Diurnal Variation of Liquid Water Path Derived From Two Polar‐Orbiting FengYun‐3 MicroWave Radiation Imagers

MicroWave Radiation Imagers (MWRIs) onboard the afternoon FengYun‐3B (FY‐3B) and midmorning FengYun‐3C (FY‐3C) satellites provide global observations almost 4 times a day at any location. This study examines the diurnal cycle of the liquid water path (LWP) over the southeast Pacific Ocean using MWRI data. A double‐difference calibration method is first used to evaluate the MWRI calibration bias based on Tropical Rainfall Measuring Mission Microwave Imager (TMI) measurements. LWP diurnal cycle characteristics are derived from FY‐3B/C MWRI data measured in 2014. The diurnal variation of LWP from combined FY‐3B/C MWRI measurements are consistent with that derived from Tropical Rainfall Measuring Mission Microwave Imager data. Maximum and minimum LWPs occurred in the early morning and afternoon, respectively. The largest diurnal amplitude (~40% of the mean LWP) was located near 85°W/20°S. The diurnal amplitude varied from season to season. MWRI data can provide important constraints for models simulating the cloud diurnal cycle.