Until now, scientists have only had a continuous record of photosynthesis on land. But following three years of continual data collected by the SeaWiFS instrument, NASA has gathered the first record of photosynthetic productivity in the oceans. By taking three years of continuous data as a whole, experts have been able to map trends and anomalies in the global circulation of carbon to a degree of detail than has never been done before. It is a baseline measurement to by which all future measurements will be compared.