Where the Wind Blows: The World's Winds Month by Month, Its Windiest Places, and Whether Wind Farms Stand in Them

I map mean wind speed over the world's land month by month from WorldClim 2.1 (10 m above the ground, 1970 to 2000, 5 arc minutes) and set it beside the near-surface circulation of the NCEP/NCAR Reanalysis 1 (long-term means for 1991 to 2020, 2.5 degrees). Over the oceans the trade winds average 6.7 m/s in the north and 7.0 m/s in the south and are the steadiest winds on Earth; the Roaring Forties (40 to 50 degrees south) average 10.2 m/s against 8.8 m/s at the same northern latitudes; and the monsoon reverses the wind over 12% of the area between 60 degrees north and south. Over land outside Antarctica the mean wind is 2.9 m/s; the windiest places are ice caps and ocean islands, led by Vatnajökull in Iceland (15.8 m/s). On northern land the windiest month is April, not midwinter. Setting the 5,344 wind farms of the WRI Global Power Plant Database (a 2021 snapshot) against the wind at their sites, 82% of onshore capacity stands on ground windier than its country's median, and in 17 of 21 countries with substantial listed capacity the farms are windier than the national land average. The UK averages 4.9 m/s over land, 1.7 times the world's land average. Interactive version: https://maps.tristanhotham.com/wind-map/. Data and code: https://github.com/Tristan-Hotham/wind-map. Blog post: https://blog.tristanhotham.com/2026/10/31/wind-map/. Text, figures, code (MIT) and derived data: CC BY 4.0, except that values derived from WorldClim 2.1 (Fick and Hijmans 2017) are shared for research and non-commercial use under the WorldClim terms; the WorldClim grids themselves are not redistributed (the interactive map shows them as pictures in colour classes, with values from a 0.5 degree summary). NCEP/NCAR Reanalysis 1: NOAA PSL, public domain. Wind farms: WRI Global Power Plant Database v1.3 (CC BY 4.0). Boundaries: Natural Earth (public domain) and ONS (Open Government Licence v3).