Weather Prediction

Coral reefs may even contain some secrets about our past. Researchers at Texas A&M are exploring ways to use coral as permanent record keepers. And what coral can tell us about past climatic conditions may help us predict changes in our weather in the future.

Scientists first inspect coral colonies for the right specimen. Then using a hydraulic drilling system, divers extract cylindrical cores. Many of the core samples measured more than five feet long. They are taken in, sectioned and reassembled on the boat.

After the sections are examined, they are wrapped and labeled before being transported to the laboratory for further study. Researchers will conduct extensive tests on the coral samples at Texas A&M University laboratories.

The coral core is then cut with a saw blade and a slab of coral is taken from the coral core. Researchers then X-ray this coral slab and make positive prints of the X-ray. The X-ray reveals a lot of detail that isn't visible with the naked eye. A series of bands is clearly visible; each band represents a different year. Researchers start at the top of the coral core and count each band down towards the bottom and use that to determine the age of the corals and to determine the ages of individual bands of material.

Each annual band is chemically tested. The cores provide a record of temperature and salinity over the past 200 or more years. Scientists believe that the corals at the Flower Gardens go back at least about 250 years.

But why does any of this matter and how can we use the information?

The coral cores provide a record of previous events that are comparable to what's going on right now in the atmosphere, environmental change and global warming. Researchers hope that by knowing what's happened in the past, they can more easily predict what might happen in the future, by monitoring those variables in the marine environment.

Studying coral, scientists also hope to gain insight into the economic impacts of climate change of the region; historically how has the climate changed and then relate that to economic changes.

For example, fisheries are severely affected by what goes on, on land. Rainfall patterns, for example, drastically affect shrimp harvests in following years. Corals have recorded what the effects have probably been on those harvests in the past several hundred years. And scientists can see that now by analyzing the details of the coral growth rings they have gotten in these cores. They will be able to better predict, in the future, the effects of climate change on the harvest of commercially important species. And the coral will basically give the basis on which to make those predictions.

Global warming researchers are also looking to the Flower Gardens with hopes of understanding the effects of global warming on corals around the world. Even though corals thrive in warm, clear, tropical waters they are sensitive to changes in water temperatures. Water temperatures in certain areas have warmed to damaging levels. Some scientists believe higher temperatures are causing a decline in coral reef growth.

Scientists plan to use the Gardens as a control gauge to better understand those other corals, because the Flower Gardens seem to be relatively healthy. They will compare the histories of other reefs to the Flower Garden's histories. And since the Flower Gardens are still healthy, and researchers can reconstruct records of the temperature, and possibly pollutants, they will use that to better understand what's hurting reefs in Florida and in other areas.

The corals at the Flower Gardens are very sensitive to changes in the climate because they are living just on the edge of their natural environmental conditions. That means that scientists can more clearly see changes there. And that makes the Flower Gardens an ideal place for research.