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Coral in Caribbean, Florida in sharp decline, ‘no signs of slowing,’ report finds
NBC,
7
September, 2012
Reefs
in the Caribbean and Florida Keys have lost most of the colorful
corals that feed a rich ecosystem and made the region a diving and
snorkeling mecca, a major conservation group reported Friday. On
average, reefs have live coral on just 8 percent of their surface
area, down from more than 50 percent in the 1970s.
Impacts
including warming seas and human sewage have contributed to a steady
decline that shows "no signs of slowing," the International
Union for Conservation of Nature (IUCN) said in releasing its report,
which was based on new data compiled by 36 experts earlier this year.
With
food scarce from drought, desperate animals enter towns – ‘Right
now, they’d eat about anything’
6
September, 2012
People
move to the mountains to be closer to nature. But not this close.
At
least two candy stores have been burglarized this summer by ravenous,
drought-starved bears. They are being struck by cars as they roam
dark highways, far from their normal foraging grounds. Growing
numbers are invading campsites and kitchens in search of food. One
even tried to storm a hotel bar in Telluride, Colorado.
In
addition to destroying crops, this summer’s record-breaking drought
has also killed off the wild acorns, berries and grasses that sustain
animals like mule deer, elk and bears. Without that food, the great
outdoors is pushing its way inside, looking for calories wherever
they can be found.
Elk
and mule deer are stealing into farmers’ corn and alfalfa fields
more aggressively, and in greater numbers, than usual, wildlife
officials say. Bears have been spotted lumbering through alleys,
raiding garbage cans and scooting into people’s homes through open
windows and unlocked kitchen doors.
Increase
in Total Annual Precipitation in the U.S. versus Storm Size,
1948-2011
This
figure shows that the very largest storms are getting bigger, faster,
than other storms. All storm categories are defined relative to the
local climate at each weather station used in this analysis. For
example, the far right column represents the change over time in the
amount of total precipitation produced by the largest 0.1 percent of
storm events at each weather station we used across the contiguous
United States.
The
trends toward more frequent and more intense rainstorms and
snowstorms were even more pronounced and substantial for larger
events. In other words, the most extreme storms are those that have
experienced the greater increase in their likelihood.
http://pennenvironmentcenter.org/reports/pac/when-it-rains-it-pours?__utma=1.465737158.1344215436.1344215436.1344215436.1&__utmb=1.4.10.1344215436&__utmc=1&__utmx=-&__utmz=1.1344215436.1.1.utmcsr=bing|utmccn=(organic)|utmcmd=organic|utmctr=PennEnvironment&__utmv=-&__utmk=32442046
New
Zealand court rejects global warming challenge from denialists
7
September, 2012
New
Zealand's High Court on Friday dismissed a challenge launched by
climate change sceptics against a government research agency's
finding that the temperature had risen in the past century.
The
court backed the science that led the National Institute of Water and
Atmospheric Research (NIWA) to conclude that New Zealand's climate
warmed almost one degree Celsius (1.8 degrees Fahrenheit) between
1909 and 2009.
New
Zealand Climate Science Education Trust, a private body that rejects
the argument that human activity has caused global warming, went to
court alleging NIWA's methodology was flawed and its findings were
not peer reviewed.
Judge
Geoffrey Venning rejected the allegations in a written ruling handed
down Friday, saying NIWA acted "in accordance with
internationally recognised and credible scientific methodology".
Hurricanes
whip up faster in warming world, says new study
7
September, 2012
Global
warming may fuel stronger hurricanes whose winds whip up faster, new
research suggests.
Hurricanes
and other tropical cyclones across the globe reach Category 3 wind
speeds nearly nine hours earlier than they did 25 years ago, the
study found. In the North Atlantic, the storms have shaved almost a
day (20 hours) off their spin-up to Category 3, the researchers
report. (Category 3 hurricanes have winds between 111 and 129 mph, or
178 and 208 kph.)
"Storms
are intensifying at a much more rapid pace than they used to 25 years
back," said climatologist Dev Niyogi, a professor at Purdue
University in Indiana and senior author of the study.
The
work helps support the theory that rising ocean temperatures have
shifted the intensity of tropical cyclones, which include hurricanes
and typhoons, to higher levels. In the past century, sea surface
temperatures have risen 0.9 degree Fahrenheit (0.5 degree Celsius)
globally. Scientists continue to debate whether this increase in
temperature will boost the intensity or the number of storms, or
both. Globally, about 90 tropical cyclones, on average, occur every
year.
Tropical
cyclones form when warm, moist air over the ocean surface fuels
convection. The storms act like heat engines: The warmer the ocean
surface, the more energy there is to power a storm's fierce winds. As
such, scientists have hypothesized global warming and the associated
rising heat of sea surfaces would fuel intense hurricanes.
Most
of the initial strengthening of storms, from Category 1 to Category
3, happens on the open ocean, not as a storm is approaching land. So
even if storms are intensifying more quickly, it may not result in
higher peak wind speeds and more rainfall when hurricanes make
landfall. (Category 1 storms have wind speeds of at least 74 mph, or
119 kph.) [5 Hurricane Categories: Historical Examples]
But
Niyogi and his colleagues found an overall shift toward more intense
storms in all ocean basins except the East Pacific. "They are
getting stronger more quickly, and also higher category. The
intensity as well as the rate of intensity is increasing," said
Niyogi. And that makes it a simple numbers game - with more strong
storms forming in the oceans, the chance of having powerful
hurricanes hit the coast rises.
"If
storms in general are intensifying faster, then these storms making
landfall could have a greater probability of being stronger storms,"
Niyogi told LiveScience.
The
researchers also report that storms in the North Atlantic now
typically mature from a Category 1 to a Category 3 in 40 hours
instead of the 60 hours that transition took 25 years ago. (Hurricane
Michael, currently swirling far out over the Atlantic went from a
Category 1 hurricane to a Category 3 in about 6 hours, according to
reports from the National Hurricane Center.)
The
North Atlantic basin also shows the strongest warming trends during
the study period. In the past 30 years, sea surface temperatures in
Hurricane Alley - the main Atlantic hurricane development region -
increased nearly 2 degrees Fahrenheit (1 degree Celsius).
The
research is detailed in the 26 May 2012 issue of the journal
Geophysical Research Letters. […]
But
the risk of damage from stronger storms is outweighed by the expected
financial hit from people putting themselves in harm's way, according
to a study published in the 28 August 2012 issue of Geophysical
Research Letters. […]
Glacial
thinning has sharply accelerated at major South American icefields
7
September, 2012
The
thinning of the Grey Glacier in Patagonia is visible by comparing the
current glacier with the bottom of the vegetation line on the
surrounding mountains - where the glacier reached until recently.
(Credit: Rivera). For a larger version of this image please go here.
For
the past four decades scientists have monitored the ebbs and flows of
the icefields in the southernmost stretch of South America's vast
Andes Mountains, detecting an overall loss of ice as the climate
warms. A new study, however, finds that the rate of glacier thinning
has increased by about half over the last dozen years in the Southern
Patagonian Icefield, compared to the 30 years prior to 2000.
"Patagonia
is kind of a poster child for rapidly changing glacier systems,"
said Michael Willis, lead author of the study and a research
associate at Cornell University in Ithaca, New York. "We are
characterizing a region that is supplying water to sea level at a big
rate, compared to its size."
The
Southern Patagonian Icefield together with its smaller northern
neighbor, the Northern Patagonian Icefield, are the largest icefields
in the southern hemisphere - excluding Antarctica. The new study
shows that the icefields are losing ice faster since the turn of the
century and contributing more to sea level rise than ever before.
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