On the Validation of Satellite-Derived Sea Ice Surface Temperature

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1993
• Subjects: Arctic; Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.529.4863; http://pubs.aina.ucalgary.ca/arctic/Arctic47-3-280.pdf

ABSTRACT. The surface temperature of sea ice controls the rate of ice growth and heat exchange between the ocean and the atmosphere. An algorithm for the satellite retrieval of ice surface temperature has recently been published, but due to the lack of validation data has not been extensively tested. In this paper, data from a recent Arctic field experiment is used in an attempt to validate that algorithm. While the procedure is, in principle, straightforward, we demonstrate that validation is complicated by a variety of factors, including incorrectly assumed atmospheric conditions, undetected clouds in the satellite data, spatial and temporal variability in the surface temperature field, and surface and satellite measurement errors. Comparisons between surface temperatures determined from upwelling broadband longwave radiation, spatial measurements of narrow-band radiation, thermocouples buried just below the snow surface, and narrow-band satellite data show differences of 1 to 3˚C. The range in these independent measurements indicates the need for specially designed validation experiments utilizing narrow-band radiometers on aircraft to obtain broad spatial coverage. Key words: ice surface temperature, Arctic climate, sea ice, AVHRR RÉSUMÉ. La température de la surface de la glace de mer contrôle le taux de croissance de la glace et les échanges thermiques entre l’océan et l’atmosphère. Un algorithme d’extraction par satellite de la température de la surface de la glace a récemment été publié, mais n’a pu être mis à l’essai sur une grande échelle, en raison du manque de données de validation. On tente, dans cet article, de valider cet algorithme à l’aide de données provenant d’une expérience de terrain menée récemment dans l’Arctique. Si la procédure est, en principe, simple, on démontre que divers facteurs viennent compliquer cette validation, dont une évaluation incorrecte des conditions atmosphériques, la