**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** AGRICULTURE FACES THE LARGEST CLIMATE CHANGE EXPOSURE OF ANY ECONOMIC SECTOR. WE PROPOSE A PROGRAM OF FUNDAMENTAL ENVIRONMENTAL AND NATURAL RESOURCE RESEARCH TO ENHANCE UNDERSTANDING OF THE POTENTIAL CONSEQUENCES OF CLIMATE CHANGE FOR THE ECONOMIC HEALTH OF US FARMERS. THE PROJECT WILL INVESTIGATE HOW THESE CONSEQUENCES DEPEND ON THE INTERACTION BETWEEN TWO CHANNELS OF CLIMATE CHANGE IMPACT. THE FIRST IS THE DIRECT CHANNEL OF CHANGING LONG-RUN METEOROLOGY ON DOMESTIC CROP YIELDS. THE SECOND, INDIRECT CHANNEL ENCOMPASSES THREE DRIVING FORCES: CHANGINGMETEOROLOGY AFFECTING THE DISTRIBUTION OF SHOCKS TO THE YIELDS OF FARMERS IN OTHER WORLD REGIONS, THE EXTENT AND EFFECTIVENESS OF ACTIONS UNDERTIAKEN BY DOMESTIC AND FOREIGN FARMERS TO ADAPT TO THESE SHOCKS, AND THE CONSEQUENCES OF FOREIGN YIELD SHOCKS AND ADAPTATION FOR CHANGES IN INTERNATIONAL AGRICULTURAL COMMODITY PRICES. USING THE LATEST ECONOMETRIC TECHNIQUES AND DATA, WE WILL EMPIRICALLY ESTIMATE THE RESPONSES OF CALORIE CROP YIELDSTO LONG-RUN METEOROLOGY AND CO2 FERTILIZATION, THE POSSIBILITIES FOR PRODUCER ADAPTATION THROUGH ACREAGE ADJUSTMENTS AND IRRIGATION EXPANSION, AND THE JOINT EFFECTS OF YIELD AND COMMODITY PRICE SHOCKS ON US FARM REVENUE AND CONSOLIDATION. WE WILL COUPLE THESE RESPONSES WITH NEWLY-AVAILABLE CLIMATE MODEL OUTPUTS TO PROJECT THE IMPACTS OF, AND ADAPTATION TO, CLIMATE CHANGE CIRCA 2050. WE WILL INTEGRATE THESE SHOCKS INTO A INTERREGIONAL COMPUTABLE GENERAL EQUILIBRIUM (CGE) MODEL THAT REPRESENTS IRRIGATED AND RAINFED CROP PRODUCTION IN THE WORLD'S MAJOR RIVER BASINS, AND--INNOVATIVELY--INCORPORATES ELASTICITIES CALIBRATED TO MATCH OUR EMPIRICAL ADAPTATION RESPONSES. CGE SIMULATIONS WILL ELUCIDATE THE JOINT CONSEQUENCES OF YIELD SHOCKS, ADAPTATION POTENTIALS AND CLIMATICALLY DRIVEN HYDROLOGIC CONSTRAINTS ON IRRIGATION FOR MID-CENTURY COMMODITY AND INPUT PRICES. THESE PROJECTIONS WILL BE COUPLED WITH OUR FITTED EMPIRICAL MODEL OF US FARMS TO ASSESS IMPLICATIONS FOR DOMESTIC PRODUCER PROFITABILITY, RURAL LIVELIHOODS, AND GOVERNMENT SUPPORT PROGRAMS IN COMING DECADES.