Global water monitor 2023: Summary report

The Global Water Monitor provides free, rapid and global information on climate and water resources. This summary report contains information on rainfall, air temperature, humidity, soil and groundwater conditions, vegetation access to water, river flows, flooding, and lake volumes in 2023. Trends in the water cycle and some of the most important hydrological events of 2023 are interpreted and discussed.

The highlights of this report, include the following:

• Precipitation was close to average. There does not appear to be a clear trend towards more monthly high or low rainfall extremes.
• Average temperature was the highest recorded globally and in 77 countries. The frequency of record-warm months was also the highest observed.
• Relative air humidity was the second lowest on record, continuing a trend towards drier average and extreme conditions. Drier-than-normal conditions prevailed nearly everywhere.
• Despite warmer and drier conditions, high annual soil water conditions were observed in many regions.
• Vegetation vigour was the highest since 2001, continuing a steady increase over the last decades.
• Surface water occurrence from water bodies and flood events was the second lowest in two decades, but months with record high water occurrence appear to be increasing globally.
• River flows were slightly lower than the previous year. Record high river flows appear to be getting more common, and record low flows less common.
• Lake volumes have been increasing over recent decades. High storage records are broken more often.
• Many dry and wet records in terrestrial water storage - combining all parts of the terrestrial water cycle - were broken in 2023, despite several missing months of missing data.