Satellites collect data on sea temperatures, reefs

Brian Skoloff, Associated Press Yahoo News 9 Oct 08;

Satellites are helping scientists expand a virtual network to watch for increases in ocean temperatures that can damage or kill the fragile ecosystems of coral reefs worldwide.

The National Oceanic and Atmospheric Administration said Thursday its Coral Reef Watch network has been expanded from 24 to 190 locations, including sites in the Florida Keys, the Caribbean, Gulf of Mexico, the Indian and Pacific oceans, Indonesia, Australia and Hawaii.

The agency uses onsite water instruments to monitor ocean temperatures at about a dozen reefs. The expanded system uses satellites to remotely monitor water temperature and other factors without the high cost of deploying devices.

A mere 2-degree rise in typical summertime water temperature can stress corals, causing the tiny marine creatures that form reefs to expel algae living in their tissues. The so-called bleaching upsets the symbiotic nature of the ecosystem by exposing their white skeletons.

Many corals can recover from a mild, short-lived bleaching event. But if it occurs over a longer period, entire colonies die. The Caribbean region has lost at least 50 percent of its corals, largely because of warmer seas.

"Bleaching is a major threat to the health of endangered coral reef ecosystems across the earth," NOAA administrator and retired Navy Vice Adm. Conrad C. Lautenbacher said. "The expansion of this critical climate monitoring tool will help us better track, understand and mitigate the impacts of warming waters that contribute to the bleaching damage."

With advance warning, scientists hope environmental managers can limit non-climate related stresses to reefs, such as temporarily halting fishing in an area, limiting public access or stopping nearby construction projects that may be coating corals with sediment.

The more resilient and healthy corals are before a bleaching event, the better chance they'll have to survive and recover. It's the best scientists can do for now to protect reefs, which are suffering worldwide from overfishing, pollution, coastal development and climate change.

"We just need to build up a new body of knowledge and understanding about what works and what doesn't work," said Roger McManus, Conservation International's vice president for global marine programs. "Then we should be able to improve our management."

Corals serve as breeding grounds and habitat for many of the world's marine species and act as indicators of overall ocean health. A study published in the journal Science last year warned that if carbon emissions continue at today's rate, all corals could be extinct within 100 years.

NOAA Coral Reef Watch: http://coralreefwatch.noaa.gov/satellite/current/experimental_products.html

NOAA Coral Bleaching Monitoring Network Now Global
NOAA website 9 Oct 08;

NOAA's Coral Reef Watch bleaching monitoring network has expanded its network of "virtual stations" from 24 to 190 locations worldwide. These stations warn coral reef managers when there is an elevated risk of coral bleaching, based on temperature data from NOAA’s environmental satellites.

The satellite alert system provides approximately two weeks’ advance warning before bleaching occurs, giving reef managers time to respond. The expansion was made possible, in part, through the GEF-World Bank Coral Reef Targeted Research Program. Additional support comes from NOAA's Coral Reef Conservation Program.

"Bleaching is a major threat to the health of endangered coral reef ecosystems across the earth," said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. "The expansion of this critical climate monitoring tool will help us better track, understand and mitigate the impacts of warming waters that contribute to the bleaching damage."

Sea surface temperature data used by Coral Reef Watch comes from NOAA’s Polar-orbiting Operational Environmental Satellites that provide daily coverage of the earth’s surface. Continuous monitoring of sea surface temperature at global scales provides researchers and stakeholders with tools to understand and better manage the complex interactions leading to coral bleaching.

Reef conditions are assessed twice each week, so subscribers have up-to-date information about bleaching risk. The alerts will now cover 190 coral reefs in the Florida Keys, Caribbean, Gulf of Mexico, Indian Ocean, Coral Triangle, Australia’s Great Barrier Reef, Hawaii, and the Pacific Ocean. Products are available from the Coral Reef Watch experimental products webpage.

“We are excited to bring these tools to a wider number of users. Our virtual stations have been very popular with reef managers who use them to monitor temperatures at their reefs” said Mark Eakin, Ph.D., coordinator of NOAA’s Coral Reef Watch. “These are a great addition to our bleaching forecasts that address large regions of the ocean.”

The ocean's temperature is increasing due to climate change. Corals are stressed when water temperature stays two degrees Fahrenheit above the summertime average for a week or more, especially when there are no winds to mix surface waters and provide relief from the strong tropical sun. Stressed corals expel the algae that live in their tissues, exposing the white skeleton underneath. Corals typically recover from mild bleaching, gradually recovering their color by repopulating their algae. However, if the bleaching is severe or prolonged, individual polyps or whole colonies will die.

The ability to predict coral bleaching events and provide advance warning is critically important to sustaining healthy reefs. When coral reef managers and reef users are alerted, they can mobilize monitoring efforts, develop response strategies, and educate reef users and the public on coral bleaching and possible effects on reef resources.

The virtual stations are operated by scientists in NOAA’s Coral Reef Watch in Silver Spring, Md.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.