2021年全球水资源状况报告

Contents Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 Introduction............................................7 Discharge 2021: Global and regional perspectives. . . . . . . . . . . . . . . . . . . . .9 Terrestrial water storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Global perspective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 High-impact events 2021. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Global perspective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Local perspectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 Cryosphere water resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 General concepts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Regional examples 2021. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 Conclusions............................................28 Annexes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30 List of acronyms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Foreword This first WMO annualState of Global Water Resourcesreport has been launched in response to calls made,for example during COP 27 in Egypt, for accurate water data and information to guide discussions. It is also an important milestone along the roadto the United Nations 2023 Water Conference. This WMO flagship report gives a concise Managers, decision makers and policymakers at all levels of government make regular useof accurate and reliable georeferenced data to guide and support their work. However, aconcise overview of water availability in the various compartments of the hydrological cycleis missing from their arsenal of decision-making support tools. While several universal The annual WMOState of Global Water Resourcesreport provides important insights for water resource management, at the basin, continental and global scale. This hassignificant relevance, particularly for large-scale decision-making and policymaking, butalso for informing and guiding intergovernmental discussions related to water resources. As a first, ‘pilot’ edition, the present WMOState of Global Water Resources 2021report is limited to the conditions of streamflow, terrestrial water storage and selected cryosphereparameters. Global Hydrological Modelling Systems and remotely sensed data were largelyused in preparing the 2021 report, and the indicators obtained from these were compared andvalidated against observational data (where available). Despite a good correlation betweenmodelled and observed results, the validation process would benefit substantially fromutilizing further hydrological information. Therefore, I would like to take the opportunityto invite Members to share hydrological information in accordance with theWMO Unified I warmly congratulate the experts, lead authors and all contributors who compiled this reportusing observed and modelled streamflow data, remotely sensed terrestrial water storagedata, other observations collected from various sources, and information on cryosphereand major hydrological disasters. Likewise, I thank all the contributors, particularly WMOMember National Hydrological and Meteorological Services, WMO Global Data Centres,members of the global hydrological modelling community (established under the Waterand Climate Coalition) and supporting organizations, National Aeronautics and SpaceAdministration (NASA) and the German Research Centre for Geosciences (GFZ). The 2021 Prof. Petteri TaalasSecretary-General, WMO Acknowledgements WMO is grateful to the following contributors: WMO Members who assignedState of Global Water Resourcesreport focal points (at thetime of writing) Armenia; Belgium; Belize; Bhutan; Brazil; Bulgaria; China; Czechia; Egypt; Ghana; Hungary;Hong Kong, China; India; Kazakhstan; Latvia; Montenegro; Myanmar; Norway; Paraguay;Peru; Philippines; Poland; Republic of Korea; Republic of Moldova; Singapore; Slovenia; SouthAfrica; Sweden; Tajikistan; Thailand; United Kingdom of Great Britain and Northern Ireland;and the United Republic of Tanzania, who contributed to and supported the preparation of WMO Members who assigned HydroSOS focal points (at the time of writing) Bangladesh; Burundi; Costa Rica; El Salvador; Guatemala; Kenya; Nepal; Panama; Rwanda;and Uganda. Steering Committee members Jan Danhelka (Czechia, Chair, Hydrological Coordination Panel); Johannes Cullmann(Sustainable Development Team Leader at the Office of the UN President of the GeneralAssembly); Narendra Tuteja (Australia); Yuri Simonov (Russian Federation, Chair of theStanding Committee on Hydrological Services); Harr