Upload
adam-norfolk
View
218
Download
0
Tags:
Embed Size (px)
DESCRIPTION
Exercise using a 9 column grid.
Citation preview
Adam Norfolk9 Column Grid
46
DefrostsFreezerThe
Dramatic melting of sea ice due to global warming is having a major impact on the polar regionjohn vidal
47
environmentalist
With the melt happening at an
unprecedented rate of more
than 100,000 sq km a day, and
at least a week of further melt
expected before ice begins to
reform ahead of the northern
winter, satellites are expected to
confirm the record – currently
set in 2007 – within days.
“Unless something really unusual happens we
will see the record broken in the next few days.
It might happen this weekend, almost certainly
next week,” Julienne Stroeve, a scientist at the US
National Snow and Ice Data Centre (NSIDC) in
Boulder, Colorado, told the Guardian.
“In the last few days it has been losing 100,000
sq km a day, a record in itself for August. A storm
has spread the ice pack out, opening up water,
bringing up warmer water. Things are definitely
changing quickly.”
Because ice thickness, volume, extent and area are
all measured differently, it may be a week before
there is unanimous agreement among the world’s
cryologists (ice experts) that 2012 is a record
year. Four out of the nine daily sea ice extent and
area graphs kept by scientists in the US, Europe
and Asia suggest that records have already been
broken. “The whole energy balance of the Arctic
is changing. There’s more heat up there. There’s
been a change of climate and we are losing more
seasonal ice. The rate of ice loss is faster than the
models can capture [but] we can expect the Arctic
to be ice-free in summer by 2050,” said Stroeve.
Arctic sea ice is set to reach its lowest ever recorded extent as early as this weekend, in “dramatic changes” signalling that man-made global warming is having a major impact on the polar region.
48
“We can expect the Arctic
to be ice-free in summer by 2050 ”
“Only 15 years ago I didn’t expect to see such
dramatic changes – no one did. The ice-free
season is far longer now. Twenty years ago it
was about a month. Now it’s three months.
Temperatures last week in the Arctic were 14C,
which is pretty warm.”
Scientists at the Danish Meteorological Institute,
the Arctic Regional Ocean Observing System in
Norway and others in Japan have said the ice
is very close to its minimum recorded in 2007.
The University of Bremen, whose data does not
take into account ice along a 30km coastal zone,
says it sees ice extent below the all-time record
low of 4.33m sq km recorded in September 2007.
Ice volume in the Arctic has declined dramatically
over the past decade. The 2011 minimum
was more than 50% below that of 2005.
According to the Polar Science Centre at the
University of Washington it now stands at around
5,770 cubic kilometres, compared with 12,433 cu
km during the 2000s and 6,494 cu km in 2011.
The ice volume for 31 July 2012 was roughly
10% below the value for the same day in 2011.
A new study by UK scientists suggests that 900 cu
km of summer sea ice has disappeared from the
Arctic Ocean over the past year.
49
environmentalist
The consequences of losing the Arctic’s ice coverage for the summer
months are expected to be immense. If the white sea ice no longer
reflects sunlight back into space, the region can be expected to heat
up even more than at present. This could lead to an increase in
ocean temperatures with unknown effects on weather systems in
northern latitudes.
In a statement, a Greenpeace spokesman said: “The disappearing
Arctic still serves as a stark warning to us all. Data shows us that the
frozen north is teetering on the brink. The level of ice ‘has remained
far below average’ and appears to be getting thinner, leaving it more
vulnerable to future melting. The consequences of further rapid ice
loss at the top of the world are of profound importance to the whole
planet. This is not a warning we can afford to ignore.”
Longer ice-free summers are expected to open up the Arctic ocean
to oil and mining as well as to more trade. This year at least 20
vessels are expected to travel north of Russia between northern
Europe and the Bering straits. Last week a Chinese icebreaker made
the first voyage in the opposite direction.
“Every one of the 56,000 Inuits in Greenland have had to adapt to
the retreat of the ice,” said Carl-Christian Olsen, president of the
Inuit Circumpolar Council in Nuuk, Greenland. “The permafrost is
melting and this is jeopardising roads and buildings. The coastline
is changing, there is more erosion and storms, and there are fewer
mammals like polar bears. It means there can be more mining,
which is good for the economy, but it will have unpredictable effects
on social change”.
Research published in Nature today said that
warming in the Antarctic peninsula, where
temperatures have risen about 1.5C over the past
50 years, is “unusual” but not unprecedented
relative to natural variation. The research by
Robert Mulvaney of the British Antarctic Survey,
Cambridge, based on an ice-core record, showed
that the warming of the north-eastern Antarctic
peninsula began about 600 years ago.
The
coastline is
changing,
there is more
erosion
and storms,
and there
are fewer
mammals
like polar
bears.