Environmental News Network: A tiny marine filter-feeder, that anchors itself to the sea bed, offers new clues to scientists studying the stability of the West Antarctic Ice Sheet — a region that is thought to be vulnerable to collapse.
As part of a study for the Census of Antarctic Marine Life (CAML), scientists from British Antarctic Survey (BAS) analysed sea-bed colonies of bryozoans from coastal and deep sea regions around the continent and from further afield. They found striking similarities in particular species of bryozoans living on the continental shelves of two seas — the Ross and Weddell — that are around 1,500 miles apart and separated by the West Antarctic Ice Sheet.
This new finding, published this month in the journal Global Change Biology, leads the science team to conclude that these animals could have spread across both seas only by means of a trans-Antarctic seaway through what is now a 2 km solid layer of ice. They suggest also that this seaway opened up during a recent interglacial (warm period between ice ages) perhaps as recently as 125,000 years ago when sea level was about 5 metres higher than today.
While some geological evidence suggests that the West Antarctic Ice Sheet (WAIS) collapsed at least once in the last million years, scientists are keen to determine the frequency of collapse and to understand the processes and connections between warm periods and deglaciation events. Elsewhere around Antarctica the marine animals that could help scientists estimate the date when West Antarctica was ice free, were obliterated during ice ages by advancing glaciers that bulldozed their fossil remains off the continental shelf.
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Environmental News Network: Today NOAA reopened 4,281 square miles of Gulf waters off western Louisiana to commercial and recreational fishing. The reopening was announced after consultation with FDA and under a re-opening protocol agreed to by NOAA, the FDA, and the Gulf states.
On July 18, NOAA data showed no oil in the area. Light sheen was observed on July 29, but none since. Trajectory models show the area is at a low risk for future exposure to oil, and fish caught in the area and tested by NOAA experts have shown no signs of contamination.
“Scientists, food safety experts, members of the fishing industry and local, state, federal officials, are working together every day to ensure that seafood from the Gulf is safe to eat,” said Jane Lubchenco, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. “We will remain vigilant and continue to monitor and test seafood in reopened waters.”
Between July 26 and July 29, NOAA sampled the area for both shrimp and finfish, including mackerel and snapper. Sensory analyses of 41 samples and chemical analyses of 125 specimens that were composited into 14 samples followed the methodology and procedures in the re-opening protocol, with sensory analysis finding no detectable oil or dispersant odors or flavors, and results of chemical analysis well below the levels of concern.
At its closest point, the area to be reopened is about 185 miles west of the Deepwater/BP wellhead. The entire area is heavily fished by fishermen targeting reef fish, menhaden and shrimp.
“Because of our strict adherence to the reopening protocol agreed to by the states and the federal government we have confidence that seafood harvested from this area is free from harmful oil residues and can be enjoyed by consumers around the nation,” said Margaret Hamburg, M.D., Commissioner of the Food and Drug Administration.
NOAA will continue to take samples for testing from the newly re-opened area, and the agency has also implemented dockside sampling to test fish caught throughout the Gulf by commercial fishermen.
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Environmental News Network: The geography of Indonesia is dominated by volcanoes that are formed due to subduction zones between the Eurasian plate and the Indo-Australian plate. Some of the volcanoes are notable for their eruptions, for instance, Krakatau for its global effects in 1883, Lake Toba for its supervolcanic eruption estimated to have occurred 74,000 Before Present which was responsible for several years of cold of volcanic winter, and Mount Tambora for the most violent eruption in recorded history in 1815. Indonesia’s Mount Sinabung has recently erupted, two days after it sprang back into life after over 400 years of inactivity.
Volcanoes in Indonesia are a part of the Pacific Ring of Fire
. There are about 150 known volcanic sources. Most are in what is called the Sunda Arch (Sumatra and Java). The remaining volcanoes are those of Halmahera, including its surrounding volcanic islands, and the volcanoes of Sulawesi and the Sangihe Islands. The latter group is in one volcanic arc together with the Philippine volcanoes.
The most active Indonesian volcanoes are Kelut and Merapi on Java island which have been responsible for thousands of deaths in the region. Since AD 1000, Kelut has erupted more than 30 times. While Merapi has erupted more than 80 times.
The first eruption of Mount Sinabung — which caught many scientists off guard since the volcano is not as closely monitored as other volcanoes — over the last August weekend was followed by a second, more powerful blast on August 30th that spewed soot and debris more than a mile into the air, leaving the region on high hazard alert.
Mount Sinabung last erupted in 1600 and government vulcanologists acknowledged they had made no efforts before the mountain started rumbling last week to sample gases or look out for rising magma or other signs of seismic activity.
The Indonesian government was reported to have evacuated around 17,500 people from the region on and around the volcano.[11] The government issued the highest-level warning for the area, which was expected to remain in force for around a week, since scientists were unfamiliar with the characteristics of the volcano, due to it having been dormant for so long.
Indonesia is prone to earthquakes, volcanic eruptions, and the occasional tsunami. It can well be considered a very dangerous place to live despite its beauty due to these tectonic caused effects. Yet geothermal power in Indonesia is an increasingly significant source of renewable energy. As a result of its volcanic geology, Indonesia has about 40% of the world’s potential geothermal resources. To live well one may have to live dangerously.
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