Rainy Days in Death Valley
It doesn't take much rain to fill the compressed, silty sediments found in Death Valley, CA. At 282 feet below sea level, Death Valley in the lowest point in North America. It is also notable as one of the driest places on the continent, but rains do fall from time to time. More than an inch of rain fell in the mountains west of Furnace Creek over two days in early March 2019 – more than triple the typical amount for the month.
Landsat imagery captured less than a week after the rains shows the standing water and saturated sediment that remained.
The first image, from March 24, 2018, shows Death Valley in a more typical spring. Band 1 of the satellite's Operational Land Imager is known as the "Ultra Blue," or coastal/aerosol band, and is especially sensitive to shallow water. Combining bands 7, 5, and 1 to create the first image renders the basin's shallow pools of saltwater in a light aqua color.
In the March 11, 2019 image, the same band combination highlights streaks of aqua that are deeper and extend further, with standing water appearing nearly black in long stretches running north to south.
Landsat imagery is useful for capturing the impact of weather-related anomalies on the landscape, but also for establishing trends. The Landsat archive represents the longest continuously collected, moderate resolution record of the Earth's surface.