Ocean warming on the rise

Lead author Dr Catia Domingues (far right) with co-authors of the Nature paper -- (left to right) Jeff Dunn, Susan Wijffels, Neil White, Argo engineer Vito Dirita and Paul Barker... Click here for more information.

Increased scientific confidence that ocean observations are accurately reflecting rising global temperatures is central to new Australian research published today in the journal, Nature.

The team of Australian and US climate researchers found the world's oceans warmed and rose at a rate 50 per cent faster in the last four decades of the 20th century than documented in the 2007 Intergovernmental Panel on Climate Change Report (IPCC AR4).

The research gives significantly greater credibility to the way climate models simulate the degree of warming in the world's oceans – a key indicator of sea-level rise and climate change.

The results were added to other recent estimates of contributions to sea-level rise, including glaciers, ice caps, Greenland and Antarctic ice sheets, and thermal expansion changes in the deep ocean. The sum of all contributions is more consistent with observed sea-level rise than earlier studies.

"For the first time, we can provide a reasonable account of the processes causing the rate of global sea-level rise over the past four decades – a puzzle that has led to a lot of scientific discussion since the 2001 IPCC report but with no significant advances until now," says CSIRO Wealth from Oceans National Research Flagship scientist, Dr Catia Domingues, from the Centre for Australian Weather and Climate Research.

"Following the review of millions of ocean measurements, predominantly from expendable instruments probing the upper 700 metres of the ocean, we were able to more accurately estimate upper-ocean warming, and the related thermal expansion and sea-level rise.