Oceanic changes have a long-term effect on 2.15 billion people living near coasts and 898 million in low-elevation coastal zones. 

Coastal areas are highly susceptible to natural and climatic hazards such as erosion, saltwater intrusion, coastal aquifers, and coastal flooding due to extreme sea levels, compounded by fluvial flooding during heavy precipitation or increased snow melt. To address this, coastal communities are elevating buildings or constructing seawalls, dykes and levees to shield people and property from flooding and surge. Others are focusing on land use planning, restoring coastal ecosystems with nature-based tactics to restore ecosystem resilience. In order to reduce risks, it is likely that developed and densely populated urban areas will rely on hard protection measures. However, maintaining safe human settlements in remote and rural areas will be challenging, since they are the ones most affected by climate change and its impacts on local resources and livelihoods.

Nearly 80% of the world’s wastewater is still discharged into the sea without treatment. When concentrated in small, confined, and overcrowded areas such as coastal zones - sewage, chemicals and heavy metals from both domestic and industrial runoffs pose a serious threat to life in the sea and human health through sectors like fishing and seafood. It is becoming increasingly important to develop policies toward better infrastructure in developing nations for wastewater treatment and interceptions, and to limit over consumption and pollution from developed nations.