Biodiversity plays a critical role in maintaining ecosystem resilience and stability, particularly in the face of increasing climate variability. As global temperatures rise and extreme weather events become more frequent, ecosystems are subjected to unprecedented stress, threatening both ecological integrity and human well-being. Diverse biological communities enhance the ability of ecosystems to buffer against environmental fluctuations by promoting functional redundancy, nutrient cycling, and adaptive responses to stressors. Evidence from forests, grasslands, wetlands, and marine systems indicates that higher species richness correlates with greater resistance to droughts, floods, and temperature extremes, thereby stabilizing ecosystem services such as carbon sequestration, water regulation, and soil fertility. Understanding the mechanisms by which biodiversity mitigates climate impacts is essential for conservation strategies, sustainable resource management, and policy frameworks aimed at enhancing global ecological resilience.