THE EUROPEAN METOP-A PLATFORM WAS LAUNCHED IN OCTOBER 2006 CARRYING THE INFRARED ATMOSPHERIC SOUNDING INTERFEROMETER (IASI). IN ADDITION TO THE OPERATIONAL METEOROLOGICAL PRODUCTS IASI MAKES DAILY GLOBAL MEASUREMENTS OF THE SPECTRAL SIGNATURES OF A NUMBER OF KEY TRACE GAS SPECIES OF INTEREST FOR TROPOSPHERIC ATMOSPHERIC COMPOSITION AND AIR QUALITY SCIENCE. THE METOP-A PLATFORM CARRIES THE FIRST OF THREE EXISTING INSTRUMENT COPIES THAT WILL BE LAUNCHED ON FOLLOW-UP MISSIONS TO ENSURE DATA CONTINUITY THROUGH 2020. THE NEXT PLATFORM METOP-B WILL BE LAUNCHED IN 2012 TO ALLOW A PERIOD OF OVERLAP WITH THE FIRST PLATFORM AND PROVIDE A CONTINUOUS DATASET. THIS COMES AT A TIME WHEN OUR CURRENT U.S. EOS MISSIONS ARE MATURING NPOESS WILL LIKELY HAVE VERY LIMITED CAPABILITY TO STUDY ATMOSPHERIC COMPOSITION AND THE NEXT GENERATION NASA MISSIONS HAVE YET TO BE FULLY DEFINED.THIS PROPOSAL WOULD DEVELOP A DEMONSTRATION CAPABILITY USING IASI DATA FOR CONTINUING THE LONG-TERM TROPOSPHERIC OZONE AND OZONE-PRECURSOR RECORDS FROM THE EOS MOPITT AND TES INSTRUMENTS. THIS EFFORT WOULD HELP ESTABLISH A CORE U.S. IASI SCIENCE TEAM WITH EXPERTISE TO DEVELOP DATA RECORDS FROM IASI CONSISTENT WITH THE OPTIMAL ESTIMATION APPROACH USED FOR TES AND MOPITT PROCESSING. IN COLLABORATION WITH OUR EUROPEAN PARTNERS WE WILL WORK TO ENHANCE THE LEVEL-2 PROCESSING ALGORITHMS AND PRODUCE VALIDATED IASI TRACE GAS PROFILE PRODUCTS FOR THE WIDER RESEARCH COMMUNITY. THIS WILL PREPARE THE WAY FOR THE GENERATION OF LONG-TERM DATA RECORDS THAT WILL SUPPORT SCIENCE AND MODELING ACTIVITIES IN ATMOSPHERIC COMPOSITION AND AIR QUALITY AND COMPLEMENT OTHER GROUND BASED AIRCRAFT AND SATELLITE MEASUREMENT PROGRAMS.THE P.I. FOR THIS PROPOSAL IS A MEMBER OF THE CNES IASI SOUNDING SCIENCE WORKING GROUP (ISSWG-2) AND THIS EFFORT WOULD BUILD ON EXISTING STRONG COLLABORATIONS WITH THE IASI TEAM HEADED BY DRS. THAT IS LEADING THE DEVELOPMENT OF A RESEARCH RETRIEVAL CAPABILITY ON THE EUROPEAN SIDE.