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There is no way I can keep up with the stories. Here is a round-up of news from around the planet.
Melting
ice sheets release tons of methane into the atmosphere, study finds
3
January, 2019
The
Greenland Ice Sheet emits tons of methane according to a new study,
showing that subglacial biological activity impacts the atmosphere
far more than previously thought.
An
international team of researchers led by the University of Bristol
camped for three months next to the Greenland Ice Sheet, sampling the
meltwater that runs off a large catchment (> 600 km2) of the Ice
Sheet during the summer months.
As
reported in Nature,
using novel sensors to measure methane in meltwater runoff in real
time,
they observed that methane was continuously exported from beneath the
ice. They calculated that at least six tons of methane was
transported to their measuring site from this portion of the Ice
Sheet alone, roughly the equivalent of the methane released by up to
100 cows.
Professor
Jemma Wadham, Director of Bristol's Cabot Institute for the
Environment, who led the investigation, said: "A key finding is
that much of the methane produced beneath the ice likely escapes the
Greenland Ice Sheet in large, fast flowing rivers before it can be
oxidized to CO2, a typical fate for methane gas which normally
reduces its greenhouse warming potency."
Methane
gas (CH4) is the third most important greenhouse gas in the
atmosphere after water
vapour and carbon
dioxide (CO2).
Although, present in lower concentrations that CO2, methane is
approximately 20-28 times more potent.
Therefore smaller quantities
have the potential to cause disproportionate impacts on atmospheric
temperatures. Most of the Earth's methane is produced by
microorganisms that convert organic
matter to
CH4 in the absence of oxygen, mostly in wetlands and on
agricultural land, for instance in the stomachs of cows and rice
paddies. The remainder comes from fossil fuels like natural gas.
While
some methane had been detected previously in Greenland ice cores and
in an Antarctic Subglacial Lake, this is the first time that
meltwaters produced in spring and summer in large ice
sheet catchments
have been reported to continuously flush out methane from the ice
sheet bed to the atmosphere.
Lead
author, Guillaume Lamarche-Gagnon, from Bristol's School of
Geographical Sciences, said: "What is also striking is the fact
that we've found unequivocal evidence of a widespread subglacial
microbial system. Whilst we knew that methane-producing microbes
likely were important in subglacial environments, how important and
widespread they truly were was debatable. Now we clearly see that
active microorganisms, living under kilometres of ice, are not only
surviving, but likely impacting other parts of the Earth system. This
subglacial methane is essentially a biomarker for life in these
isolated habitats."
Most
studies on Arctic methane sources focus on permafrost, because these
frozen soils tend to hold large reserves of organic carbon that could
be converted to methane when they thaw due to climate warming. This
latest study shows that ice sheet beds,
which hold large reserves of carbon, liquid water, microorganisms and
very little oxygen – the ideal conditions for creating methane gas
– are also atmospheric methane sources.
Co-researcher
Dr. Elizabeth Bagshaw from Cardiff University added: "The new
sensor technologies that we used give us a window into this
previously unseen part of the glacial environment. Continuous
measurement of meltwater enables us to improve our understanding of
how these fascinating systems work and how they impact the rest of
the planet."
With
Antarctica holding the largest ice mass on the planet, researchers
say their findings make a case for turning the spotlight to the
south. Mr Lamarche-Gagnon added: "Several orders of magnitude
more methane has
been hypothesized to be capped beneath the Antarctic Ice Sheet than
beneath Arctic ice-masses. Like we did in Greenland, it's time to put
more robust numbers on the theory."
More
information: Guillaume
Lamarche-Gagnon et al. Greenland melt drives continuous export of
methane from the ice-sheet bed, Nature (2018). DOI:
10.1038/s41586-018-0800-0
A
NSW council is on the verge of of carting water from 40kms to a
drought-hit town after its dam’s usable water supply fell to five
per cent.
An
emergency bore installed last year has been supplying 70 per cent of
Murrurundi’s needs with the rest coming from the dam and the Pages
River gallery.
The
dam will last for a few months but if the bore fails the council will
cart water for domestic supply to the town in the NSW Upper Hunter
Valley.
Water
carting costs of $1000 a day would be shared by the NSW government
and the council’s water fund which comes from water rates,
shire-wide
Most
countries have not yet met their commitments under the Paris climate
agreements, and Climate Action Tracker rates a small group of
countries as “critically insufficient or highly insufficient.”
These include Russia, Ukraine, Saudi Arabia, Turkey and the US.
Deng
notes that in the US, state and local level governments are working
to find ways to reduce emissions, but at the federal level, under the
Trump administration, there is not only a lack of action but a
reversal of direction.
More
than 1.6 million Sydney residents are at high risk of flooding or
bushfires, new analysis shows, with warnings that without pre-emptive
action even more people will face threats posed by natural disasters.
Special
analysis which maps insurance data and natural peril risk levels
across local government areas in NSW, Victoria and Queensland reveals
millions of residents across the three
“Antarctic
sea ice extent is astonishingly low this year, not just near the Ross
Ice Shelf, but around most of the continent,” says Cecilia Bitz, a
polar scientist at the University of Washington.
Continued
heavy rain and and strong winds in Solomon Islands could lead to more
flash flooding and possible landslides over the next few days.
The
country's met service has issued further heavy rain warnings and
advised all locals to stay indoors while warnings were in place.
Trees
felled and roads flooded but storm appears to have done less damage
than feared
Rain,
wind and surging seawater from a tropical storm has buffeted coastal
villages and tourist resorts on southern Thailand’s east coast,
knocking down trees and utility poles and flooding roads.
One
person was reported dead and another missing after a fishing boat
with a crew of six capsized in high waves, but by nightfall it
appeared that Tropical Storm Pabuk had caused less damage than
feared.
A
fire is burning out of control in the south west of Tasmania. It
started as a result of a lightning strike on December 27. It is being
reported that it has already grown to 10,000 hectares and currently
considered ‘out of control’ and hence fire services are unable to
contain it. The ABC reports that 150 members of the Tasmanian Fire
Service are currently fighting it but ‘there’s no way of stopping
it at this stage’.
It
threatens iconic areas like Lake Rhona and is moving towards Mt Field
National Park and the towns of Maydena, Tyenna and National Park. A
westerly change which is passing through the state could change
direction of the fire so check the Tasmania Fire Service (TFS)
website for details if you’re in the area (see below for all
links).
High
pressure aloft has continued to limit rainfall in southern Brazil
accompanied by some hot weather. In a normal year, this would be
rather early in the growing season and have limited impact on the
crop.
However,
this growing season featured an early start to the rainy season.
Producers took full advantage of this by planting early and planting
shorter-season varieties in Parana to take advantage of an early
harvest.
This
has not worked out well, as the early-planted crop has experienced
hot and dry weather right in the middle of pod fill. This is leading
to some significant crop losses in the major growing areas of western
Parana.
- The Permian period ended about 250 million years ago with the largest recorded mass extinction in Earth’s history, when a series of massive volcanic eruptions is believed to have triggered global climate change that ultimately wiped out 96 percent of marine species in an event known as the “Great Dying.”
- According to Justin Penn, a doctoral student at the University of Washington (UW), the Permian extinction can help us understand the impacts of climate change in our own current era.
- Penn led a team of researchers that combined models of ocean conditions and animal metabolism with paleoceanographic records to show that the Permian mass extinction was caused by rising ocean temperatures, which in turn forced the metabolism of marine animals to speed up. Increased metabolism meant increased need for oxygen, but the warmer waters could not hold enough oxygen to meet those needs, and ocean life was left gasping for breath.
“It
is in the context that the population has already declined 97%. So,
it’s OK if you have millions of butterflies and they drop down a
little bit – that’s not a huge deal. But if you have 200,000
butterflies to begin with and you have a bad year? Now we only have
30,000 left.”
Natural
Bridges State Park, in Santa Cruz, California, found 8,000 monarchs
overwintering in the trees just two years ago. This year, only about
1,000 can be seen, showcasing the alarming trend.
Researchers
cite many factors including: habitat loss and fragmentation in
breeding and overwintering locations, increased use and spread of
pesticides, drought, and severe weath
Environmentalists
are warning the Environmental Protection Agency (EPA) that its draft
plan to continue allowing oil and gas companies to dump unlimited
amounts of fracking chemicals and wastewater directly into the Gulf
of Mexico is in violation of federal law.
In
a letter sent to EPA officials, attorneys for the Center for
Biological Diversity warned that the agency’s draft permit for
water pollution discharges in the Gulf fails to properly consider how
dumping wastewater containing chemicals from fracking and acidizing
operations would impact water quality and marine wildlife
Air
quality index at 12 times US government-recommended level and
visibility low
Delhi
residents woke to a thick, grey smog on Thursday as air pollution in
the Indian capital surged to emergency levels.
The
state-run Central Pollution Control Board’s air quality index,
which shows the concentration of poisonous particulate matter known
as PM 2.5, stood at 440, up from 430 on Wednesday and about 12 times
the US government-recommended level of 35.
Pollution
levels hit 500 in some parts of Delhi, and there was very poor
visibility in some areas. Last year the high was 450 on 23 December.
A
sharp drop in temperatures and wind speed, combined with vehicle and
industrial emissions, dust from building sites and smoke from the
burning of waste, has increased pollution over much of north India
including Delhi, which is home to more than 20 million people.
The
cold weather has forced some people, especially those spending the
night in the open, to burn small fires to keep warm, adding to the
smog.
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