-new-south-wales-2052

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