Altimeter and Oceanographic in Situ Measurements in the Area of the Greenland-Iceland-Norwegian Sea, 1987-1988

• Main Author: Pistek, Pavel
• Other Authors: NAVAL OCEANOGRAPHIC AND ATMOSPHERIC RESEARCH LAB STENNIS SPACE CENTER MS
• Format: Text
• Language: English
• Published: 1992
• Subjects: Physical and Dynamic Oceanography; Infrared Detection and Detectors; *OCEANOGRAPHIC DATA; *INFRARED IMAGES; *RECONNAISSANCE SATELLITES; DATA BASES; MEASUREMENT; TEMPERATURE; SHIPS; DETECTION; AIRCRAFT; MODELS; MONITORING; BATHYTHERMOGRAPHS; EXPENDABLE; NORWEGIAN SEA; NORTH ATLANTIC OCEAN; AMPLITUDE; OCEANS; CROSS SECTIONS; SIGNALS; THERMISTORS; TRACKS; ICELAND; GEOIDS; GREENLAND; ANALOGIES; HEIGHT FINDING; OCEANOGRAPHY; CONDUCTIVITY; DYNAMICS; COMPARISON; AIRBORNE; DEPTH; REGIONS; VARIATIONS; AERIAL SURVEYS; SATELLITE ALTIVETRY; Greenland; Norwegian Sea; Iceland; North Atlantic
• Online Access: http://www.dtic.mil/docs/citations/ADA256598; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA256598

A multidisciplinary oceanographic study was performed in the area of the Greenland-Iceland-Norwegian Sea (GIN Sea). To assess the usefulness and the potential of altimetry in this region, the GEOSAT data, the satellite infrared images, and simultaneous in situ measurements of (a) airborne expendable bathythermographs deployed from P-3 aircraft, and (b) ship measurements of conductivity-temperature-depth (CTD) and thermistor chain data along the altimeter tracks were collected. In addition, the historical CTD data base, Generalized Digital Environmental Model (GDEM), was studied and used with altimetry. It was found that the variation in the signal amplitude of altimetric residuals corresponding to mesoscale variability is between 5 and 15 cm. In spite of this small amplitude, the signal is correlated with the oceanographic structure. Dynamic heights computed from CTD cross sections taken along the altimeter ground tracks were used to improve the empirical geoid. The altimetric signal results, namely, across the Norwegian current and the Faeroe-Shetland inflow, indicate the possibility of monitoring the Inflow by altimeter. In analogy to the CTD method discussed, dynamic height was computed from GDEM data and was used for correcting the altimeter data. This method can be useful in some areas as a first approximation in the improvement of the geoid. In spite of the detection by altimeter of the stronger and larger mesoscale features south of the Iceland-Faeroe front, the front itself was not easily detected because of tidal contamination. Statistical results (namely variance) derived from altimetry indicate the larger variability to be near the frontal regions. Oceanography, Digital image analysis, Satellite altimeter, Satellites, Remote sensing.