Nasa, Navy, And AES/York sea Ice Concentration Comparison of Ssm/i Algorithms with Sar Derived Values

Abstract

Previous research s t u d i e s have focused on producing a l g o r i t h m s f o r e x t r a c t i n g geophysical i n f o r m a t i o n from passive microwave d a t a regarding i c e f l o e size, sea i c e concentration, open water lead l o c a t i o n s , and sea i c e extent. These s t u d i e s have r e s u l t e d i n f o u r separate algorithms f o r e x t r a c t i n g these geophysical parameters. Sea i c e concentration estimates generated from each o f these a l g o r i t h m s (i.e., NASA/Team, NASA/Comiso, AES/York, and Navy) a r e compared t o i c e concentration estimates produced from c o i n c i d e n t high r e s o l u t i o n S y n t h e t i c Aperture Radar (SAR) Concentration, Sea I c e A l g o r i t h m Comparison 1.0 INTRODUCTION The p o l a r research community has been i n t e r e s t e d i n t h e determination o f sea i c e products from t h e a r c t i c r e g i o n since t h e launch o f the Nimbus 5 E l e c t r i c a l l y Scanning Microwave Radiometer (ESMR) i n 1972, and continued through 1987 w i t h t h e Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR). Presently, t h e p o l a r research community has focused i t s a t t e n t i o n towards the SSM/I which was launched i n June o f 1987 aboard t h e Defense Meteorological S a t e l l i t e Program (DMSP) Spacecraft F8. The SSM/I i s the f i r s t o f seven planned SSM/Is scheduled f o r launch over t h e n e x t two decades which w i l l make a v a i l a b l e passive microwave imagery o f t h e a r c t i c r e g i o n w e l l i n t o t h e twenty f i r s t century 113. Since 1972 the p o l a r research community has been developing sea i c e product algorithms designed t o e x t r a c t geophysical i n f o r m a t i o n about the a r c t i c . The focus o f these algorithms has been the generation o f i c e f l o e s i z e d i s t r i b u t i o n s , open water l e a d l o c a t i o n s , sea i c e concentration maps, and sea i c e e x t e n t (the l o c a t i o n of t h e boundary between open water and the i c e pack) which may a s s i s t i n t h e g e n e r a t i o n o f global c l i m a t e models h e l p i n g us t o f u r t h e r understand our biosphere. During t h i s p e r i o d several research teams have developed algorithms James Hol 1 i nger Space Sensing Branch Naval Research Laboratory Washington, D. C. 20375-5000 USA which produce b o t h t h e t o t a l and f r a c t i o n a l sea i c e percentages from passive microwave data. V e r i f i c a t i o n o f t h e r e s u l t s generated f r o m these sea i c e c o n c e n t r a t i o n algorithms was performed s e p a r a t e l y by v a r i o u s research teams. T h e i r approach (when ground t r u t h data was n o t a v a i l a b l e ) has been t o compare t h e r e s u l t s produced from c o i n c i d e n t d a t a sets c o l l e c t e d by m u l t i p l e sensors, then t r y and e x p l a i n any discrepancies found. High r e s o l u t i o n a i r c r a f t SAR systems can p r o v i d e such a v e r i f i c a t i o n since t h e generation o f r ...