Fig. 3

Illustration of the number of cloud-free Landsat measurements used in the WUS–SR for four WYs (top four panels) and Landsat mission timelines (bottom panel). Landsat images with diagnosed cloud fractions of 40% are excluded entirely and those will less than 40% use the Landsat cloud mask to screen out cloudy measurements. The four illustrative WYs include: (a) WY 1992 and (c) 2012 when one Landsat satellite is in orbit, and (b) WY 2002 and (d) 2018 when two Landsat satellites are in orbit. The stripes showing a larger number of measurements are the overlapping areas between adjacent Landsat tiles. The temporal coverage of measurements in (e) shows the Landsat 5, 7 and 8 mission timelines. Periods with only one Landsat satellite are shaded with a gray background. The orange hatched areas indicate the four WYs present in maps in the top panels.