Energy and
Environment
Temperatures
in the Arctic are skyrocketing — for the third time this winter
By Chelsea Harvey
February 10
Image obtained
using Climate Reanalyzer, Climate Change Institute, University of
Maine.
While much of the
Northeast was forced to batten down the hatches this week against
strong winds, heavy snow and other icy conditions, the usually frigid
Arctic experienced the opposite — a period of unseasonably mild
weather and high temperatures, for at least the third time this
winter.
A powerful
low-pressure storm system in the northern Atlantic has helped carry
warm air up to the frozen north this week, sending temperatures in
the Arctic soaring. Data from the Danish Meteorological Institute
suggests that, as of Thursday, temperatures in the area above 80
degrees north latitude were already more than 20 degrees warmer than
the average temperature for this time of year. As the image above
from Climate Reanalyzer shows, the most unusually warm region is
right over the North Pole.
It’s at least the
third such extreme winter-warming event for the Arctic this season —
temperatures skyrocketed on two occasions in November and December as
well. Similar incidents also occurred in December of 2015 and 2014.
Scientists believe
that a number of different factors are feeding into these warming
events, including the steady march of climate change and interactions
between the air and Arctic sea ice, which global warming is melting a
little more each year. And a good low-pressure system, like the one
that barreled through this week, can help to jump-start these kinds
of sudden warming events by carrying a large amount of warm air up to
the North Pole all at once.
The presence of the
storm itself isn’t exactly unusual, according to atmospheric
physics expert Kent Moore of the University of Toronto. Each year,
there are some storms that roll through the northern Atlantic. What’s
uncommon is just how far north some of them have been making it
lately.
“There’s these
extratropical cyclones that appear to be tracking farther north than
they usually do, and these low-pressure systems are bringing the heat
up into the polar region,” he said. It’s unclear why this
happens, he added. But when it does, temperatures can vault up above
zero degrees, or in extreme cases, sometimes even above freezing.
In a recent paper
published in December, Moore notes that these types of anomalous
warming events have been recorded since the 1950s — but they
usually only occur once or twice a decade. Scientists believe that
factors related to climate change may now be making it easier for
weather systems like this week’s storm to carry warm air into the
Arctic.
Changes in Arctic
sea ice extent are one major issue. As a result of global warming,
temperatures in the Arctic are rising at about twice the global
average rate, and one of the consequences is a reduction in Arctic
sea ice. These changes are most obvious in the warm summer months,
when sea ice is at a minimum anyway — but lately, scientists have
been observing record lows for the frozen winter months as well, a
time of year when the ice is actually expanding. But where it is
missing, those parts of the ocean become warmer.
“As that sea ice
moves northward, there’s a huge reservoir of heat over the north
Atlantic,” Moore said. “As we lose the sea ice, it allows
essentially this reservoir of warmth to move closer to the pole.”
When this happens,
storm systems may be able to carry heat farther north than usual. In
fact, earlier this week, scientists at the National Snow and Ice Data
Center announced that sea ice remained at record low daily extents
through the month of January. Sea ice extent for the month averaged
5.17 million square miles, the lowest January extent on record.
(National Snow and
Ice Data Center)
Some scientists also
believe that rapid warming in the Arctic has helped bring about
changes in certain atmospheric patterns — causing the jet stream’s
flow to become more “wavy,” for instance — in ways that can
affect weather systems in the north Atlantic.
Moore noted that
weather-induced warming events in the Arctic tend to be short-lived,
meaning this week’s event — like similar others in the past —
will probably not persist for more than a few days. But he added that
an increase in the frequency of temperature extremes at the North
Pole is just another indicator of climate change’s disproportionate
effect on the Arctic.
“There’s more
and more evidence that the Arctic, especially, is warming quite
dramatically and that we should expect to see more of these events,”
he said. “I think it’s just more evidence that the climate is, in
fact, changing.”
Could
a £400bn plan to refreeze the Arctic before the ice melts really
work?
Temperatures
are now so high at the north pole that scientists are contemplating
radical schemes to avoid catastrophe
Robin McKie Observer
science editor
Sunday 12 February
2017 00.05 GMT
Physicist Steven
Desch has come up with a novel solution to the problems that now
beset the Arctic. He and a team of colleagues from Arizona State
University want to replenish the region’s shrinking sea ice – by
building 10 million wind-powered pumps over the Arctic ice cap. In
winter, these would be used to pump water to the surface of the ice
where it would freeze, thickening the cap.
The pumps could add
an extra metre of sea ice to the Arctic’s current layer, Desch
argues. The current cap rarely exceeds 2-3 metres in thickness and is
being eroded constantly as the planet succumbs to climate change.
“Thicker ice would
mean longer-lasting ice. In turn, that would mean the danger of all
sea ice disappearing from the Arctic in summer would be reduced
significantly,” Desch told the Observer.
Desch and his team
have put forward the scheme in a paper that has just been published
in Earth’s Future, the journal of the American Geophysical Union,
and have worked out a price tag for the project: $500bn (£400bn).
It is an astonishing
sum. However, it is the kind of outlay that may become necessary if
we want to halt the calamity that faces the Arctic, says Desch, who,
like many other scientists, has become alarmed at temperature change
in the region. They say that it is now warming twice as fast as their
climate models predicted only a few years ago and argue that the 2015
Paris agreement to limit global warming will be insufficient to
prevent the region’s sea ice disappearing completely in summer,
possibly by 2030.
“Our only strategy
at present seems to be to tell people to stop burning fossil fuels,”
says Desch. “It’s a good idea but it is going to need a lot more
than that to stop the Arctic’s sea ice from disappearing.”
The loss of the
Arctic’s summer sea ice cover would disrupt life in the region,
endanger many of its species, from Arctic cod to polar bears, and
destroy a pristine habitat. It would also trigger further warming of
the planet by removing ice that reflects solar radiation back into
space, disrupt weather patterns across the northern hemisphere and
melt permafrost, releasing more carbon gases into the atmosphere.
Hence Desch’s
scheme to use wind pumps to bring water that is insulated from the
bitter Arctic cold to its icy surface, where it will freeze and
thicken the ice cap. Nor is the physicist alone in his Arctic
scheming: other projects to halt sea-ice loss include one to
artificially whiten the Arctic by scattering light-coloured aerosol
particles over it to reflect solar radiation back into space, and
another to spray sea water into the atmosphere above the region to
create clouds that would also reflect sunlight away from the surface.
All the projects are
highly imaginative – and extremely costly. The fact that they are
even being considered reveals just how desperately worried
researchers have become about the Arctic. “The situation is causing
grave concern,” says Professor Julienne Stroeve, of University
College London. “It is now much more dire than even our worst case
scenarios originally suggested.’
Last November, when
sea ice should have begun thickening and spreading over the Arctic as
winter set in, the region warmed up. Temperatures should have
plummeted to -25C but reached several degrees above freezing instead.
“It’s been about 20C warmer than normal over most of the Arctic
Ocean. This is unprecedented,” research professor Jennifer Francis
of Rutgers University told the Guardian in November. “These
temperatures are literally off the charts for where they should be at
this time of year. It is pretty shocking. The Arctic has been
breaking records all year. It is exciting but also scary.”
Nor have things got
better in the intervening months. Figures issued by the US National
Snow and Ice Data Center (NSIDC), in Boulder, Colorado, last week
revealed that in January the Arctic’s sea ice covered 13.38 million
sq km, the lowest January extent in the 38 years since satellites
began surveying the region. That figure is 260,000 sq km below the
level for January last year, which was the previous lowest extent for
that month, and a worrying 1.26 million sq km below the long-term
average for January.
In fact, sea ice
growth stalled during the second week of January – in the heart of
the Arctic winter – while the ice cap actually retreated within the
Kara and Barents seas, and within the Sea of Okhotsk. Similarly, the
Svalbard archipelago, normally shrouded in ice, has remained
relatively free because of the inflow of warm Atlantic water along
the western part of the island chain. Although there has been some
recovery, sea ice remains well below all previous record lows.
The area covered by
Arctic sea ice at least four years old has decreased from 1,860,000
sq km in September 1984 to 110,000 sq km in September 2016. In this
visualisation, the age of the ice is indicated by shades ranging from
blue-gray for the youngest ice to white for the oldest. Photograph:
Scientific Visualization Studio/Nasa
This paucity of sea
ice bodes ill for the Arctic’s summer months when cover
traditionally drops to its lower annual level, and could plunge to a
record minimum this year. Most scientists expect that, at current
emission rates, the Arctic will be reliably free of sea ice in summer
by 2030.
By “free” they
mean there will be less than 1m sq km of sea ice left in the Arctic,
most of it packed into remote bays and channels, while the central
Arctic Ocean over the north pole will be completely open. And by
“reliably”, scientists mean there will have been five consecutive
years with less than 1m sq km of ice by the year 2050. The first
single ice-free year will come much earlier than this, however.
And when that
happens, the consequences are likely to be severe for the human and
animal inhabitants of the region. An ice-free Arctic will be wide
open to commercial exploitation, for example. Already, mining, oil
and tourism companies have revealed plans to begin operations –
schemes that could put severe strain on indigenous communities’ way
of life in the region.
Equally worrying is
the likely impact on wildlife, says Stroeve. “Juvenile Arctic cod
like to hang out under the sea ice. Polar bears hunt on sea ice, and
seals give birth on it. We have no idea what will happen when that
lot disappears. In addition, there is the problem of increasing
numbers of warm spells during which rain falls instead of snow. That
rain then freezes on the ground and forms a hard coating that
prevents reindeer and caribou from finding food under the snow.”
Nor would the rest
of the world be isolated. With less ice to reflect solar radiation
back into space, the dark ocean waters of the high latitudes will
warm and the Arctic will heat up even further.
“If you warm the
Arctic you decrease the temperature difference between the poles and
the mid-latitudes, and that affects the polar vortex, the winds that
blow between the mid latitudes and the high latitudes,” says Henry
Burgess, head of the Arctic office of the UK Natural Environment
Research Council.
“Normally this
process tends to keep the cold in the high north and milder air in
mid-latitudes but there is an increasing risk this will be disrupted
as the temperature differential gets weaker. We may get more and more
long, cold spells spilling down from the Arctic, longer and slower
periods of Atlantic storms and equally warmer periods in the Arctic.
What happens up there touches us all. It is hard to believe you can
take away several million sq km of ice a few thousand kilometres to
the north and not expect there will be an impact on weather patterns
here in the UK.”
For her part,
Stroeve puts it more bleakly: “We are carrying out a blind
experiment on our planet whose outcome is almost impossible to
guess.”
This point is backed
by Desch. “Sea ice is disappearing from the Arctic – rapidly. The
sorts of options we are proposing need to be researched and discussed
now. If we are provocative and get people to think about this, that
is good.
“The question is:
do I think our project would work? Yes. I am confident it would. But
we do need to put a realistic cost on these things. We cannot keep on
just telling people, ‘Stop driving your car or it’s the end of
the world’. We have to give them alternative options, though
equally we need to price them.”
THE BIG SHRINK
The Arctic ice cap
reaches its maximum extent every March and then, over the next six
months, dwindles. The trough is reached around mid-September at the
end of the melting season. The ice growth cycle then restarts.
However, the extent of regrowth began slackening towards the end of
the last century. According to meteorologists, the Arctic’s ice
cover at its minimum is now decreasing by 13% every decade – a
direct consequence of heating triggered by increased levels of carbon
dioxide in the atmosphere.
Climate change
deniers claim this loss is matched by gains in sea ice around the
Antarctic. It is not. Antarctic ice fluctuations are slight compared
with the Arctic’s plummeting coverage and if you combine the
changes at both poles, you find more than a million sq km of ice has
been lost globally in 30 years.
Humans
causing climate to change 170 times faster than natural forces
Researchers
behind ‘Anthropocene equation’ say impact of people’s intense
activity on Earth far exceeds that of natural events spread across
millennia
Melissa Davey
@MelissaLDavey
Sunday 12 February
2017 06.44 GMT
For the first time,
researchers have developed a mathematical equation to describe the
impact of human activity on the earth, finding people are causing the
climate to change 170 times faster than natural forces.
The equation was
developed in conjunction with Professor Will Steffen, a climate
change expert and researcher at the Australian National University,
and was published in the journal The Anthropocene Review.
The authors of the
paper wrote that for the past 4.5bn years astronomical and
geophysical factors have been the dominating influences on the Earth
system. The Earth system is defined by the researchers as the
biosphere, including interactions and feedbacks with the atmosphere,
hydrosphere, cryosphere and upper lithosphere.
Climate change:
Australia falling behind rest of world on emissions cuts, says report
Read more
But over the past
six decades human forces “have driven exceptionally rapid rates of
change in the Earth system,” the authors wrote, giving rise to a
period known as the Anthropocene.
“Human activities
now rival the great forces of nature in driving changes to the Earth
system,” the paper said.
Steffen and his
co-researcher, Owen Gaffney, from the Stockholm Resilience Centre,
came up with an “Anthropocene Equation” to determine the impact
of this period of intense human activity on the earth.
Explaining the
equation in New Scientist, Gaffney said they developed it “by
homing in on the rate of change of Earth’s life support system: the
atmosphere, oceans, forests and wetlands, waterways and ice sheets
and fabulous diversity of life”.
“For four billion
years the rate of change of the Earth system has been a complex
function of astronomical and geophysical forces plus internal
dynamics: Earth’s orbit around the sun, gravitational interactions
with other planets, the sun’s heat output, colliding continents,
volcanoes and evolution, among others,” he wrote.
“In the equation,
astronomical and geophysical forces tend to zero because of their
slow nature or rarity, as do internal dynamics, for now. All these
forces still exert pressure, but currently on orders of magnitude
less than human impact.”
According to Steffen
these forces have driven a rate of change of 0.01 degrees Celsius per
century.
Greenhouse gas
emissions caused by humans over the past 45 years, on the other hand,
“have increased the rate of temperature rise to 1.7 degrees Celsius
per century, dwarfing the natural background rate,” he said.
This represented a
change to the climate that was 170 times faster than natural forces.
“We are not saying
the astronomical forces of our solar system or geological processes
have disappeared, but in terms of their impact in such a short period
of time they are now negligible compared with our own influence,”
Steffen said.
“Crystallising
this evidence in the form of a simple equation gives the current
situation a clarity that the wealth of data often dilutes.
“What we do is
give a very specific number to show how humans are affecting the
earth over a short timeframe. It shows that while other forces
operate over millions of years, we as humans are having an impact at
the same strength as the many of these other forces, but in the
timeframe of just a couple of centuries.
“The human
magnitude of climate change looks more like a meteorite strike than a
gradual change.”
Gaffney and Steffen
wrote that while the Earth system had proven resilient, achieving
millions of years of relative stability due to the complex
interactions between the Earth’s core and the biosphere, human
societies would be unlikely to fare so well.
Failure to reduce
anthropological climate change could “trigger societal collapse”,
their research concluded.
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