EGUsphere

Copernicus Publications

Göttingen, Germany

10.5194/egusphere-2026-1234

Influence of Sea Surface Temperature on the Columnar Water Vapor Content and Cloud Fraction, Based on Monthly-Averaged MODIS Data at 1° by 1° Resolution

Park

Jung Eun

¹ Lee

Taewoo

Mechanical and Aerospace Engineering, SEMTE, Arizona State University, Tempe, AZ, USA

10 06 2026

2026 1 16

2026

This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/

This article is available from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-1234/

The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-1234/egusphere-2026-1234.pdf

Satellite data on global sea surface temperature (SST), water vapor and cloud fraction are analyzed to provide direct relationships on these parameters. Increase in SST elevates the water vapor pressure at the surface following the Clausius-Clayperon (exponential) form, and this effect persists to increase the columnar water vapor up to SST of approximately 300 K, at the 1° by 1°, monthly-averaged scale. Beyond SST of 300 K, a steeper slope for the columnar water vapor is observed. A similar transitional relationship is observed between cloud fraction (CF) and SST, except that a negative slope is found up to SST of 300 K. Then, a reversal occurs at SST of approximately 300 K where CF increases quadratically as a function of SST. Parameterization of water vapor and CF is provided as a function of SST for 1° by 1° spatial resolution and monthly-averaged time scale.