Did
the authors of this travel to the Arctic or even look up from their
computer screens out the window?
Keep
this article in mind over the coming weeks.
Perhaps it will take another 32 years for the remaining 0.5 meters of ice to disappear?
Could
the Arctic have ice-free summers in our lifetime?
2
April, 2018
One
of the big questions about global warming is when — or if — the
Arctic will be ice-free each summer.
A
study
published Monday said if the world warms 7.2 degrees this century,
the Arctic will likely have a three-month, ice-free period each
summer by 2050. It would be a worst-case scenario never seen in
recorded human history.
By
the end of the century, the ice-free summer could jump to five months
a year, the study said.
The
shrinking sea ice is caused by rising global temperatures that stem
from the burning of fossil fuels, such as oil, gas and coal,
according to the National Snow and Ice Data Center.
Sea
ice floats on the ocean and has an annual cycle of freezing in the
winter and melting each summer.
Why
does it matter? Arctic ice not only is important to polar bears and
other wildlife, but it also helps regulate the planet’s
temperature. Recent studies also said that Arctic sea ice — and the
lack of it — can wreak havoc with weather patterns as far away as
the United States.
A
visible sign of climate change is the drastic decline in Arctic sea
ice. Since 1979, the minimum annual area of sea ice in the Arctic has
dropped by about 40%, as measured each September.
More:
Arctic sea ice nears all-time record wintertime low
This
study, which used computer models to estimate future warming and
melting, outlined a range of possibilities for Arctic sea ice,
depending on how much Earth's temperature rises.
For
example, if the world warms only 2.7 degrees, which was the goal set
by the Paris Climate Agreement, the probability of ice-free summers
drops dramatically.
With
a rise of 2.7 degrees, "half of the time we stay within our
current summer sea ice regime," said Alexandra Jahn, author of
the study and an assistant professor at the University of Colorado.
"If we reach 3.6 degrees of warming, the summer sea ice area
will always be below what we have experienced in recent decades.”
The
study was published in the peer-reviewed British journal Nature
Climate Change.
A
separate article in the journal said that while the difference
between a rise of 2.7 degrees and 3.6 degrees is clear, exact
probabilities about the future of summertime Arctic ice should be
viewed with caution:
"The
sensitivity of sea ice to global warming in the real world is highly
uncertain, which makes it difficult to assess whether sea ice is lost
at the correct rate in climate models,” wrote James Screen, a
climate scientist at the University of Exeter.
No comments:
Post a Comment
Note: only a member of this blog may post a comment.