The above image is of Death Valley in California, showing the change from March of 2018 (the before image) to March of 2019 (the after image).
NASA explains, “Death Valley is one of the driest places in North America. A typical March sees about a third of an inch (about 8 millimeters) of rain. The 2018 image shows the mountains west of Furnace Creek as the area usually appears during that time of year. Saturated sediment and shallow pools of water are displayed in a light aqua color. The 2019 image shows the same area less than a week after it received more than an inch of rain in just two days. The deeper pools that resulted appear nearly black.”
Sources:
“Rain in Death Valley, California.” NASA, NASA, https://climate.nasa.gov/images-of-change?id=691#691-rain-in-death-valley-california.