An investigation of remotely sensed precipitation products over Puerto Rico

Puerto Rico’s climatology is tropical marine with the rainy season from April through November and August with the highest rainfall totals. There is a large variation of rainfall across the island. Given the availability of remotely sensed observations of rainfall over this location, we investigate precipitation estimates from NOAA’s climate data records (CDRs) and National Weather Service (NWS) precipitation estimates, mainly the NWS Stage IV.

We use CDRs that are based on satellite observations from the Global Precipitation Climatology Project (GPCP), Climate Prediction Center (CPC) Morphing Technique (MORPH) (CMORPH), and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN). In addition, we use ground based remotely sensed observations that are based on the NEXRAD radar observations, namely the NWS Stage IV precipitation estimates.

In this study we attempt to compare and evaluate the different precipitation observations that have different spatial and temporal resolutions. The CDRs are provided at the daily resolution and mainly in the 0.25 degree spatial resolution. The NWS Stage IV is provided at the daily and hourly resolution at the 4km degree spatial resolution. Given the varying resolutions of data we will be able to investigate across resolutions from coarse to finer resolution. We expect that by looking at the finer details of these resolutions we should be able to come to some conclusions about the highly variable precipitation across the island – with a focus on higher rainfall totals as they relate to extreme events.