Green leaves are abundant with chlorophyll, which is necessary for photosynthesis. Plants, trees, and cyanobacteria use photosynthesis to turn sunlight into sugars, while also producing oxygen as a byproduct. But chlorophyll is not the only pigment found in these organisms. Other pigments, like carotenoids and anthocyanins, also aid photosynthesis and provide protection against stressors like heat or too much sunlight. Unlike green chlorophylls, carotenoids are orange and yellow. Anthocyanins are red, blue, or purple. Combinations of these pigments yield the vibrant array of color we see in flowers and fruits.
And now, scientists are using satellites to take global measurements of these pigments every one to two days.
NASA’s Plankton Aerosol Cloud ocean Ecosystem (PACE) satellite launched in 2024. Designed to observe the color and biology of the ocean, as well as atmospheric variables related to air quality, PACE’s data collection extends over land areas, too.
The animated map above from NASA’s Scientific Visualization Studio (SVS) shows a year of data collected by PACE between March 2024 and March 2025. An array of color represents the type and relative composition of the pigments observed in plant life over that time. Chlorophyll is shown in green, blue represents carotenoids, and anthocyanins are mapped in red. Areas with high quantities of all pigments are shown in brighter colors, ultimately blending to white.
As the animation plays, you can see how pigments of all types begin to move northward as spring and summer make their way to the northern hemisphere. The colors gradually shift south again toward the end of the video as the seasons change. Some types of trees and plants undergo more seasonal changes than others, revealed by a transformation in color over an area through time. The northern boreal forest undergoes a large shift through pigment types, indicating changes in growth and stress throughout the seasons. In contrast, areas like the Australian Outback and central Africa are dominated by fewer pigment types throughout the year.
PACE is equipped with an Ocean Color Instrument (OCI) and two polarimeters, the Spectro-polarimeter for Planetary Exploration (SPEXone) and the Hyper Angular Research Polarimeter (HARP2). The satellite orbits at an altitude of 676.5 kilometers (420 miles). These instruments have a minimum mission duration of three years, though they can be maintained to support operations for ten years. It is common for NASA’s satellites to operate long beyond the scope of their original missions.
