Daily News Photo by CRISTIAN SIMESCU National Oceanic and Atmospheric Administration senior scientist William Skirving talks Monday about the agency's work in developing devices to better monitor coral bleaching during a Nature Conservancy workshop on St.

ST. CROIX - National Oceanic and Atmospheric Administration scientist William Skirving can spot a warming ocean from miles away.

Utilizing the latest satellite data and technology, Skirving and his colleagues at NOAA are keeping a close eye on the world's waters from high above the Earth's atmosphere. With sensitive instruments capable of detecting minute temperature changes in a water layer only as thick as a human hair, the group is building powerful new tools to help local environmental managers better understand the fickle moods of the oceans and their consequences for coral reefs.

Skirving, who works with NOAA's Coral Reef Watch project, presented the project's newest tools and the science behind them to a group of the territory's environmental stakeholders on St. Croix Monday. With more than two dozen representatives from local and national agencies including the Ocean Conservancy, the National Park Service, NASA, the Department of Planning and Natural Resources, the University of the Virgin Islands and the Nature Conservancy - which is hosting the event - Skirving kicked off a three-day workshop centered on coral monitoring and investigations of bleaching incidents.

The Caribbean is still recovering from one of the worst coral bleaching incidents in the monitored history of the area. With ocean temperatures soaring this summer and into the fall, many corals in the territory's waters bleached, shedding their all-important algae. Some of the corals regained their algae when the waters cooled in October, but others have died.

Skirving and his colleagues are working hard to develop better monitoring techniques for the area, and he said he hopes eventually to predict the bleaching events by monitoring a host of factors.

"These conditions are not random and are repeatable," Skirving said.

Stagnant waters and clear skies - not global warming - are the culprits in bleaching events, Skirving explained Monday. The upper layers of waters with little wind on their surfaces heat up quickly. Normal wave, wind and tidal actions mix cooler water up from the deep, but when the winds and waves die down, the temperatures climb.

High ocean temperatures this summer were responsible for the bleaching, which occurs when corals under stress expel the algae that live within them. The algae help provide energy and food to the corals through photosynthesis, and corals usually do not survive long periods without the algae.

Skirving walked workshop participants through the science of wind, water and tidal mixing, using examples from his studies of the Great Barrier Reef in Australia, where he was able to separate areas that were somewhat protected from bleaching from those more vulnerable to the incidents.

In areas with stronger tidal currents and wave swells, corals survive longer because of greater mixing, he said. In other areas, where those currents are weak and the waters calm, bleaching occurs more quickly.

Skirving said that a similar approach could be used to analyze patterns in the Caribbean. He said that NOAA is also working to more accurately assess exactly how much warmth for how long in what conditions induces the bleaching, in hopes of building a predictive model.

"We're already working on that," he said. "We need to get targeted weather predictions and some things aren't available yet."

Skirving said some meteorological predictions, such as how much cloud cover is likely over an area of the ocean, have not been perfected yet, but have huge impacts on the potential for bleaching.

NOAA already has produced tools that can monitor worldwide ocean surface temperatures, the cumulative effect of those temperatures and even issue alerts for areas that are becoming likely to bleach.

Unfortunately, even when the scientists can see a bleaching event beginning, they are powerless to stop it.

"A predictive, notification system is great," said Department of Planning and Natural Resources representative Aaron Hutchins. "But what to do next is another issue."

The workshop continues today at the Nature Conservancy's offices in Little Princess, with a discussion of bleaching hot spots in the morning. The afternoon session today and on and Wednesday will be devoted to an analysis of this summer's bleaching event.

- Contact Patrick Joy at 774-8772 ext. 458 or e-mail pjoy@dailynews.vi.