AMBIENT EXPOSURE TO PM2.5 IS ONE OF THE TOP GLOBAL HEALTH CONCERNS. REMOTE SENSING AND GLOBAL MODELING ARE KEY TOOLS FOR ASSESSING HEALTH IMPACTS FROM AMBIENT EXPOSURE TO PM2.5 AND FOR QUANTIFYING THE BENEFITS OF AIR POLLUTION CONTROL STRATEGIES AS THE DISTRIBUTIONS AND SOURCES OF PM2.5 CAN NOT BE SUFFICIENTLY QUANTIFIED BY IN SITU MEASUREMENTS ALONE IN MANY PARTS OF THE WORLD ESPECIALLYDEVELOPING REGIONS WHERE AIR QUALITY IS A BURGEONING ISSUE.OBJECTIVES: THIS PROJECT WILL EXPAND UPON PREVIOUS WORK PROVIDING REMOTE-SENSING AND MODEL-BASED ESTIMATES OF EXPOSURE AND HEALTHIMPACT RESPONSE COEFFICIENTS TO THE CLIMATE AND CLEAN AIR COALITION (CCAC) OF THE UNITED NATIONS ENVIRONMENT PROGRAMME. THIS WORK STEMS FROM A CCAC INITIATIVE TO DEVELOP AND APPLY NATIONAL ACTION PLANNING TOOLKITS WHICH ALLOWS MEMBER NATIONS TO RAPIDLYESTIMATE AIR QUALITY AND CLIMATE IMPACTS OF ARRAYS OF MITIGATION OPTIONS AS PART OF THEIR DECISION-MAKING PROCESS. THROUGH AQAST NASA DATA ARE CURRENTLY USED WITHIN THE INITIAL VERSION OF ONE SUCH TOOL -- THE LEAP-IBC TOOLKIT. FOR OUR CORE PROJECT WE WILL CONTINUE TO STRENGTHEN THE APPLICABILITY AND SCOPE OF LEAP-IBC THROUGH UPDATES TO THE REMOTE SENSING OBSERVATIONS AND MODELING FRAMEWORK USED IN THE TOOLKIT. WE WILL IMPLEMENT NEW MULTI-SATELLITE FUSION CONSTRAINTS ON SURFACE-LEVEL PM2.5 FROM CALIPSO MISR MODIS AND SEAWIFS DIRECTLY INTO LEAP-IBC FOR IMPROVED ACCURACY AND KM-SCALE EVALUATION OF AIR POLLUTION EXPOSURE. THE ADJOINT OF A NASA GLOBAL ATMOSPHERIC CHEMICAL MODEL (GEOS-CHEM) IS USED TO ESTIMATE THE RESPONSE OFPOPULATION-WEIGHTED PM2.5 CONCENTRATIONS TO EMISSIONS FROM ANY SPECIES SECTOR OR LOCATION AND WILL BE EXTENDED TO SERVE ALL CCAC MEMBER NATIONS AND TO PROVIDE HIGH-RESOLUTION PRODUCTS FOR CITIES INCLUDED IN THE CCAC URBAN HEALTH INITIATIVE. DELIVERY OF THESE RESULTS DIRECTLY INTO LEAP-IBC WILL HELP SERVE AIR QUALITY MANAGEMENT ACTIVITIES ACROSS A BROAD SET OF COUNTRIES AND REGIONS ENGAGED INCCAC ACTIVITIES. QUALIFICATIONS: TO SUCCESSFULLY ACCOMPLISH OUR CORE OBJECTIVES WE WILL DRAW FROM CONSIDERABLE EXPERTISE IN SCIENTIFIC AND TECHNICAL USE OF REMOTE SENSING DATA AND AIR QUALITY MODELING (HENZE) DOMESTIC AND INTERNATIONAL AIR QUALITY MANAGEMENT (ANENBERG) ANDENVIRONMENTAL HEALTH (KINNEY). FROM EXPERIENCE ON BOTH THE RESEARCH AND AIR QUALITY MANAGEMENT SIDES OF MULTIPLE AQAST PROJECTS WE ARE ALSO ABLE TO IDENTIFY LEAD AND CONTRIBUTE TO TIGER TEAM ACTIVITIES WITH CLEARLY SCOPED DELIVERABLES AND OUTCOMES ACROSS A BROAD RANGE OF TOPICS OTHER THAN THOSE HIGHLIGHTED IN OUR CORE PROPOSAL SUCH AS AIR QUALITY TOXICS URBAN HEAT ISLANDS AND EPIDEMIOLOGY.IMPACT: THIS PROJECT IS HIGHLY RESPONSIVE TO THE H-AQAST SOLICITATION AS WE PROPOSE TO USE BOTH MULTI-SENSOR SATELLITE PRODUCTS AND NASA EARTH SYSTEM MODELING TO CONTRIBUTE TO ACTIVE AIR QUALITY MANAGEMENT PROGRAMS. THIS DIRECTLY ADDRESSES TECHNICAL ASPECTS OF NATIONAL AND INTERNATIONAL ENVIRONMENTAL HEALTH AND AIR QUALITY POLICY; AIR QUALITY MANAGEMENT APPROACHES IN NUMEROUS COUNTRIES;EVOLVING POLICY NEEDS ARISING FROM INTERACTIONS AMONG AIR POLLUTION HEALTH AND CLIMATE CHANGE; AND THE NATIONAL AND INTERNATIONAL ORGANIZATIONS THAT ADDRESS THESE ISSUES. QUANTIFIABLE SOCIETAL IMPACTS INCLUDE AN EXPANDED BASE OF NATIONAL AIR QUALITY MANAGEMENT ORGANIZATIONS USING THESE TOOLS THE IMPROVEMENTS THESE TOOLS MAKE TO THEIR ABILITIES TO ESTIMATE AIR POLLUTION EXPOSURE AND ENHANCEDCAPABILITIES FOR ESTIMATING HOW THIS EXPOSURE RESPONDS TO DOMESTIC AND INTERNATIONAL MITIGATION EFFORTS. THIS WORK BUILDS DIRECTLY FROM AQAST FUNDED ACTIVITIES THAT LAID THE GROUNDWORK FOR THESE PROJECTS MATCHED BY SUPPORT PROVIDED BY THE CCAC. THE RESULTS WILL FACILITATE BROADER ADOPTION OF SATELLITE-BASED PM2.5 EXPOSURE ESTIMATES WITHIN ORGANIZATIONS SUCH AS THE UN US STATE DEPARTMENT WORLD BANK AND WORLD HEALTH ORGANIZATION AND EXPAND A SUSTAINED USER-BASE AMONG THESE ORGANIZATIONS FOR NASA PRODUCTS AND HAQAST