This chapter presents a comprehensive assessment of future climate projections for the Arabian Peninsula using Coupled Model Intercomparison Project Phase 6 (CMIP6) models, under two key emission scenarios SSP2-4.5 (a stabilization scenario) and SSP5-8.5 (a high-emissions scenario), for mid-century (2041–2060) and end-century (2081–2100) timeframes. The findings reveal a region-wide and progressive warming trend across all countries of the Arabian Peninsula, with particularly severe increases projected under the high-emission SSP5-8.5 scenario. By mid-century, Iraq, Kuwait and Saudi Arabia are among the most affected, with mean temperature (Tmean) increases reaching up to + 2.5 °C and minimum temperatures (Tmin) at + 2.6 °C, underscoring the likelihood of persistent night-time heat and diminished diurnal cooling. By the end of the century under the SSP5-8.5 scenario, Iraq emerges as the hottest country, with maximum temperatures (Tmax) projected to increase by + 5.9 °C, while Kuwait, Saudi Arabia and Jordan follow closely with increases of + 5.6 °C and + 5.5 °C, respectively. Minimum temperatures (Tmin) also show substantial rises, reaching + 5.9 °C in Saudi Arabia and + 5.8 °C in Kuwait, indicating severe and persistent night-time heat stress. These extreme thermal conditions are expected to amplify public health risks, increase energy demand for cooling and place substantial strain on infrastructure and natural ecosystems. In addition, precipitation projections reveal a more complex spatial pattern. Yemen is projected to experience the highest increase in annual precipitation across the region, particularly under the SSP5-8.5 scenario, with a rise of up to + 66.3 mm, whereas countries like Jordan and Iraq face persistent drying trends, indicating growing water scarcity risks. These results underscore the urgent need for differentiated, region-specific adaptation strategies across the Arabian Peninsula. Countries facing extreme heat should prioritize heat-health action plans, urban cooling initiatives and thermal-resilient infrastructure. Simultaneously, water-stressed nations must implement drought preparedness, water conservation policies and transboundary cooperation. The clear divergence between the two emissions scenarios also highlights the critical importance of mitigation, as lower emissions could substantially reduce both temperature extremes and precipitation variability. This study emphasizes the strategic role of climate modeling in informing future resilience and adaptation planning in one of the world’s most climate-vulnerable regions.