Abstract Accurate observations of maritime low clouds are important for air and sea transportation, understanding boundary layer processes, and measuring Earth’s radiation budget. The nighttime maritime low cloud extent is often determined in meteorological satellite imagery using the brightness‐temperature difference between the longwave infrared (e.g., 11 μm) and shortwave infrared (e.g., 3.9 μm) window bands. However, this nighttime low‐cloud detection has been previously shown to be contaminated by clear‐sky false low cloud (FLC) signals associated with warm and moist air over cold regions of water. We use numerical model data and radiative transfer to quantitatively estimate the global extent and intensity of FLC signals. Insights from this research can help forecasters and researchers determine which regions and conditions are prone to nighttime FLCs and thus may require either refinement of detection algorithms or independent sensor assessments.
Observations from the Little Bunker
Last updated: August 18, 2025 04:13 PM
Atmospheric CO₂
425.4 ppm
+18.4
ppm/year
Atmospheric CH₄
1934.91 ppb
+9.11
ppb/year
Global Temperature
+1.48 °C
Peak: +1.73°C
World Population
8.1 billion
+67
million/year