CORAL DILEMMA 

Coral reefs are nicknamed "rain forests of the sea" because of their rich biodiversity, but according to a new report, they also share something else with rain forests: a grim future. "Currently, we find 75 percent of the world's reefs are threatened by a combination of local and global threats," says Lauretta Burke of the World Resources Institute, one of 25 research organizations that contributed to the report. "By 2030, the percentage will rise to 90 percent. By 2050, virtually all reefs will be threatened."

Titled "Reefs at Risk Revisited," the report is an update to a previous study on the world's coral reefs, and it finds plenty to be concerned about. Longstanding threats like overfishing and local pollution are growing in many areas, especially developing countries, but not even well-managed reefs like Australia's can escape the more recent and pervasive danger of climate change. "Warming seas have already caused widespread damage to reefs, with high temperatures driving a stress response called coral bleaching, where corals lose their colorful symbiotic algae, exposing their white skeletons," the report says. "In addition, increasing carbon dioxide emissions are slowly causing the world's [skipwords]oceans[/skipwords] to become more acidic. Ocean acidification reduces coral growth rates and, if unchecked, could reduce their ability to maintain their physical structure."

The loss of coral reefs wouldn't just be an ecological disaster, but an economic one, too. A U.N. report last year estimated that 30 million people worldwide are "totally reliant" on reefs for food and income, and pegged coral's global economic value at $172 billion. Losing that would certainly be a big blow, but the "Reefs at Risk" authors are also careful to point out that it's not yet too late to prevent their forecast from coming true. "These are dire projections," Burke says, but adds that it doesn't have to be that way. "These results assume no improvement in management, no reduction in local threats, and that we continue on our current trajectory of greenhouse gas emissions." 

(Sources: WRI, NPR, Guardian, Sydney Morning Herald, Underwater Times)

UNCLEARING THE AIR 

The Obama administration issued revised air pollution rules Wednesday, adjusting to a new political climate by scrapping tougher restrictions it had proposed last year and instead making life easier for thousands of industrial boilers and incinerators around the country. The move is a big departure from the EPA's previously strong stance against emissions of lead, mercury, soot and other toxic gases, but the agency says its new rules will achieve similar health benefits at half the cost. 

"These health protections will save between $23 billion and $56 billion in health-related costs," EPA air and radiation director Gina McCarthy told reporters Wednesday in a conference call. "They are realistic, they are achievable, and they are reasonable, and they come at roughly half the cost to comply compared to that in the proposed rule in May 2010." The EPA already withdrew that rule late last year, but while the agency wanted another 15 months to work out the kinks, a federal judge ordered it to produce revised rules by this week. Complaints against the original rule were almost entirely about economics — one industry-funded study suggested it would cost businesses $20 billion and force them to cut more than 300,000 jobs. The new rule, according to the EPA's figures, will cost $2.1 billion a year and will generate more than 2,000 new jobs. Plus, McCarthy says it also still meets its original goal: saving lives. She says the pollution cuts would save 2,600 to 6,600 lives annually by 2014, and prevent 4,100 heart attacks and 42,000 asthma attacks each year.

The rule update comes at a time when the EPA faces intense scrutiny on Capitol Hill, and likely reflects a bit of political maneuvering from the Obama administration. While the court-ordered deadline forced the agency's hand this week, President Obama and EPA Administrator Lisa Jackson may also be trying to stockpile political capital for their upcoming plans to regulate carbon dioxide emissions from industrial sources. For now, at least, they seem to have appeased industry advocates. "This is a good plan given our nation's current economic challenges," the president of the Council of Industrial Boiler Owners tells the New York Times. "It makes much more sense for EPA and all stakeholders to revisit key challenges, take additional time and get the rule right."

(Sources: Associated Press, New York Times)

BLOW AND THE WIND 

If you regularly breathe in air pollution, you may face an even higher risk of heart attacks than a cocaine addict does. That's according to a new study in the journal Lancet, which finds that air pollution poses a higher overall cardiac risk than cocaine use, and at least as high a risk as alcohol, caffeine and physical exercise. The study's authors say it should remind doctors not to ignore population-level risks like air pollution in favor of more individual factors like diet and exercise.

"Physicians are always looking at individual patients — and low risk factors might not look important at an individual level, but if they are prevalent in the population then they have a greater public health relevance," lead author Tim Nawrot of Hasselt University in Belgium tells Reuters. The researchers examined data from 36 separate heart-attack studies, calculating the proportion of total heart attacks caused by a variety of triggers. Of all the potential heart-attack triggers they studied, exposure to vehicle traffic was the highest, followed by physical exertion, alcohol, coffee, air pollution, anger, sex and cocaine use. "Of the triggers for heart attack studied, cocaine is the most likely to trigger an event in an individual, but traffic has the greatest population effect as more people are exposed to [it]," the researchers wrote.

While the new study highlights the often-overlooked dangers of urban air pollution, other heart experts tell Reuters such triggers are just the tip of the iceberg. Reducing exposure to air pollutants is certainly a good idea, but the battle against heart disease is much more complicated and long-term. "What triggers the heart attack should be considered the 'last straw,'" says University of Sheffield heart specialist Tim Chico. "The foundations of heart disease that lead to a heart attack are laid down over many years. If someone wants to avoid a heart attack, they should focus on not smoking, exercising, eating a healthy diet and maintaining their ideal weight."

(Source: Reuters)

FINAL COUNTDOWN 

The space shuttle Discovery is set to lift off into space for the last time today, with the weather at Cape Canaveral, Fla., looking clear and NASA giving 90 percent odds that the launch will take place as planned. Discovery was supposed to take its final flight last year, but was delayed for four months by frequent hydrogen leaks and fuel-tank cracks that forced NASA to repeatedly reschedule. Finally, however, the aging shuttle seems ready for its swan song this afternoon at 4:50 Eastern time.

Discovery has been ferrying astronauts to space for nearly three decades, having already taken 38 trips off the planet during its tenure. It has spent 352 days in orbit, circled the Earth 5,628 times and carried a total of 246 crew members, more than any other spacecraft in history. Its last six-member crew will be transporting equipment to the International Space Station for the shuttle's 39th and final flight, including a storage module, a science rig and various other spare parts. It will be piloted by astronaut Steve Bowen, who's taking over from Tim Kopra after Kopra was recently injured in a bicycle accident. 

NASA is winding down its shuttle program as part of a broader push to privatize much of the space agency's routine space-flight work, freeing it up to focus on big-picture missions like landing on Mars and an asteroid. Discovery will be the first shuttle to retire, followed by Endeavour, which is scheduled for its last pre-retirement takeoff on April 19. The third and final shuttle, Atlantis, is tentatively slated to carry out NASA's very last shuttle launch sometime this summer.

(Sources: CNN, USA Today, Space.com)

THIS DAY IN HISTORY

The New York Times ponders a new ice age, a Sea World trainer is killed, and more.

Russell McLendon

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Photo (coral reef): National Oceanic and Atmospheric Administration

Photo (industrial emissions from factories): ZUMA Press

Photo (lines of cocaine with a razor): Jupiter Images

Photo (Discovery shuttle at Kennedy Space Center): ZUMA Press

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