undef

s1b-ew-grd-hv-20170526t152209-20170526t152313-005771-00a1d8-002_filter

s1b-ew-grd-hh-20170526t152209-20170526t152313-005771-00a1d8-001_filter

s1b-ew-grd-hh-20170526t152209-20170526t152313-005771-00a1d8-001_winddir

s1b-ew-grd-hv-20170526t152209-20170526t152313-005771-00a1d8-002_winddir