Assimilation and Direct Insertion of Sentinel Products in the WRF Weather Forecast Model

Abstract

In the framework of the E-SHAPE EuroGEOSS Showcase: Applications powered by Europe project, one of the pilot applications concerns the disasters in urban environment. One of the objectives of this application is the conceiving of innovative services for extreme-scale hydro-meteorological modelling that make use of Copernicus Earth Observation data. An example of innovative service is the ingestion of high-resolution Copernicus remote sensing products in numerical weather prediction (NWP) models. The rationale is that NWP models are presently able to produce forecasts with a spatial resolution in the order of 1 km, but unreliable surface information or poor knowledge of the initial state of the atmosphere may imply an inaccurate simulation of the weather phenomena. It is expected that forecast inaccuracies could be reduced by ingesting high resolution Earth Observation products into the models. In this context, the Copernicus Sentinel satellites represent an important source of data, because they can provide a set of high-resolution observations of physical variables (e.g. soil moisture, land/sea surface temperature, wind speed over sea, columnar water vapor) used in NWP model runs. The possible availability of a spatially dense network of Global Navigation Satellite Systems (GNSS) stations could also be exploited to allow NWP models to assimilate timely updated data about water vapor in the atmosphere. As a preliminary activity carried out in the frame of the E-SHAPE project, this paper presents the results of the experiments regarding the insertion/assimilation of surface information derived from Sentinel data into a NWP model. The experiments concern a flood event occurred in Italy in 2017 that affected an urban area, namely the Livorno city.