Study tracks blue whales across Southern Ocean

New data will help shape conservation efforts in the waters around Antarctica

Naval training exercises off the coast of California could pose a threat to endangered marine mammals.

Australian and New Zealand researchers have tracked blue whales across thousands of miles in the Southern Ocean to help inform conservation efforts. Photo courtesy NOAA.

Staff Report

FRISCO — As a keystone species in marine ecosystems, blue whales have a significant impact in the ocean around Antarctica, but the population dynamics of the species in the region are still a mystery as the marine mammals recover from the decimation of the whaling era.

That may change following the recent six-week Australia-New Zealand Antarctic Ecosystem Voyage voyage, as researchers tracked the world’s largest creatures across thousands of miles of ocean, detecting their songs from as far as 750 kilometers away. Continue reading

How do Antarctica snowfall rates affect sea level rise?

New ice core analysis shows less of an ‘offset’ than most models currently project

Antarctica permafrost

Increasing snowfall in Antarctica will moderate the rate of global sea level rise — but not as much as previously thought. bberwyn photo.

Staff Report

FRISCO — Detailed ice core records from Antarctica show that snowfall over the frozen continent increased about 5 percent for each degree (Celsius) of warming as Earth emerged from the last ice age.

The findings confirm that the increased snowfall will slightly offset sea level rise, as suggested by other research — but not as much as previously thought. That means that some computer models may be underestimating the amount and rate of future sea level rise if they’re based on inaccurate assumptions. Continue reading

Shifting Southern Ocean winds regulate pace of global warming

sadfg

Southern Ocean winds and currents are key regulators of global temperature and carbon cycles.

Strengthening eddies drive heat deep into the sea

Staff Report

FRISCO — Shifting wind patterns across the Southern Ocean around Antarctica are having a big effect on the carbon cycle and on the heat transfer between the ocean and the atmosphere.

The changes are so profound that they are actually delaying the effects of global warming, according to a new study published in the Journal of Physical Research.

“Considering the Southern Ocean absorbs something like 60 percent of heat and anthropogenic CO2 that enters the ocean, this wind has a noticeable effect on global warming,” said lead author Dr Andy Hogg from the Australian National University Hub of the ARC Centre of Excellence for Climate System Science. Continue reading

Climate: Study shows that just a little bit of warming could destabilize West Antarctic ice sheets

Meeting in Uruguay, an Antarctic science committe advocated for the 2012 establishment of marine reserves in the Southern Ocean and the Ross Sea. PHOTO BY BOB BERWYN.

Will the West Antarctic Ice Sheet slip-slide away as the Southern Ocean warms up? bberwyn photo

A delicate balance

Staff Report

FRISCO — West Antarctica ice sheets are delicately anchored in place along a narrow sliver called the grounding zone, and new research shows that even slight increases in regional ocean and air temperatures are likely to destabilize the ice. The grounding zone is a sloping rock bed that lies below sea level.

In the new study, published this month in the Journal of Glaciology, Caltech scientists said future estimates of sea level rise need to take into account that the ice sheets are more sensitive to temperature perturbations driven by climate change than previously thought.

“Our results show that the stability of the whole ice sheet and our ability to predict its future melting is extremely sensitive to what happens in a very small region right at the grounding line. It is crucial to accurately represent the physics here in numerical models,” said study coauthor Andrew Thompson, an assistant professor of environmental science and engineering at Caltech. Continue reading

Climate: Too cold for penguins?

Emperor penguin colony near Halley Bay. IMAGE COURTESY DIGITALGLOBE.

Emperor penguin colony near Halley Bay. IMAGE COURTESY DIGITALGLOBE.

Genetic study tracks history of Antarctica’s emperor penguin populations

Staff Report

FRISCO — A genetic study shows that emperor penguins may have just barely survived the last ice age, with a few scattered populations  enduring centuries of bitter cold and ice.

The study covers about 30,000 years and suggests that only three populations survived, including a climate refuge of sorts in the Ross Sea, where emperors may have been able to breed around a relatively small area of open water. The emperor penguins in that region evolved to become genetically distinct from other populations, which may support arguments for creating a Ross Sea marine protected area. Continue reading

Climate: NASA study confirms global sea ice decline

lkh

Antarctic sea ice has expanded in the past few years, but overall, the planet is still losing an area of ice the size of Vermont and New Hampshire combined each year. bberwyn photo.

Growth in Antarctic ice extent doesn’t cancel out Arctic decline

Staff Report

FRISCO — NASA researchers who took a close look at both Arctic and Antarctic sea ice say that, overall, Earth has been losing ice at an average rate of about 13,500 square miles per year since 1979, equivalent to an area about the size of Maryland. Continue reading

East Antarctica ice sheets not immune to global warming

An international research team explores the geological history of the Gamburtsev Mountains, buried under two miles of ice in eastern Antarctica.

New research shows that even the frigid fringes of East Antarctica are melting away under warming seas.

Warming ocean melts ice from below

Staff Report

FRISCO — It’s not just the West Antarctic ice sheets that are melting away as the surrounding ocean warms, Australian scientists reported after a six week voyage to the eastern side of the frozen continent.

A series of detailed measurements show that warm ocean water is melting the Totten Glacier — the largest in the region, with enough ice to raise sea level by several meters, according to the findings by the Australian Antarctic Division and partnering research organizations. Continue reading

Follow

Get every new post delivered to your Inbox.

Join 8,204 other followers