Long-term studies show potential impacts of climate change
A new set of scientific reports highlights the value of long-term observations in relatively undisturbed ecosystems and also offers a preview of how global warming may change Antarctica in coming decades.
The research shows that a period of unusual warmth in 2001 and 2002, caused by a confluence two natural climate cycles, accelerated the microbial food chain and shook up the distribution of penguin populations and thinned glaciers according to October issue of the journal BioScience .
The research came out of two long-term ecological research stations, including Palmer Station, on the West Antarctic Peninsula, where scientists study how “changing sea ice extent influences marine ecology and the multilayered food webs of the coastal, nearshore, and continental slope ecosystems.” Other studies were done at the McMurdo Dry Valleys LTER, in an ice-free polar desert where glacial meltwater plays a huge role in ecosystems. Continue reading “How will Antarctica respond to global warming?”→
British researchers say regional patterns of melting of glaciers on the Antarctic Peninsula are linked with warming oceans in the region. The Antarctic Peninsula is one of the biggest contributors to sea level rise, so the new finding will help pinpoint how fast and how high seas will rise in the decades ahead.
A series of research dives around the Antarctic Peninsula suggest that melting glaciers are diminishing the region’s biodiversity. Scientists think the main cause may be increased levels of sediment in the water.
‘The Antarctic Peninsula can be considered an early warning system … ‘
FRISCO — Antarctic icebergs set free to roam near the shore by global warming are fundamentally changing the seafloor ecology, according to researchers with the British Antarctic Survey.
Boulders on the shallow seabed — once encrusted with a rich assemblage of species in intense competition for limited space — now mostly support a single species. The climate-linked increase in iceberg activity has left all other species so rare as to be almost irrelevant, according to the new study published in the Cell Press journal Current Biology on June 16.
“The Antarctic Peninsula can be considered an early warning system—like a canary in a coal mine,” says David Barnes of the British Antarctic Survey. “Physical changes there are amongst the most extreme and the biology considered quite sensitive, so it was always likely to be a good place to observe impacts of climate change—but impacts elsewhere are likely to be not too far behind. A lot of the planet depends on the near-shore environment, not least for food; what happens there to make it less stable is important.” Continue reading “Climate: Icebergs scouring biodiversity from sea-bottom boulders around the Antarctic Peninsula”→
More record-warm Antarctica temperatures recorded in September
By Summit Voice
FRISCO — While scientists recently pinpointed areas with all-time record low temperatures in Antarctica, the South Pole is not immune to global warming — scientists based at the bottom of the world say the past winter was the warmest since record-keeping started in 1957.
In August, for example, the average temperature for the month was more than 11 degrees Fahrenheit above average, at minus 63.9 degrees Fahrenheit.
The trend continued into the Austral spring, with September 2013 also ending up as an all-time record warm month, including four daily maximum temperature records, according to the Antarctic Sun.
That’s not to say the weather was balmy — the average annual temperature at the South Pole is about minus 56.9 degrees Fahrenheit. The coldest reading on record was minus 117 degrees Fahrenheit, set June 23, 1982, while the warmest temperature recorded since 1957 was just a few years ago, Christmas Day, 2011, when the official high was 9.9 degrees Fahrenheit. Continue reading “‘Heatwave’ at South Pole sets records”→
Underwater mountains help churn up the ocean, fueling the carbon cycle
By Summit Voice
FRISCO — The Drake Passage, between the tip of South America and the Antarctic Peninsula, is well known for wild storms and big swell, but it turns out that turbulence isn’t just at the surface.
Far beneath the breaking whitecaps, the area is a crucial ocean mixing ground, where surface water is exchanged with deep water as currents rush over undersea mountains. Those mixing of water layers are crucial to regulating the Earth’s climate and ocean currents, according to researchers who recently traced how that mixing happens. Continue reading “Oceans: Drake Passage seen as mixing ground”→
FRISCO — Finding ways to assess the impacts of global warming in Antarctica isn’t always easy. Measurements of ice help show some of the changes but don’t tell the whole story, so British researchers took a close look at a 150-year-old moss bank on the Antarctic Peninsula, one of the fastest-warming regions on Earth.