This study examines particulate matter (PM10) and sulphur dioxide (SO2) concentrations in Turkiye, one of the world's 20 largest economies with a population of more than 86 million people. The analysis covers from 2015 to 2019, a period during which pollutant levels frequently exceeded international air quality standards. While anthropogenic emissions are significant contributors, atmospheric variables also play a crucial role in pollutant dispersion and dilution. The research investigates how temperature, relative humidity, wind speed, precipitation, and boundary layer height affect pollutant concentrations in this country. Using a generalised additive model (GAM) and conducting a sensitivity analysis, the study explores seasonal and regional variations in the influence of these atmospheric variables across Turkiye, offering a national, multivariable perspective. The analysis relies on hourly data to capture diurnal variations during summer and winter. Additionally, it provides projections of pollutant concentrations for 2030 and 2050 under two IPCC climate scenarios: one assuming strong mitigation measures (RCP 4.5) and the other representing high-emission conditions (RCP 8.5). The GAM outputs show that temperature, humidity, wind speed, and precipitation affect PM10 and SO2 differently across the country, with marked regional and seasonal variations. Winter PM10 commonly peaks near similar to 10 degrees C, whereas in several regions summer concentrations decline once temperatures exceed similar to 30 degrees C; relative humidity is generally positively associated with PM10 yet negatively with SO2; stronger winds and precipitation coincide with lower pollutant levels (with PM10 highest at low winds <5 m/s and notably reduced on days with similar to 25 mm rainfall). Coastal regions show the strongest wind- and rain-related reductions in concentrations; interior continental and semi-arid regions display a weaker precipitation signal with a tighter humidity-PM10 association; and high-elevation basins and valleys are characterised by heightened sensitivity to boundary-layer stability. Sensitivity analysis indicates that boundary-layer height and wind are the primary atmospheric drivers for PM10, whereas SO2 shows a weaker overall sensitivity to atmospheric factors. Projections about the influence of atmospheric variables on pollution for 2030 and 2050 suggest that PM10 levels will generally decline across both seasons, while SO2 concentrations are expected to rise during summer. The study highlights the increasing influence of climate change on air pollution, stressing the importance of region-specific air quality management strategies. By integrating mitigation and adaptation measures, the findings offer valuable insights for policymakers aiming to improve air quality and reduce health risks across Turkiye.