Abstract
Many studies have shown a growing trend in terms of frequency and severity of extreme events. As never before, having tools capable to monitor the amount of rain that reaches the Earth’s surface has become a key point for the identification of areas potentially affected by floods. In order to guarantee an almost global spatial coverage, NASA Global Precipitation Measurement (GPM) IMERG products proved to be the most appropriate source of information for precipitation retrievement by satellite. This study is aimed at defining the IMERG accuracy in representing extreme rainfall events for varying time aggregation intervals. This is performed by comparing the IMERG data with the rain gauge ones. The outcomes demonstrate that precipitation satellite data guarantee good results when the rainfall aggregation interval is equal to or greater than 12 h. More specifically, a 24-h aggregation interval ensures a probability of detection (defined as the number of hits divided by the total number of observed events) greater than 80%. The outcomes of this analysis supported the development of the updated version of the ITHACA Extreme Rainfall Detection System (ERDS: erds.ithacaweb.org). This system is now able to provide near real-time alerts about extreme rainfall events using a threshold methodology based on the mean annual precipitation.
Highlights
According to the IPCC (Intergovernmental Panel on Climate Change), “an extreme weather event is an event that is rare at a particular place and time of year
In order to face this problem on a global scale, it is necessary to work with data acquired on a continuous basis and made available in real time
The temporal series of no data cells contained in every half-hourly Global Precipitation Measurement (GPM) IMERG product was analyzed
Summary
According to the IPCC (Intergovernmental Panel on Climate Change), “an extreme weather event is an event that is rare at a particular place and time of year. Definitions of rare vary, but an extreme weather event would normally be as rare as or rarer than the 10th or 90th percentile of a probability density function estimated from observations. The characteristics of what is called extreme weather may vary from place to place in an absolute sense” [1]. The main feature concerns the possibility of carrying out a measurement on huge areas of the Earth’s surface (satellites have a more extensive coverage compared to other instruments). For this reason, in the last decades, a great effort has been made to improve the precipitation measurement by satellite data
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call