AERONET in South America
A sensor has been located at the Laser and Applications Center, a research institute devoted to measuring and monitoring the atmosphere using lasers. Their instruments measure the atmosphere from the ground, providing data that is used to, among other things, calibrate satellite images such as this one.
The sensor is part of the AErosol RObotic NETwork (AERONET) a consortium of researchers committed to sharing their data and information for the benefit of science.
Satellite images are formed by recording the amount of solar radiation (sunlight) that travels through the atmosphere, is reflected off of the Earth's surface, and transmitted back through the atmosphere to the sensor. Therefore, understanding how solar radiation reacts to things in the atmosphere like water vapor, smoke or dust is critical for the creation of accurate satellite measurements of the Earth's surface.
Sensors such as this one are located throughout the globe, on every continent. This particular sensor is located near the River Plate, at the confluence of the rivers Uruguay and Parana in the Southeastern portion of South America.
The River Plate, or Rio de la Plata in Spanish, is the widest river in the world, stretching 220 kilometers (136 miles) where it meets the Atlantic Ocean. This broad, flat estuary separates Argentina and Uruguay and is home to the ports of Buenos Aires and Montevideo, their respective capital cities. The tan-brown patch towards the bottom of the image is sediment carried by the river; it is a hazard to navigation and must be dredged periodically in order to keep the port of Buenos Aires open for shipping.