PROPOSAL SUMMARY OBJECTIVES: WE AIM TO UNDERSTAND THE ATMOSPHERIC SPECTRA STRUCTURE AND COMPOSITION OF THE ATMOSPHERES OF GIANT EXOPLANETS IN THE ERA OF THE JAMES WEBB SPACE TELESCOPE. JWST WILL PROVIDE RICH DIAGNOSTICS ON THE ATMOSPHERES OF A WIDE RANGE OF TRANSITING AND DIRECTLY IMAGED PLANETS IN PARTICULARLY IN THERMAL EMISSION FOR BOTH KINDS OF OBJECTS AND IN TRANSMISSION FOR TRANSITING PLANETS. WE EXPECT THAT FOR HYDROGEN-DOMINATED ATMOSPHERES FROM SUB-NEPTUNES TO SUPER-JUPITERS OVER THE NEXT 3 YEARS TO SEE SIGNIFICANT GAINS IN OUR KNOWLEDGE. THE FIELD WILL MOVE FROM OUR CURRENT PROVISIONAL UNDERSTANDING TO FINALLY BEING PLACED ON SECURE FOOTING WITH SIGNIFICANTLY OBSERVATIONAL AND THEORETICAL WORK. THIS PROPOSAL IS FOCUSED ON THE ESSENTIAL MODELING AND THEORETICAL WORK THAT IS NEEDED TO MAKE THESE POTENTIAL GAINS A REALITY. THIS INCLUDES MODELING TOOL UPGRADES AS WELL AS LEVERAGING OUR INVOLVEMENT IN GROUNDBREAKING JWST YEAR-1 OBSERVATIONS SUCH AS GUARANTEED TIME OBSERVATIONS (GTO) EARLY RELEASE SCIENCE (ERS) AND CYCLE 1 OBSERVATIONS. METHODOLOGY: OUR GROUP HAS LONG PIONEERED THE USE OF 1D RADIATIVE-CONVECTIVE MODELS WITHIN THE SELF-CONSISTENT FRAMEWORK. WITHIN THESE MODELS WE CAN EXPLORE THE ROLE OF CONVECTION INCLUDING MODIFICATIONS TO ADIABATIC STRUCTURE CLOUD OPACITY WITHIN THE FRAMEWORK OF A PHYSICALLY MOTIVATED CLOUD MODEL STELLAR IRRADIATION ACROSS A RANGE OF HOST STAR TYPES AND A VARIETY OF CHEMICAL ABUNDANCES. WE AIM TO SIGNIFICANTLY UPGRADE A NUMBER OF ASPECTS OF OUR MODELING TOOLS INCLUDING OUR TABULATION OF ATMOSPHERIC OPACITIES OUR TREATMENT OF NON-EQUILIBRIUM CHEMISTRY DUE TO VERTICAL MIXING AND THE RADIATIVE TRANSFER SOLVER WE USE FOR INCIDENT FLUXES. FURTHERMORE THIS WORK WILL BE PAIRED WITH INVERSE MODELS ( ATMOSPHERIC RETRIEVAL") WHERE APPROPRIATE IN TANDEM WITH SELF-CONSISTENT MODELS TO YIELD THE LARGEST GAINS IN OUR UNDERSTANDING OF THESE ATMOSPHERES. ADDITIONAL WORK WILL FOCUS ON THE USE OF MACHINE LEARNING ALGORITHMS TO UNDERSTAND WHAT JWST OBSERVATIONAL SETUPS WILL BRING THE GREATEST GAINS IN ATMOSPHERIC KNOWLEDGE. RELEVANCE: THE PROPOSED MODELING INVESTIGATIONS SEEK TO ADVANCE OUR KNOWLEDGE AND UNDERSTANDING OF THE ATMOSPHERIC COMPOSITION AND STRUCTURE OF EXOPLANETS. THE WORK IS WELL SUITED TO THE NASA EXOPLANETS RESEARCH PROGRAM WHOSE "BROAD OBJECTIVES INCLUDE THE DETERMINATION OF COMPOSITION DYNAMICS ENERGETICS CHEMICAL BEHAVIORS OF EXTRASOLAR PLANETS..."