Nunavut’s Tundra Turns Red in Early September, NASA Satellites Capture Rapid Color Shift

NASA’s Landsat 9 satellite captured two images of the Coppermine River in Nunavut, Canada, showing a dramatic shift from green to vivid red, orange, and yellow between July 27 and September 6, 2026. Analysis of seven years of satellite data shows that tundra foliage begins to change in early September, peaks mid‑month, and then fades within a week or less—making Nunavut one of the first North American regions to display fall color. The color change occurs as chlorophyll breaks down when temperatures drop and daylight shortens, revealing carotenoids and anthocyanins that give leaves their yellow and red hues. Citizen scientists can now contribute to NASA’s long‑term environmental database by recording leaf color changes through the GLOBE North American Phenology Campaign, helping researchers track plant responses to climate shifts.