The rapid development and expansion of High-Performance Computing (HPC) systems present signif- icant environmental challenges, primarily due to substantial energy consumption and associated carbon emissions, often from non-renewable sources. This paper provides a comprehensive analysis of the en- vironmental footprint of HPC. It models global energy consumption, considering both full capacity and average utilization rates (estimated at 12-18%). A model is developed to quantify total carbon emis- sions, accounting for diverse energy sources, regional energy mixes, and conversion efficiencies. The analysis explores future trends by considering projected HPC growth, increasing energy demand from other sectors, and potential shifts in energy sources, forecasting impacts up to 2030 using time series analysis. The study further investigates the potential for mitigation by modeling the relationship be- tween increased renewable energy adoption and carbon emission reductions, including a scenario for 100% renewables. Additionally, the model is expanded to include water usage, another critical environmental factor, analyzing its relationship with energy consumption. Based on these models, actionable technical and policy recommendations are proposed to enhance energy efficiency and promote sustainability in the HPC sector, emphasizing the need to integrate these concerns into future development and climate change mitigation strategies.