Douglas_2011 NWC_MODIS_seminarmod1
Dec 21, 2011Public
Photo: NWC talk in October 2011 or thereabouts...
Photo: justification for this work - since not closely related to NSSL mission
Photo:
Photo:
Photo:
Photo: GOES nominally 1km at nadir but satellite wobble smears data - most recent GOES much better than earlier ones.
Photo:
Photo:
Photo:
Photo: lowering the cloud detection threshold value gets you more clouds but at cost of detecting bright land areas (pure white = 255).  Thin clouds in circle detected only when threshold was lowered to 120.
Photo: cloud amount detected depends on threshold you select
Photo:
Photo:
Photo: 3 month averages of cloudiness from MODIS using our technique (top) and NASA cloudmask product (bottom).  Note many artifacts in NASA product (flags as contaminated many surfaces that are due to agriculture)
Photo: Florida, Sinaloa coastal plain, most cities show artifacts.
Photo: NAM 18hr cloudiness forecasts averaged for 3 mos.
Photo: not too bad an agreement
Photo: diurnal changes not quite the same - florida diurnal tendencies more obvious in MODIS than NAM.
Photo:
Photo: where is this?  hard to tell with too coarse a spatial resolution.
Photo: We are in Mexico...
Photo: easier now but still not perfect
Photo: OK...at full resolution we can now see cloudiness and how it is related to topography.
Photo: