It has been observed that the skeletal coral structures of the Great Barrier Reef exhibit yellow-green fluorescent bands reflecting centuries of rainfall and coastal runoff. These bands are found only on the inner shelf reefs within 20 km of shore, and exhibit a strong correlation with the timing, duration, and intensity of summer and monsoonal rainfall, as well as coastal runoff in general. Therefore, these bands can be analyzed to create trend lines in precipitation and runoff data so as to extrapolate historical patterns and estimate projected rainfall.
In addition to being used for simple meteorological applications, the chemical makeup of these bands may also be examined for traces of harmful compounds. This way, if it is evident that runoff from the nearshore terrestrial environment contains pollutants and any other unnatural products, regulations can be enacted to prohibit the use of such substances in coastal areas to ensure the vitality of the reef ecosystem and its biodiversity.
-by Caroline Greenwood
Isdale, P. 1984. Fluorescent bands in massive corals record centuries of coastal rainfall. Nature, 310(5978), 578-579.