Reinforced concrete (RC) coastal structures are experiencing an increased risk of early deterioration, influenced by various factors accelerated by climate change. Evaluating their condition is essential for enhancing strength and extending their service life. This study investigates the impact of changes in atmospheric parameters (relative humidity (RH), temperature, and carbon dioxide (CO2)), structural parameters (clear cover, water-cement ratio (w/c)), and exposure conditions, employing deterioration models. The long-term effect of deterioration agents is investigated by projecting into the far future for RCP scenarios 4.5 and 8.5. Although the changes in the atmosphere are slow to visualize over the lifespan of the structure, the effect of the changes directly affects the deterioration processes, making it early and rapid. Particularly, the increase in temperature and salinity initiates the deterioration process earlier than it would in the ideal scenario for which the coastal structures are designed. The study is conducted integrating deterioration models and climate change scenarios of temperature and CO2. Results indicate that the time for corrosion initiation decreases with rising temperature, RH, and w/c. Probabilistic analysis conducted using the Monte Carlo simulation method reveals that 92% to 99% of structures under various exposure conditions experience early deterioration compared to a scenario without climate change. Furthermore, the study employs a nomograph approach to provide projection charts of deterioration mechanisms, accounting for the climate change impact on structural and atmospheric parameters.