The Caribbean region is one of the most affected by climate changes and extreme hydrometeorological phenomena, such as hurricanes, storms, floods, droughts, and heat waves. Many Caribbean countries are currently experiencing complex water security challenges, including water scarcity, pollution, watershed degradation, saline intrusion, and flooding. All these factors have a negative impact on the water security of the Caribbean States. This seminar, co-organized by the Intergovernmental Hydrological Program for Latin America and the Caribbean (IHP-LAC) and the World Meteorological Organization (WMO), seeks to present some of the hydrological challenges that Caribbean States face in terms of Climate Change and the actions that are being carried out to strengthen water security.

Climate change has shown that its effects are real and still incalculable. Processes typical of the usual climatic variability in nature (phenomena such as El Niño and La Niña), which together with other processes generate drought events, torrential rains, heat waves, etc., behave in a more aggressive and anomalous way due to the increase in temperatures and the increase in greenhouse gases. This process is proving devastating for the economies of many countries in Latin America and the Caribbean, for many natural ecosystems and for human settlements. One of the ways for nations to cope with these phenomena is adaptation: modifying some of the usual patterns of productive and technological behaviour, public or social policies.  

The Uruguay River is an important water resource within the Plata Basin, which receives contributions from a 370,000 km² water basin, whose aquatic systems provide services for the provision of water and drainage evacuation, as well as for recreation and tourism activities, agricultural and industrial production and navigation, as the most relevant. These services are affected by the increasing presence of potentially toxic cyanobacterial blooms that put health and production at risk. It is known that the development of these organisms is strongly favored by the entry of nutrients into the system, such as phosphorus and nitrogen, and by other factors of greater or lesser incidence depending on the context. Preventing the advance of these events or their development in new places, would be the best control strategy; but also the most difficult. Anticipating their appearance or knowing their movements would be a feasible strategy to avoid some negative effects of cyanobacterial blooms. But when the event is already in place, mitigation measures allow damage to be reduced.