Diurnal Ocean Surface Layer Model Validation

• Main Authors: Hawkins, Jeffrey D., May, Douglas A., Abell, Jr, Fred
• Other Authors: NAVAL OCEANOGRAPHIC AND ATMOSPHERIC RESEARCH LAB STENNIS SPACE CENTER MS
• Format: Text
• Language: English
• Published: 1990
• Subjects: Physical and Dynamic Oceanography; Optics; *OCEAN MODELS; *SEA WATER; *SURFACE TEMPERATURE; *FORECASTING; *DIURNAL VARIATIONS; *OCEAN SURFACE; OBSERVATION; WIND; HIGH RESOLUTION; SURFACES; CASE STUDIES; INFRARED IMAGES; HEATING; IMAGES; DUCTS; ARTIFICIAL SATELLITES; ACOUSTICS; MIXING; NIGHT; INFRARED RADIATION; NORTH ATLANTIC OCEAN; MULTICHANNEL; SUBTROPICAL REGIONS; HIGH SENSITIVITY; SATELLITE PHOTOGRAPHY; ACOUSTIC WAVES; LAYERS; GLOBAL; SPATIAL DISTRIBUTION; ACOUSTIC CHANNELS; THERMAL PROPERTIES; PROPAGATION; WUDN394457; PE63704N; North Atlantic
• Online Access: http://www.dtic.mil/docs/citations/ADA229010; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA229010

The Diurnal Ocean Surface Layer (DOSL) model at the Fleet Numerical Oceanography Center forecasts the 24-hour change in a global sea surface temperatures (SSt). Validating the DOSL model is a difficult task due to the huge areas involved and the lack of in situ measurements. Therefore, this report details the use of satellite infrared multichannel SST imagery provide day and night SSTs that can be directly compared to DOSL products. This water-vapor- corrected imagery has the advantages of high thermal sensitivity (0.12 deg C), large synoptic coverage (nearly 3000 km across), and high spatial resolution that enables diurnal heating events to be readily located and mapped. Several case studies in the subtropical North Atlantic readily show that DOSL results during extreme heating periods agree very well with satellite-imagery-derived values in terms of the pattern of diurnal warming. The low wind and cloud-free conditions necessary for these events to occur lend themselves well to observation via infrared imagery. Thus, the normally cloud-limited aspects of satellite imagery do not come into play for these particular environmental conditions. The fact that the DOSL model does well in extreme events is beneficial from the standpoint that these cases can be associated with the destruction of the surface acoustic duct. This so-called 'afternoon effect' happens as the afternoon warming of the mixed layer disrupts the sound channel and the propagation of acoustic energy. Original contains color plates: All DTIC reproductions will be in black and white.