How green is my planet?
点击量： 时间：2019-02-26 09:18:01
A SATELLITE is sending back spectacular images of plant life on Earth. The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) monitors the absorption of light by chlorophyll, used in photosynthesis. The main goal of the SeaWiFS mission, sponsored by NASA, is to measure populations of microscopic marine plants called phytoplankton. But when the satellite began beaming back data last month, it turned out that the sensor was powerful enough to see land plants as well. “We’re really pleased with these results,” says SeaWiFS project manager Mary Cleave. In this image, high concentrations of plant life are shown as yellow or green, while low densities are blue. The team hopes that the satellite data will help in predictions of climate change, for example that caused by El Niño—the warming of Pacific waters that occurs every few years. Phytoplankton populations increase as the oceans heat up. The data will also allow marine biologists to monitor the spread of toxic algal blooms,