GEO - High Resolution Winds
Javier Garcia-Pereda and Mate Mile give an overview on the NWC-SAF high resolution wind product and its application.
The “NWC SAF/HRW High Resolution Winds” provides a detailed calculation of Atmospheric Motion Vectors locally and in near real time. It calculates the AMVs considering cloud and humidity patterns in up to seven different MSG/SEVIRI channels (HRVIS, VIS06, VIS08, WV062, WV073, IR108, IR120), together with NWP data and the “NWC SAF Cloud products (Cloud type, Cloud top temperature and height)”.
It considers up to two tracer scales (Basic and detailed), two tracer determination methods (Gradient and tracer characteristics), two tracking methods (Euclidean distance or cross correlation), and two Height level assignment methods (Brightness temperature interpolation method and Cross correlation contribution method). As other AMV products worldwide it also includes a quality control flagging based on the Quality Indicator Method developed at EUMETSAT.
NWC SAF/HRW product can be useful in Nowcasting applications in synergy with other data available to the forecaster: monitoring of low level convergence, divergence at the top of developed systems, or other cases of small scale circulation or wind singularities. It can also be used as an input in analysis and forecasting applications like NWP models. The development and main characteristics of the product are explained with examples, useful for the potential users to know what the product can offer. The validation results related to the latest version on the product (HRW v4.0) are also explained.
The role of the Atmospheric Motion Vectors (AMV) in the modern data assimilation systems is evident nowadays. The AMVs – along with satellite observations – have an important key for our operational ALADIN data assimilation system as well. In the framework of the EUMETSAT SAF High Resolution Winds (HRW) products had been developed by AEMET for Nowcasting and Very Short Range Forecasting purposes. The HRW products provide quasi real time data of AMVs from MSG HRVIS and IR10.8 channels every hour in a day. A collaboration between AEMET and OMSZ have been focused to compare the benefit of the operationally used AMVs (received through the EumetCAST) with the newly processed HRW winds. Recent work was an extensive evaluation and monitoring of the assimilation and forecast system. The impact of the AMV winds was examined using different diagnostic techniques, verifications tools and case studies. The first results are promising regarding the use of the HRW AMV. The statistical scores on the full domain showed neutral or slightly positive impact in most of the parameters and the experiment based on HRW AMV data provided better estimate of extreme precipitation events.