A satellite-based high-resolution offshore wind archive for mesoscale comparison for the New European Wind Atlas

Ahsbahs, T. T. (Guest lecturer), Badger, M. (Guest lecturer), Hasager, C. B. (Guest lecturer), Karagali, I. (Guest lecturer), Hahmann, A. N. (Guest lecturer), Tija Sile (Guest lecturer), Mann, J. (Guest lecturer)

Activity: Talks and presentationsConference presentations

Description

The New European Wind Atlas (NEWA) aims to provide a high-resolution wind atlas based on 30 years of mesoscale model runs from the Weather Research and Forecasting (WRF) model. Validation of the mesoscale model is necessary to confirm its accuracy across Europe. For onshore locations this is done with long time series of in situ observations and data from new field experiments. This presentation focuses on using high resolution wind fields derived from satellite measurements for validation offshore where in situ data is scarcer.
Data from two instrument types are used: scatterometer and Synthetic Aperture Radar (SAR). Scatterometers are designated for ocean wind observations with a resolution of typically 25 km. Satellites carrying SAR systems are not designed for wind observations, but wind fields can be derived at 0.5 km resolution. SAR wind fields are most useful where high spatial resolution is necessary, for example, close to shore (1 km to 50 km). Initial comparisons of preliminary NEWA model runs with mean wind speeds based on both data types suggest that the spatial distribution of mean wind speeds is similar1.
We will present an archive of high-resolution wind fields from SAR. The SAR wind fields are reprocessed solving three challenges: 1) Inconsistent model inputs resolved by using ERA5 for wind direction inputs. 2) Correction of time varying biases of the wind speed for different sensors. 3) Filtering of erroneous high wind speeds resulting from ships and other man-made structures. An archive using data from three European satellites Envisat, Sentinel-1A, and Sentinel-1B covering the years from 2002 to 2018 will be created.
The new SAR wind archive is used to create an observation-based wind atlas over the European Seas. Comparisons to mesoscale models will focus on coastal mean wind speed gradients and terrain-induced high wind speed phenomena, e.g. gap flows or low-level coastal jets.
Period17 Jun 2019 - 20 Jun 2019
Held atWind Energy Science Conference 2019
Event typeConference
LocationCork, Ireland
Degree of RecognitionInternational

Keywords

  • offshore
  • satellite wind
  • synthetic aperture radar
  • validation
  • Wind Atlas