World’s oceans are heating up at a quickening pace: study

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TAMPA, Jan 11, 2019 (BSS/AFP) – The world’s oceans are heating up at an
accelerating pace as global warming threatens a diverse range of marine life
and a major food supply for the planet, researchers said Thursday.

The findings in the US journal Science, led by the Chinese Academy of
Sciences, debunk previous reports that suggested a so-called pause in global
warming in recent years.

The latest technology shows no such hiatus ever existed, raising new
concerns about the pace of climate change and its effect on the planet’s main
buffer — the oceans.

“Ocean heating is a very important indicator of climate change, and we have
robust evidence that it is warming more rapidly than we thought,” said co-
author Zeke Hausfather, a graduate student in the Energy and Resources Group
at the University of California, Berkeley.

About 93 percent of excess heat — trapped around the Earth by greenhouse
gases that come from the burning of fossil fuels — accumulates in the
world’s oceans.

The latest report relied on four studies, published between 2014 and 2017,
that gave more precise estimates of past trends in ocean heat, allowing
scientists to update past research and hone predictions for the future.

A key factor in the more accurate numbers is an ocean monitoring fleet
called Argo, which includes nearly 4,000 floating robots that “drift
throughout the world’s oceans, every few days diving to a depth of 2,000
meters (yards) and measuring the ocean’s temperature, pH, salinity and other
bits of information as they rise back up,” said the report.

Argo “has provided consistent and widespread data on ocean heat content
since the mid-2000s,” it said.

The new analysis shows warming in the oceans is on pace with measurements
of rising air temperature.

And if nothing is done to reduce greenhouse gases, “models predict that the
temperature of the top 2,000 meters of the world’s oceans will rise 0.78
degrees Celsius by the end of the century,” it said.

The thermal expansion — water swelling as it warms — would raise sea
level 12 inches (30 centimeters), above any sea level rise from melting
glaciers and ice sheets.

“While 2018 will be the fourth warmest year on record on the surface, it
will most certainly be the warmest year on record in the oceans, as was 2017
and 2016 before that,” Hausfather said.

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