On May 10, 2021, the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Aqua satellite acquired a true-color image of a sunny day over southeastern Europe.
Glorious deep greens mark forested land, while agricultural fields with open soil, ripe for planting, appear tan. Early crops color the fields light green. Bits of snow sit atop the high peaks of the Carpathian Mountains in Romania and western Ukraine and, further south, across the Balkan Mountains of Bulgaria.
Swirls of phytoplankton stain inky blue waters of the Black Sea. These microscopic organisms live in these waters year-round in small numbers and, when nutrient load, water temperature, and length of sunshine are just right reproduce explosively, creating large blooms that can be seen from space. Some of the swirling color may also be from suspended sediment.