How environmental conditions influence satellite detection of rainfall events

Precipitation serves as a critical link between climate and hydrology, with variability shaped by environmental factors that regulate satellite detection under complex conditions. Physical response mechanisms under varying temperature, soil moisture, and pressure remain insufficiently assessed. Using global gauge precipitation and ERA5-Land reanalysis data, we identified HIT, MISS, FALSE events and examined their differential responses to key environmental variables. We demonstrate that HIT events tend to occur under intermediate environmental conditions, with both products sharing similar responses but GSMaP exhibiting slightly smoother temperature signals and IMERG stronger soil-moisture-related variability. MISS events, linked to colder, wetter backgrounds, are associated with larger spread, while FALSE events arise mainly in warm, dry regimes with low soil moisture and more fluctuations in IMERG. Environmental factors modulate detection, with warmer and wetter conditions favoring HIT and suppressing FALSE, while pressure plays a weaker, secondary role. These findings support satellite-based global hydrology and climate-resilience assessment.