A forest 'glow' reveals awakening from hibernation

Gross Primary Production (GPP) in forests tells scientists how much CO2 these vast and remote systems are breathing in. For decades, scientists have used satellites to monitor the changes in greenness of deciduous forests to track GPP. Evergreen trees, however, retain their green needles year round, preventing scientists from detecting photosynthesis cycles on large scales. A new study is the first to link GPP with solar-induced fluorescence in evergreens, which can be tracked by satellites.
Source: EurekaAlert, https://www.eurekalert.org