Based on the OSI SAF cone visualisation tools at KNMI and the NOC corrections, calibration of the ASCAT scatterometer is checked. In this report we describe and evaluate level 1b corrections to the operational L1b ASCAT backscatter data version PPF740 as provided by EUMETSAT based on their three transponder calibration campaign. For the left mid antenna an offset in ocean calibration results ha...

Kolmogorov second-order structure functions are used to quantify and compare the small-scale information contained in near-surface ocean wind products derived from measurements by ASCAT on MetOp-A and SeaWinds on QuikSCAT. Two ASCAT and three SeaWinds products are compared in nine regions (classified as rainy or dry) in the tropical Pacific between 10 S and 10 N and 140 and 260 E for the period...

A new scatterometer, the so-called Advanced scatterometer (ASCAT), onboard MetOp-A satellite was successfully launched on October 19 2006. During the commissioning phase one of the main goals is to accurately calibrate the instrument. The radar backscatter has been calibrated using three groundbased transponders only in February 2008. However, stable and good quality ASCAT winds are produced ro...

Remotely sensed soil moisture products derived from the Advanced SCATterometer (ASCAT) and from the Soil Moisture and Ocean Salinity (SMOS) radiometer are analyzed and compared. The comparison has been carried out within the framework of an activity aiming at validating the EUMETSAT Hydrology Satellite Application Facility (H-SAF) soil moisture products derived from ASCAT over Europe and North ...

Scatterometer data are known to improve the quality of surface winds over the ocean. In particular Cband scatterometers, thanks to the microwave wavelength used, are capable of providing information also in the presence of rainfall. Their observations are therefore important for the analysis of winds in case of extreme events. C-band scatterometers have been assimilated into the European Centre...

Introduction satellite based scatterometers provide high resolution all-weather wind vector fields over the seas. Wind speed and wind direction are provided at high accuracy under all weather conditions. The allweather EsA ERs scatterometer observations have proven its significant impact for the forecasting of fast developing and severe weather. Moreover, scatterometer wind fields are provided ...

Using accurate inputs of wind speed is crucial in wind resource assessment, as predicted power is proportional to the wind speed cubed. This study outlines a methodology for combining multiple ocean satellite winds and winds from WRF simulations in order to acquire the accurate reconstructed offshore winds which can be used for offshore wind resource assessment. First, wind speeds retrieved fro...

The SMOSMANIA soil moisture network in Southwestern France is used to evaluate modelled and remotely sensed soil moisture products. The surface soil moisture (SSM) measured in situ at 5 cm permits to evaluate SSM from the SIM operational hydrometeorological model of Météo-France and to perform a cross-evaluation of the normalised SSM estimates derived from coarse-resolution (25 km) active micro...

A long term data acquisition effort of profile soil moisture is currently underway at 13 automatic weather stations located in southwestern France. In this study, the soil moisture measured in-situ at 5 cm is used to evaluate the normalised surface soil moisture (SSM) estimates derived from coarse-resolution (25 km) active microwave data of the ASCAT 5 scatterometer instrument (onboard METOP), ...

This project aims to investigate the quality of ASCAT measurements as well as their use for oceanographic purposes. The accuracy of ASCAT retrievals will be mainly based on the use of collocated data from moored buoys, numerical weather prediction models, and satellites. The resulting collocated data will be used to explore the accuracy of the geophysical model function which relates the backsc...