Source: USGS
A quote to note from Wulder on looking at historic land cover change:
“Anything that’s historic, it’s got to be Landsat. In temporal depth, Landsat is really the only game in town.”

Above the Earth, Below the Surface: Landsat’s Role in Monitoring Water Quality
Safeguarding freshwater resources is crucial, and while scientists use a variety of ground-based techniques to gauge water quality, the Landsat program has provided water quality data from orbit for decades.