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 Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

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: Making Waves

Computer scientists use wave packet theory to develop realistic, detailed water wave simulations in real time. Their results will be presented at this year’s SIGGRAPH conference.

Think about the last time you were at a lake, river, or the ocean. Remember the ripples of the water, the waves crashing against the rocks, the wake following...

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Nanostructures taste the rainbow

29.06.2017 | Physics and Astronomy

New technique unveils 'matrix' inside tissues and tumors

29.06.2017 | Life Sciences

Cystic fibrosis alters the structure of mucus in airways

29.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>