Satellites used to measure photosynthesis

Satellite technology has been used to measure the light that plant leaves emit as a byproduct of photosynthesis.

The satellite senses the light, called fluorescence, as it passes overhead.

It provides a tool to help evaluate agricultural productivity, and a way to assess uncultivated forests and grasslands.

Researcher Joe Berry, from Carnegie Institution for Science, said this is the first time photosynthesis has been directly observed on a large scale.

Other approaches use model-based estimates to detect large-scale photosynthetic activity. These approaches are indirect and their accuracies have been difficult to evaluate.