Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA learning to monitor coral reef health from the sky

15.12.2003


Coral reef health may be accurately estimated from sensors on airplanes and satellites in the future, according to a NASA scientist who is the principal investigator in a collaborative project to develop a method to remotely sense coral health.


Checking Coral Health Researchers using handheld ’spectroradiometer’ measure reflected light readings from Acropora palmata, or elkhorn coral to determine the reef health in the Bahamas. The collected data is compared to the reading taken during aerial surveys. Credit: NASA Ames


Elkhorn Coral Acropora palmata, or elkhorn coral exhibiting white band disease. Acropora palmata is a major reef-building coral prevalent in the Bahamas, but is suffering from ’white band disease.’ Elkhorn coral has severely declined in many areas of the Caribbean and may be on the verge of becoming an endangered species. Credit: NASA Ames



Sometimes called the "bellwether of the seas," coral reefs can give first indications of marine ecosystem health. "Scientists can use coral health as a sensitive indicator of the health of the marine environment," said Liane Guild, a scientist at NASA Ames Research Center, Moffett Field, Calif.

"We’re looking into how you could remotely detect coral reef health using aircraft with visible light sensors," Guild said. "First, we have to look at the coral close up, underwater, to see what spectral reflectance the sensor picks up from diseased, stressed and healthy coral."


One of the first steps her team took to develop aerial coral monitoring was to take undersea light-reflectance readings of elkhorn coral with a handheld spectroradiometer, or light meter. A team of four scuba divers, from the Universities of Miami, South Florida and Puerto Rico, helped Guild take the first readings at varying depths in summer 2002 near Andros Island, Bahamas, with assistance from the U.S. Navy Atlantic Undersea Test and Evaluation Center. A spectroradiometer measures the amount of ultraviolet, visible and infrared light reflected from an object, and is similar to sensors aboard remote-sensing airplanes and satellites.

"We moved up from the coral, little by little, to the surface to learn how light intensity decreases in the water column, which affects our coral reflected-light readings," Guild said. "There also will be a layer of atmosphere between the coral, the water and the sensor when it eventually flies aboard an airplane to survey the reefs," she added.

"The effects of the atmosphere on light are pretty well known, but the challenge is to correct for the effects of the layer of water over the coral," Guild explained. "Instead of taking the top-down approach, we are going from the bottom up to the airplane, and later to satellite-sensing of coral health," Guild said.

"Ultimately, we plan to fly ’hyperspectral’ instruments, containing many detectors that collect information in the visible light range," Guild explained. These instruments will provide the most useful information about coral-reef community health from above the sea, according to Guild.

The team’s research emphasis is on Acropora palmata, or elkhorn coral, a major reef-building coral. It is prevalent in the study area, but is suffering from "white band disease." Elkhorn coral is on the verge of becoming an endangered species because it has severely declined in many areas of the Caribbean, Guild noted.

The team and engineering scientists from the University of Arizona also are developing a specialized computer model to analyze coral reflected-light data. The computer model will help scientists better interpret the raw data gathered by aircraft or satellites.

Guild will discuss her group’s work at the Fall Meeting of the American Geophysical Union on December 9, at 8:45 p.m. EST, in room 3000 of the Moscone Convention Center, San Francisco.

The research is funded by NASA’s Earth Science Enterprise, which is dedicated to understanding the Earth as an integrated system and applying Earth System Science to improve prediction of climate, weather and natural hazards using the unique vantage point of space.

John Bluck | GSFC
Further information:
http://www.gsfc.nasa.gov/topstory/2003/1200coral.html

More articles from Ecology, The Environment and Conservation:

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>