Climate Trend Analysis of Sea Surface Temperature, Water Vapor and Precipitation

This study is focused on the climate trend analysis of sea surface temperature (SST), water vapor (TPW) and precipitation during 1982-2008. The SST is from NOAA SST optimum interpolation (OI) products. Precipitation is from NASA global precipitation climatology project (GPCP) monthly products. Water vapor is estimated from the relationship between precipitable water and SST using the Clausius-Clapeyron relationship.

Results show a significant SST trend of 0.1115 °C/decade over the global ocean (74°S-64°N), however, a SST trend over the tropics (20°S-20°N) is not significant. The global mean TPW has a significant trend of 0.0183 g/cm^2/decade, while the trend of tropical mean TPW is not significant. The GPCP global mean and tropical mean oceanic rainfall has a significant trend of 0.0162 and 0.0461 mm/day/decade, respectively. Results also indicate a regional variation of the trend properties. The SST trend over the equatorial area (10°S-10°N) is not significant, but the trend is significant over the 30°N-50°, 10°N-30°N, 10°S-30°S, and 30°S-50°S zonal regions. Similar features are found for the TPW trend. However, the precipitation trend over these zonal regions is not significant, indicating a complex feature of precipitation trend. The impacts of the extreme events (El Nino, La Nina) on the climate trend are also analyzed. Results indicate these events intensify the trend magnitudes. The horizontal distributions of the climate trends present a complex feature of SST, TPW and precipitation on the trend analysis, suggesting a special attention should be paid to the regions applied in the climate-related studies.