Global Precipitation for the Year 2023: A Summary and How the Year Fits Into the Trends Associated with Global Warming

Global precipitation totals, patterns and trends for 2023 are summarized using analyses from the Global Precipitation Climatology Project (GPCP) Monthly analyses, including NOAA’s Interim Climate Data Record (ICDR) GPCP product for the last few months of the year.

In 2022 the global precipitation pattern and the associated anomaly map for the year was dominated in the tropics and beyond by the strong presence of La Nina during the entire year. The mean Nino 3.4 SST Index was -0.9 for 2022. For 2023 the early months of the year the Index was still negative, but by April it had transitioned to positive and by July the Index was +1.0, indicating a moderate El Nino. The tropical Pacific Ocean ENSO rainfall anomaly pattern also transitioned during the first half of the year, looking more like a typical El Nino pattern with positive anomalies in the central/eastern Pacific, although beyond that region the mid-year anomaly pattern was not typical of an on-going El Nino. Results will be presented as to the ENSO variations for the rest of 2023 and the final result for the year as a whole.

The year 2023 will also likely be one of the hottest years on record globally and how that relates to the global precipitation totals and distributions will be examined. Although total global precipitation increases at a slow rate with global temperature increases, the estimated global precipitation totals in the first half of the year are near records. The pattern of global precipitation trends over the last 40 years will also be examined, including 2023, and the anomaly pattern for 2023 will be examined to determine if it reinforces the long-term trend pattern.

Other large-scale trends (and where 2023 fits in) will also be examined, including the trends in the ITCZ belt (0-10°N) and the Sub-tropical belt (30-40°N), which show clear trends of the “wet-getting-wetter”, “dry-getting-drier” variety.