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                Climate Change Rate May Be Faster Than Expected

   by George Putic

   The latest findings by a group of prominent scientists say our planet
   has not seen its surface warm up so much, in such a short period,
   during the past 66 million years and the impact will come much quicker
   and with much worse consequences than previously thought.
   According to a study published in 2006 in the online journal Science,
   the last sudden rise of CO2 in the Earth's atmosphere happened 55
   million years ago and lasted for about 170,000 years. The global
   temperature then increased about five degrees Celsius, causing profound
   changes in the planet's ecology, including mass extinctions.
   In a new 52-page report, published Tuesday in the scientific journal
   [1]Atmospheric Chemistry and Physics, 19 scientists say we are
   releasing CO2 in the atmosphere much faster than 55 million years ago,
   and that even two degrees Celsius rise of the average temperature will
   have catastrophic effects on the planet's climate.
   Authors warn of collapsing ice sheets, violent mega storms and giant
   waves.
   The leader of the study, former NASA scientist James Hansen, says we
   may already have passed the point of no return and future generations
   will bear the dire consequences.
   When Hansen issued the first warning last summer, some journalists and
   fellow scientists criticized it as lacking enough evidence.  But he has
   since been joined, in a peer review, by many other prominent scientists
   who revised the paper and made it less dramatic.  But serious concerns
   remain.
   Combining evidence about ancient climate changes, modern observations
   and results of computer modeling, the authors conclude that rapid
   melting of Greenland and Antarctica ice will cause not only a rise in
   sea levels, but also many other climate changes.
   Specifically, they point to a phenomenon called `stratification,' which
   means formation of cold water pools on the ocean's surface, caused by
   melting of the ice sheets.  The warm water trapped below will continue
   to melt the bottom of the ice sheets, contributing to rapid sea level
   rise.  Evidence of stratification has already been observed off the
   Greenland's southern coast.
   According to the study, the changes will lead to a growing temperature
   differential between northern and equatorial regions, that in turn will
   cause intense cyclones and storms with gigantic waves.
   The findings cited in the study are supported with other research, such
   as that done by the U.S. National Oceanic and Atmospheric
   Administration.
   Some reviewers have been praising the report as a "masterwork of
   scholarly synthesis", while others say it is still not certain that it
   will "match what will happen in the real world."
   However, as one of the reviewers, Penn State glaciologist Richard
   Alley, said, "the paper reminds us that large and rapid changes [of the
   climate] are possible.  We just don't know how much and how likely."

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   [2]http://www.voanews.com/content/climate-change-rate-may-be-faster-tha
   n-expected/3251205.html

References

   1. http://www.atmos-chem-phys.net/16/3761/2016/acp-16-3761-2016-discussion.html
   2. http://www.voanews.com/content/climate-change-rate-may-be-faster-than-expected/3251205.html