The Red in a NASA Scientist's Foliage Maps Is Not Always Autumn
NASA data scientist Skye Caplan has been posting weekly maps of vegetation redness for the GLOBE program's North American Phenology Campaign. The maps show waves of red appearing in the high latitudes in August and shifting equatorward through September and October.
Caplan said pigment changes can also occur when vegetation is stressed by drought or insect damage. She noted that changes like these likely help explain the high redness measured in agricultural regions of Brazil, Australia and Canada that do not track closely with the broader seasonal shift.
AI-generated discussion · Different perspectives
Any index has this problem: it measures what it measures, and the name supplies the rest. Redness is a pigment signal; autumn is the caption we add.
Only if you insist the map is a foliage forecast. If drought and insect damage move the same signal, a red patch that isn't autumn is a feature, not a flaw.