As sea ice in the Arctic continues to shrink during this century, more than two thirds of the area with sufficient snow cover for ringed seals to reproduce also will disappear, challenging their survival, scientists report in a new study.
The ringed seal, currently under consideration for threatened species listing, builds caves to rear its young in snow drifts on sea ice. Snow depths must be on average at least 20 centimeters, or 8 inches, to enable drifts deep enough to support the caves. (more…)
Arctic crustaceans use currents, deep-water migration to survive sea ice melts
With sea ice in the Arctic melting to record lows in summer months, marine animals living there face dramatic changes to their environment. Yet some crustaceans, previously thought to spend their entire lives on the underside of sea ice, were recently discovered to migrate deep underwater and follow ocean currents back to colder areas when ice disappears.
“Our findings provide a basic new understanding of the adaptations and biology of the ice-associated organisms within the Arctic Ocean,” said Mark Moline, director of the University of Delaware’s School of Marine Science and Policy in the College of Earth, Ocean, and Environment. “They also may ultimately change the perception of ice fauna as imminently threatened by the predicted disappearance of perennial sea ice.” (more…)
The extent of sea ice in the Arctic has reached a record low, according to data released Aug. 26 by the U.S. National Snow and Ice Data Center (NSIDC).
A University of Delaware marine scientist can confirm some of that ice loss firsthand. In a short video he produced, Andreas Muenchow, aboard the Canadian icebreaker Henry Larsen, shows the ice-free sea off Petermann Fjord that he and his colleagues were sailing in — an area that for ages had been covered by floating ice shelves. (more…)
Sustainable management of a huge, complex and valuable resource such as the ocean requires a comprehensive metric that did not exist until now. In the Aug. 16 edition of Nature a broad group of scientists including Heather Leslie, the Sharpe Assistant Professor of Environmental Studies, describes the Ocean Health Index. The index rates coastal places, from regions to nations, on 10 goals: artisanal fishing opportunity, biodiversity, carbon storage, clean waters, coastal livelihoods and economies, coastal protection, food provision, natural products, sense of place, and tourism and recreation. Leslie recently answered questions posed by David Orenstein.
How does the Ocean Health Index’s focus on integrating human factors make it different and valuable?
Recognizing people’s integral roles in ocean ecosystems, this index evaluates how well the ocean provides 10 key benefits to people and how well we are protecting its ability to do so in the future. (more…)
A team of researchers, including scientists from Woods Hole Oceanographic Institution (WHOI), discovered a massive bloom of phytoplankton beneath ice-covered Arctic waters. Until now, sea ice was thought to block sunlight and limit the growth of microscopic marine plants living under the ice.
The amount of phytoplankton growing in this under-ice bloom was four times greater than the amount found in neighboring ice-free waters. The bloom extended laterally more than 100 kilometers (62 miles) underneath the ice pack, where ocean and ice physics combined to create a phenomenon that scientists had never seen before. (more…)
PASADENA, Calif. – Drastic reductions in Arctic sea ice in the last decade may be intensifying the chemical release of bromine into the atmosphere, resulting in ground-level ozone depletion and the deposit of toxic mercury in the Arctic, according to a new NASA-led study. (more…)
The blanket of sea ice that floats on the Arctic Ocean appears to have reached its lowest extent for 2011, the second lowest recorded since satellites began measuring it in 1979, according to the University of Colorado Boulder’s National Snow and Ice Data Center.(more…)
ANCHORAGE, Alaska — USGS Alaska Science Center researchers, in cooperation with the Native Village of Point Lay, will attempt to attach 35 satellite radio-tags to walruses on the northwestern Alaska coast in August as part of their ongoing study of how the Pacific walrus are responding to reduced sea ice conditions in late summer and fall. (more…)
