Changes in extreme precipitation patterns over the greater Caribbean and teleconnection with large-scale sea surface temperature

Abstract. This study examines changes in extreme precipitation over the greater Caribbean and their correlation with large-scale sea surface temperature (SST) for the period 1985 to 2015. The data used for this study were derived from two satellite products: Climate Hazards Group InfraRed Precipitation (CHIRPS) and NOAA DOISST (Daily Optimum Interpolation Sea Surface Temperature version 2.1) with resolutions of 5 km and 25 km, respectively. Then, change in the characteristics of six(6) extreme precipitation indices defined by the WMO ETCCDI (World Meteorological Organization Expert Team on Climate Change Detection and Indices) is analyzed, and Spearman's correlation coefficient has been used and evaluated by t-test to investigate the influence of a few large-scale SST indices: (i) Caribbean Sea Surface Temperature (SST-CAR); (ii) Tropical South Atlantic (TSA); (iii) Southern Oscillation Index (SOI); (iv) Northern Oscillation Index (NAO). The results show that at the regional scale, +NAO contributes significantly to a decrease in heavy precipitation (R95p), daily precipitation intensity (SDII), and total precipitation (PRCPTOT), whereas +TSA is associated with a significant increase in daily precipitation intensity (SDII). At an island scale, in Puerto Rico and southern Cuba, the positive phase of +TSA, +SOI, and +SST-CAR is associated with an increase in daily precipitation intensity (SDII) and heavy precipitation (R95p). However, in Jamaica and northern Haiti, the positive phases of +SST-CAR and +TSA are also associated with increased indices (SDII, R95p). In addition, the SST warming of the Caribbean Sea surface temperature and the positive phase of the Southern Oscillation (+SOI) significantly increases with the number of rainy days (RR1) and the maximum duration of consecutive rainy days (CWD) over the Dominican Republic and in southern Haiti.