缺水压力、水相关危害和水质对现代社会构成了日益严峻的挑战。然而，对这一重要资源的监管能力是分散且不足的。全球数十亿人也通过水感受到了气候变化的影响。
便于获取的饮用水对人类健康、稳定的人类社会和可持续的生态系统至关重要 – 因此，水资源短缺有可能导致政治和社会动荡。超过7.8亿人-约占世界人口的11%-无法获取清洁、安全的水。更令人担忧的是，据估计，世界上大约一半的医院病床上住着患有与水有关疾病的患者。
水资源面临着压力，日益增加的需求更是雪上加霜，同时气候变化正在加剧水圈变迁，诱发更多极端天气事件，降低供水可预测性并影响水质。反过来，这种连锁后果又威胁到了全世界的可持续发展、生物多样性以及享有饮水和卫生设施的人权。
在世界各地，数十亿人也通过水感受到了气候变化的影响。由于风暴、强风、强降水和干期等自然事件的强度增加，与水相关灾害的频率正在上升。洪水、干旱、山体滑坡、冰川湖溃决和风暴潮正在影响沿海地区和山顶、干旱平原和沙漠、河岸和洪泛平原上的生活和基础设施。最贫穷和最不发达的地方是最脆弱的。
Risk assessment, proper planning and mitigation are the cornerstones of any National Meteorological and Hydrological Service (NMHS) measure to reduce flood risks. Timely forecasts and warnings must be produced at the regional, national and local levels and be communicated through the appropriate authorities in language that they understand.
IDMP will be supported by climatological and hydrological prediction capabilities, water resources management, the Global Hydrological Status and Outlook System (HydroSOS), Regional Climate Centres (RCCs) and Global Data-processing and Forecasting System (GDPFS). Drought risk management should be undertaken by Members and through WMO regional climate centres.
WMO supports resolving the equation of water demand for human consumption, irrigation requirements, water availability and potential water storage and provides advice to optimize rainfed and irrigated agriculture. The water-energy-food nexus should be considered as well.
WMO Global Hydrological Data Centres take the lead in this area. They will benefit in this task from further developments in the Global Hydrometry Support Facility (HydroHub), especially its Innovation Hub and Quality Management Framework, the World Hydrological Cycle Observing System (WHYCOS), and the Meteorological, Climatological and Hydrological Database Management System (MCH). These are all essential for the wise management of water resources.
Operational hydrology would benefit from an improved understanding of the impacts of various stressors on the hydrological cycle, in support of closing the water balance.
Further development of WMO initiatives, such as WHOS, HydroSOS and the Global Cryosphere Watch, matched with other international efforts, should support a fully operational World Water Data Initiative and enable local and global assessments of the availability of water resources.
Hydrological information should be available at the time and space necessary to optimze operational water resources management in support of water-dependent sectors and for planning and adapting to transient environmental conditions, particularly those associated with climate change.
A new partnership is needed to support this ambition, including existing links to the Global Environment Monitoring System-Water (United Nations Environment Programme), the United Nations Educational, Scientific and Cultural Organization (UNESCO) and other relevant stakeholders.
