The theme of this year's World Wetlands Day on 2 February, 'Upstream-Downstream,' highlighted how the world's wetlands are connected to livelihoods, safety and security of millions of people who depend on them for water supply and to help regulate floods. Climate change will magnify these problems, making the resilience of wetlands a fundamental issue that must be part of climate change adaptation strategies.

The Niger River Basin stretches from the highlands of Guinea to the Niger Delta.  It links ten countries and is an extremely valuable wetland and water resource in the Sahelian zone. In recent years rainfall has declined  and is expected to decline by a further 20 percent over the next 100 years.  Analysis by Wetlands International suggests that upstream dams for hydropower and irrigation will worsen the impacts of climate change. The combination of both impacts is likely to reduce river flow to the immense downstream Inner Niger Delta to the point where current downstream fishery, cattle-grazing and agricultural activities, supporting more than a million people and the provision of wintering areas for millions of water birds, will be affected severely. Alternative approaches to power generation and more effective irrigation will become even more crucial to maintain the system's resilience.

In other regions of the world it is evident how climate change is affecting entire river basin systems, such as in the Himalayas. Lakes, floodplains and high altitude peatlands regulate river water flows and ensure water supply for the region by slowly releasing stored water. Climate change alters rainfall patterns and accelerates glacial melt due to rising temperatures. With the loss of glaciers, the region looses a precious fresh water stock and a constant flow of meltwater. Reclamation of lakes, overgrazing, drainage and mining of high altitude peatlands reduces the water storage capacity of these wetlands. This can contribute to more intense floods after extreme rainfall and will worsen droughts after prolonged periods without precipitation. Wetland conservation and restoration is crucial for the 1.5 billion people living in densely-populated, downstream areas in India, China and Bangladesh. A similar story applies to the wetlands in the Andes.