Fig. 9From: Morphology of sporadic E layers derived from Fengyun-3C GPS radio occultation measurementsSeasonal variation in the latitude–local time distributions of FY-3C RO-derived Es occurrence rates for the two local time periods, 9:00–11:00 LT and 21:00–23:00 LT, during Jan. 2015 to Dec. 2019, with a resolution of 5° latitude × 1 h. Plots for four different seasons a MAM, b JJA, c SON, and d DJFBack to article page