Darkening ice speeds up Greenland melt, new research suggests
Scientists
have noticed a curious thing happening as rising temperatures melt
the Greenland ice sheet. The ice that's left is getting darker,
making it more susceptible to further melting, according to new
research presented at the European Geosciences Union (EGU) conference
in Vienna.
Scientists
have identified three ways in which the gleaming white ice sheet is
getting darker, each contributing to the normally-reflective ice
sheet absorbing more of the sun's energy.
http://www.carbonbrief.org/blog/2015/04/darkening-ice-speeds-up-greenland-melt-new-research-suggests/
It’s
official: According to NOAA’s National
Climatic Data Center,
the first quarter of 2015 has set a new record, with the January
through March period coming in as the warmest such period on record
across the globe’s land and ocean surfaces.
The
month of March was also ranked warmest by NCDC in a record dating
back 136 years. The Japan Meteorological Agency concurs,
whereas NASA, which does its own independent analysis, ranked March
as third
warmest.
That’s a distinction without much of a difference since the
estimates of all three agencies are very close to each other
Darkening
of the Greenland Ice Sheet is projected to continue as a consequence
of continued climate warming, Dr. Marco Tedesco, a City College of
New York scientist, said at the European Geosciences Union (EGU)
General Assembly in Vienna today.
Tedesco
said that the projection is based on a model that only accounts for
the effects of warming on snow grain size and melting.
Measuring the depth of Arctic permafrost in Alaska. (Nick Bonzey via Flickr)
Three
sets of scientists in the same week have helped narrow the
uncertainties about how the natural world will respond to extra
carbon dioxide in the atmosphere caused by the burning of fossil
fuels.
Carbon
locked in the frozen earth will escape gradually as the Arctic
permafrost melts—but the scientists say the process could
accelerate.
As
greenhouse gas levels soar, and soils warm, and plant roots tap down
into the carbon stored there by centuries of ancient growth, they
will release potent chemicals that will accelerate microbial
attack—and speed up the release of carbon dioxide into the
atmosphere.
The
soil carbon cycle is one of the great headaches of climate science.
And the Arctic is the first place to look for answers about it, and
about how the Earth and oceans that store atmospheric carbon will
respond to global warming.
WHEN
IT COMES to doing research in the Amazon, Oliver Phillips says the
worst part is the sweat bees. Phillips, an ecologist from the
University of Leeds who has been working in the Amazon for 30 years,
says the bees don’t bite or sting or carry diseases, like many of
the rainforest’s other insects, but “they’re just all over
you.” The instant you start sweating—which is the instant you set
foot in the Amazon—they swarm your limbs, your nose, even your
eyes, ravenously feeding on the salt in your perspiration. “They
don’t do any damage except drive you crazy,” Phillips says......
Campaigner Anne-Line Thingnes Førsund looks out over Norway’s Førde Fjord, where the mining company Nordic Mining has been approved to dump 6m tonnes of waste a year. Photograph: Luka Tomac/Friends Of the Earth
Overpopulation, overconsumption – in pictures
Waves
of humanity
Sprawling
Mexico City rolls across the landscape, displacing every scrap of
natural habitat
‘If
our species had started with just two people at the time of the
earliest agricultural practices some 10,000 years ago, and increased
by one percent per year, today humanity would be a solid ball of
flesh many thousand light years in diameter, and expanding with a
radial velocity that, neglecting relativity, would be many times
faster than the speed of light.’ Gabor Zovanyi
Photograph:
Pablo Lopez Luz
To see more GO HERE
Report says 32 million people in Japan are exposed to radiation from the Fukushima nuclear disaster
Approximately
32 million people in Japan are affected by the radioactive fallout
from the nuclear disaster in Fukushima, according to the 2015
Fukushima Report now available from Green Cross. This includes people
who were exposed to radiation or other stress factors resulting from
the accident, and who are consequently at potential risk from both
long and short-term consequences.
The
2015 Fukushima Report is available for download in English
at http://www.greencross.ch/en/news-info-en/case-studies/fukushima-report.html.
As
with the Chernobyl nuclear accident, which impacted 10 million
people, Japan is expected to see increased cancer risk and
neuropsychological long-term health consequences. The stress-related
effects of evacuation and subsequent relocation are also of concern.
The evacuation involved a total of over 400,000 individuals, 160,000
of them from within 20km of Fukushima. The number of deaths from the
nuclear disaster attributed to stress, fatigue and the hardship of
living as evacuees is estimated to be around 1,700 so far.
Winter
is the prime season to see filaments of phytoplankton twist and curl
amid the Arabian Sea. On February 14, 2015, the Moderate
Resolution Imaging Spectroradiometer (MODIS)
on NASA’s Aqua satellite
acquired this image of the region’s winter blooms.
Why
winter? It turns out that in this part of the world, seasonal wind
patterns have a large effect on blooms. The winter monsoon brings a
reversal of wind direction—from southwesterly to
northeasterly—which stirs up nutrients that help phytoplankton
thrive.
Not
all phytoplankton are the same, however, and research has shown that
the composition of the communities in the Arabian Sea has shifted.
A study
published in 2008 reported
that an unusual abundance of Noctiluca
scintillans (also
called Nocticula
miliaris)
has started showing up in winter blooms over the last decade. The
newcomers have replaced the populations of diatoms that previously
prevailed.
Research
published in 2014 confirmed
that the outbreak of N.
scintillans in
the Arabian Sea is due to an unprecedented amount of oxygen-deficient
water near the sea’s surface. The exact reason for the influx is
still under investigation. What is apparent, however, is that N.
scintillans is
better equipped to handle the low-oxygen environment.
The
shift could have implications for the food web of the Arabian Sea. In
the past, fish ate the copepods that fed on the plentiful diatoms. In
contrast to the diatoms, N.
scintillans appears
to be too large for consumption by copepods and instead feed
creatures like jellyfish and salps. How this disruption to the
traditional food chain will impact regional fisheries remains to be
seen.
A
fast-moving brush fire threatened hundreds of homes in
drought-stricken southern California on Sunday, prompting mandatory
evacuations for local residents, authorities said.
The
Riverside County Fire Department said the fire erupted shortly after
6:00 pm (0100 GMT) on Saturday and had burned about 300 acres in an
area southeast of Los Angeles.
Some 200 homes were under evacuation orders and the American Red Cross opened an evacuation center for affected residents
Environmentalists
promised civil disobedience after Norway’s government approved a
controversial plan for a mining company to dump millions of tonnes of
waste into a fjord.
“This
is a fjord full of life – to smother it with toxins is insane,”
said Arnstein Vestre, president of Young Friends of the Earth Norway,
which has been part of protests against the plan. “We have 600
people ready to do civil disobedience actions, and we will not stop
until the fjord is safe,” he said.
Announcing
its approval of the project on Friday, industry minister Monica
Mæland said there would be strict environmental controls and
monitoring of waste matter.
North
Pacific mode linked to winter's weather extremes
'Snow
Wall' phenomenon in Japan (drone footage)
Drone
footage captured the stunning snow covered Tateyama Kurobe Alpine
route in the Murodo Plain, Sunday. The area is believed to receive
some of the heaviest snowfall on the planet, estimated to reach
around 66 feet (20.1 metres).
China now the world's biggest emitter: Local analysts say Australia is unlikely to reach its 5 per cent target by 2020 as the direct action policy stands. Photo: Reuters
The
world's biggest greenhouse gas emitters, including China and the US,
have questioned the credibility of Australia's climate change targets
and "direct action" policy in a list of queries to the
Abbott government.
In
the latest sign of diplomatic pressure over Canberra's stance on
global warming, China accused Australia of doing less to cut
emissions than it is demanding of other developed countries, and
asked it to explain why this was fair.
Beijing
also questioned whether the Abbott government's emissions reduction
fund – the centrepiece of its direct action policy, under which the
government will pay some emitters to make cuts – would be enough to
make up for the axed carbon price and meet Australia's commitment of
a minimum 5 per cent emissions cut below 2000 levels by 2020.
The
questions have been lodged with the United Nations for Australia to
answer in the lead-up to the December climate summit in Paris, where
the world is supposed to sign a global deal to combat climate
change.....
OTTAWA
- The latest emissions inventory from Environment Canada shows the
country's overall greenhouse gas output climbed 1.5 per cent between
2012 and 2013, continuing a slow, but steady, upward trend since the
global recession of 2009.
The
report, prepared by Environment Canada and submitted annually to the
United Nations Framework Convention on Climate Change, shows 726
megatonnes of emissions in 2013, still three per cent below Canada's
output in 2005.
However,
under the international Copenhagen Accord signed in 2009, Canada
committed to reduce its emissions by 17 per cent below 2005 levels by
2020 — and the trend is now firmly heading the wrong way.
In
a world-first study, scientists have transplanted kelp off the coast
of Tasmania to better understand the impact of climate change.
The
kelp, which grows from northern New South Wales around to Western
Australia, provides an ecosystem for hundreds of marine species.
Now
it is thinning and becoming patchy because of warming waters.
Divers
in Tasmania have spent months on the island's eastern sea floor
transplanting 500 kelp plants.
Shrinking
Antarctic has us skating on thin ice
Antarctic
ice is now melting faster than ever, raising sea levels. But the
degree of risk to our coastline and economy is still a big unknown
Matt King
SMH,
19
April, 2015
One
of the most troubling lines in the recent reports from the
Intergovernmental Panel on Climate Change was tucked away in a
footnote. It stated that, of their various future sea-level
scenarios, the estimate of the upper limit – a 1.1 metre rise by
2100 – was actually not the worst case. That is, the $226 billion
value of Australian roads, rail, commercial buildings and homes
spread over the coastal zone that may be underwater regularly by 2100
could be an underestimate. And they did not know by how much.
The
potential source of that extra water? A destabilised West Antarctic
Ice Sheet. The unknown that niggled at the authors was the
possibility that West Antarctica would do what observations and
theory say is possible – collapse, adding an extra five metres to
sea levels. Recent observations suggest irreversible retreat has now
commenced, and so the key question is not if, but how quickly? The
IPCC did not know and the science community still does not know
(guesses on timescales vary from 200 to 1000 years or more).
"We
now know that two huge areas of potential instability sit, almost
unstudied by anyone, within the Australian Antarctic Territory."
But
we are in a good position to begin to know. On Tuesday, April 21, I
will deliver a lecture at the Royal Society in London describing
remarkable progress in what we do know about Antarctica and its
contribution to sea-level change. Thanks to international efforts
coordinated by NASA and the European Space Agency we now know, for
the first time in history and with great confidence, that the
grounded ice of Antarctica is flowing into the ocean faster than
snowfall replenishes it, hence raising sea levels. That imbalance is
now 130 billion tonnes of ice each year.
And
we know that this change is happening faster and faster – in both
West Antarctica and Greenland. The big grounded ice sheets are now
contributing to sea-level rises at double the rate they were in the
1990s. These changes have been observed in different ways, using
different data, by different groups in different countries and the
result is not disputed.
This
success means scientists have never been better placed to address the
future of Antarctica and how it will affect our own coastal sea
levels. But their success, and the speed with which reliable
information can be put in the hands of policymakers, depends on all
the major Antarctic nations committing to long-term funded research
tied with long-term logistical infrastructure. Inconveniently, the
big unknowns are located away from our long-standing research
stations – indeed, they are in some of the most remote regions on
the planet.
It's
for this reason that the 20-year Australian Antarctic Strategic Plan
report, submitted in October last year, called for long-range
over-snow traversing capability and a funding cycle for both salaries
and logistics that matched our identified 10-year national Antarctic
strategic science goals. As the government considers that report, the
prestigious Academy of Sciences and scientists internationally have
urged us to retain our position as a major Antarctic scientific
nation by adopting the recommendations of that plan.
Australia
should not stand back and wait for other nations to do the work for
us. Our Antarctic claim, frozen under the Antarctic Treaty, is to 44
per cent of the continent. That claim consists of about 30 metres of
potential sea-level rise. Most of that sea level is safe for
millennia, but perhaps not all of it. Indeed, we now know that two
huge areas of potential instability sit, almost unstudied by anyone,
within the Australian Antarctic Territory.
Last
month an Australian and US collaboration revealed a significant chunk
of one of those regions can be added to West Antarctica as
potentially vulnerable to collapse – a further four metres of
sea-level rise now comes into play. Again, we don't know if this will
occur, and if so, how fast. We know the hazard, we just do not know
the degree of risk to us, our coastlines, our economy and our
lifestyles. And for the same reasons, we don't know the risk to our
regional neighbours, many of whom are not as well equipped to adapt
as we are.
The
currency of the Antarctic Treaty is not occupation of land but
science. We exercise influence over the future use of Antarctica by
studying the full extent of the Australian Antarctic Territory – in
the air, across the ground and at sea. For six decades or more
Australia has been a linchpin in the international collaboration that
have given us a first view of Antarctica. That science has led us to
a point where we know much about this iconic continent. But it is
what we do not know that should trouble us.
Matt
King is professor of polar geodesy and ARC Future Fellow at the
University of Tasmania. He is also the Royal Society of London's 2015
Kavli medallist and lecturer.
Researchers
at The University of Texas at Austin's Institute for Geophysics
(UTIG) in the Jackson School of Geosciences have discovered two
seafloor gateways that could allow warm ocean water to reach the base
of Totten Glacier, East Antarctica's largest and most rapidly
thinning glacier. The discovery, reported in the March 16 edition of
the journal Nature Geoscience, probably explains the glacier's
extreme thinning and raises concerns about how it will affect sea
level rise.
Totten
Glacier is East Antarctica's largest outlet of ice to the ocean and
has been thinning rapidly for many years. Although deep, warm water
has been observed seaward of the glacier, until now there was no
evidence that it could compromise coastal ice. The result is of
global importance because the ice flowing through Totten Glacier
alone is sufficient to raise global sea level by at least 11 feet,
equivalent to the contribution of the West Antarctic Ice Sheet if it
were to completely collapse.
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