Last update: November 12th, 2019 at 11:00 am
Sometimes nature puts on a spectacular show, dazzling us with unusual displays of color or whimsical patterns. On November 5, 2009, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite caught one such display. A pale brown plume of dust swept out of Argentina’s Pampas, a heavily farmed grassland, and split into two plumes over the South Atlantic Ocean. The wide arc and subtle curls within the dust plume complement the patterns visible in the ocean beneath it.
Peacock-colored, the South Atlantic Ocean was in full bloom: A display of blue and green streaks and swirls peek from beneath the dust storm. Cool currents and upwelling water along the edge of the continental shelf bring nutrient-rich water to the surface off the coast of northern Argentina. As a result, tiny plant-like organisms, phytoplankton, thrive in this part of the South Atlantic Ocean.
The wind-blown dust also carries iron and other nutrients that fertilize already fertile ocean waters. The surface-dwelling phytoplankton color the ocean, contributing to the brilliant color seen in the image. Sediment from the Rio de la Plata may also be contributing to the ocean color. The southern edge of the brown, sediment-filled estuary is visible along the top of the image. Like dust, sediment from river plumes also adds nutrients to the ocean, further supporting phytoplankton blooms.
The transition from ocean bloom to airborne dust blurs along the north side of the dust plume. A murky green ribbon of plankton or sediment winds north-south on the surface of the ocean from beneath the clouds to the dust plume. The green-brown band of color continues to be visible beneath the dust plume, but its color blends with the dust, making it appear as if the ocean is projecting its color into the sky.
Credit: NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team at NASA GSFC. Caption by Holli Riebeek, NASA Earth Observatory.