The continuous rise in atmospheric CO₂ concentrations due to intensified fossil fuel combustion has accelerated global climate change, highlighting the need for effective mitigation strategies. Mangrove ecosystems, recognized as vital blue carbon sinks, sequester substantial amounts of carbon in both biomass and sediments, contributing significantly to long-term carbon storage. However, large-scale degradation, land-use conversion, and declining mangrove cover have diminished their capacity to sequester carbon and increased the risk of carbon release into the atmosphere. Changes in mangrove extent directly influence aboveground and belowground carbon stocks, sediment carbon burial, and overall ecosystem stability. Conversely, conservation, restoration, and afforestation initiatives have demonstrated strong potential to enhance carbon capture while improving coastal resilience. This review synthesizes recent findings on global mangrove cover change and evaluates its implications for carbon sequestration and climate change mitigation. Strengthening mangrove conservation and sustainable management is essential to maintain their role as an effective nature-based solution for regulating atmospheric CO₂ concentrations.