Science with Jonathan Webb: Ocean temperature is warming faster than we thought

Great Barrier Reef in the Coral Sea off the coast of Queensland Australia 2018

In fact, the Earth's oceans are warming 40% faster than that United Nations panel predicted, according to new analysis published Thursday in the journal Science.

Researchers have now combined findings from multiple studies to show there has been a consistent warming trend even during the so-called hiatus, a 15-year period at the beginning of this century when land temperatures seemed to hold.

We could see many more weather-related problems if the ocean continues to warm at this accelerated pace, especially if there is no human intervention to manage climate change, experts say. "As 2017 was the warmest year, and 2016 was the warmest year", Zeke Hausfather, an author of the study and energy systems analyst at the independent climate research group Berkeley Earth, told The New York Times . According to the Coupled Model Intercomparison Project 5 (CMIP5) models, the temperature of the top 2,000 meters of global oceans will increase by 0.78 degrees Celsius by 2099.

Prior to Argo, ocean temperature data was sparse at best, relying on devices called expendable bathythermographs that sank to the depths only once, transmitting data until settling into watery graves. According to a report by the Chinese Academy of Sciences, in the journal "Science".

The newly available data show stronger ocean warming since 1960 than earlier reported by the IPCC's Fifth Assessment Report in 2013.

The increasing rate of ocean warming "is simply a signature of increasing greenhouse gases in the atmosphere", Cheng said.

The thermal expansion - water swelling as it warms - would raise sea level 30 centimeters, above any sea level rise from melting glaciers and ice sheets.

"The global warming signal is a lot easier to detect if it is changing in the oceans than on the surface".

The study authors say the warming is happening because of climate change created by such human activities as the burning of fossil fuels. And, unlike surface temperatures, ocean temperatures are not affected by year-to-year variations caused by climate events like El Nino or volcanic eruptions.

Another study report from the European Union's Copernicus Climate Change Service had revealed that 2018 was the fourth warmest year, in terms of global surface temperatures, in records dating back to the 19th century. If no actions are taken ("business as usual"), the upper ocean above 2000 meters will warm by 2020 ZetaJoules by 2081-2100, which is about 6 times larger than the total ocean warming during the past 60 years. In addition, the warming of sea water leads to a further destruction of the coral reefs and reduces the oxygen content in the oceans.

Through the data collected, scientists have documented increases in rainfall intensity and more powerful storms such as hurricanes Harvey in 2017 and Florence in 2018.