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Scientists say coral reef levels remain the same
Coral reefs around the world could expand in size by up to a third because of increased ocean warming, according to a new Australian study which contradicts the long-held belief that global warming is destroying the reefs.
Previous research has predicted a decline of between 20 to 60 per cent in the size of coral reefs by 2100 relative to
pre-industrial levels because of increasing carbon dioxide (CO2) levels caused by the greenhouse effect in ocean surface waters.
But the newly published research, by a team led by oceanographer Ben McNeil of Sydney’s University of New South Wales, suggests that present coral reef calcification rates are not in decline and are equivalent to late 19th century levels. “Our analysis suggests that ocean warming will foster considerably faster future rates of coral reef growth that will eventually exceed pre-industrial rates by as much as 35 percent by 2100.Our finding stands in stark contrast to previous predictions that coral reef growth will suffer large, potentially catastrophic, decreases in the future.”
Experts say seawater surface temperatures and the quantity of carbonate in seawater dictate the growth rate of coral reefs which are built from calcium carbonate when red algae cement together a framework of coral skeletons and sediments.
Australian scientists have observed the calcification-temperature relationship at significant reef-building colonies around the world in the Indo-Pacific and at massive Porites reef colonies in Australia, Hawaii, Thailand, the Persian Gulf and the South Pacific island of New Ireland.
Who needs chemo for cancer
A new genetic test can tell doctors which breast cancer patients need to undergo the discomfort of chemotherapy — and suggests many women don’t need to, researchers said last week.
Almost half of US women diagnosed with a specific form of breast cancer — estrogen-dependent cancer that has not yet spread — can skip the chemo, the results suggest. That means about 25,000, mostly older women a year, according to the National Cancer Institute, which helped sponsor the study.
“The test has the potential to change medical practice by sparing thousands of women each year from the harmful short- and long-term side effects associated with chemotherapy,” said Dr JoAnne Zujewski of the NCI’s Cancer Therapy Evaluation Program.
The study results, released early by the New England Journal of Medicine and also at the San Antonio Breast Cancer Symposium, are based on a study of gene activity in the breast cancer tumours.
Dr Soonmyung Paik and colleagues at the University of Pittsburgh and elsewhere used tissue samples from women enrolled in past clinical trials of the cancer drug tamoxifen, which blocks the effect of estrogen on breast cancer cells.
About 80 percent of breast cancer patients have the kind of cancer that responds to hormone-based therapy like tamoxifen, and the drug has been shown to reduce the cancer’s spread.
But the question has been
who can safely get away with just surgery and either tamoxifen or newer, hormone-based drugs called aromatase inhibitors.
Alaska oil spill
About 150 people were ready to begin cleaning up an oil spill threatening endangered animals on Sunday, four days after a ship broke apart and six people died in a helicopter rescue attempt.
The cargo ship broke apart during a storm off the coast of an Alaska island, and weather has calmed, allowing environmental crews to start work.
Assessment teams were able to conduct an aerial survey, and a research vessel with wildlife experts was headed to the spill site, on the western coast of Unalaska Island in the Aleutian chain, officials said.
The island is about 800 miles southwest of Anchorage; the wreck site is on its western shore, an area without road links to the port city of Unalaska/Dutch Harbor on the north part of the island. — Dawn Sci-tech World Report
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