undef

s1a-ew-grd-vv-20160903t051934-20160903t052034-012884-0145a7-001_filter

s1a-ew-grd-vh-20160903t051934-20160903t052034-012884-0145a7-002_filter

s1a-ew-grd-vh-20160903t051934-20160903t052034-012884-0145a7-002_winddir

s1a-ew-grd-vv-20160903t051934-20160903t052034-012884-0145a7-001_winddir