"Oct.
31, 2013 — A recent
slowdown in global warming has led some skeptics to renew their claims that
industrial carbon emissions are not causing a century-long rise in Earth's
surface temperatures. But rather than letting humans off the hook, a new study
in the leading journal Science adds support to the idea that the oceans
are taking up some of the excess heat, at least for the moment. In a
reconstruction of Pacific Ocean temperatures in the last 10,000 years,
researchers have found that its middle depths have warmed 15 times faster in
the last 60 years than they did during apparent natural warming cycles in the
previous 10,000."
Buoys that are
placed all over the ocean measure ocean heat. Instruments from ships are also
lowered to record temperatures. Another method that is used is the analysis of
the chemistry of ancient marine life. Over the last 10,000 years the climate
has been pretty stable. In the last 60 years though, from the surface of the
Earth to 2,200 feet, the climate has increased 0.18 degrees Celsius, which
might seem small but this rate of increase is 15 times fast than any period
throughout the last 10,000 years.
In the most
recent report that was released in September, the UN’s Intergovernmental Panel
on Climate Change (IPCC) shared that there has been a slowdown in global
warming. Each decade from 1950-1990, the temperature increased by 1/5th of
a degree Fahrenheit. After 1998, a very hot year, the warming rate lowered by
half. The IPCC says that it’s because “the pause to natural climate
fluctuations caused by volcanic eruptions, changes in solar intensity, and the
movement of heat through the ocean”. The IPCC believes that the ocean has
collected much of the green house gas that humans have put into the atmosphere
but findings in Science think of the long-term consequences of this. Yair
Rosenthal, a Rutgers University scientist, says that the oceans may be storing
more of the effects of human emission than we think. He says the ocean’s
absorbing the effects may slow down climate change but not stop it.
Buoys that are
placed all over the ocean measure ocean heat. Instruments from ships are also
lowered to record temperatures. Another method that is used is the analysis of
the chemistry of ancient marine life. Over the last 10,000 years the climate
has been pretty stable. In the last 60 years though, from the surface of the
Earth to 2,200 feet, the climate has increased 0.18 degrees Celsius, which
might seem small but this rate of increase is 15 times fast than any period
throughout the last 10,000 years.
One
explanation for the recent slow down in climate warming is because there might
be a La Niña-like cooling in the eastern Pacific waters. Climate modelers from
Scripps Institution of Oceanography demonstrated that la Niña cooling seems to
slow down during the winter in the northern hemisphere but it allows for the
waters to really become warm during the summer. “When the La Niña cycle
switches, and the Pacific reverts to a warmer than usual El Niño phase, global
temperatures may likely shoot up again, along with the rate of warming.” Global
temperatures do not steadily raise, instead Kevin Trenberth, a climate scientist
at the National Center for Atmospheric Research, describes it as walking up a
staircase for 10 years and then you have a jump in which things are never the
same like before. Drew Shindell, a climate scientist who works at Columbia’s
Earth Institute and the NASA Goddard Institute for Space Studies, believes that
looking at surface temperature may not be as useful as looking at stored energy
by the climate system.
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