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This page explains the computed climate rows on appellation and growing area pages: how the figures are worked out, which datasets they come from, and under what licences.
The Climate section of an appellation or growing area infobox shows three computed rows. They are worked out the same way for every place from open global datasets, at the place's border or point, and not from the article's own sources. A line under them names the datasets used for that place.
What the rows show
| Row | What it shows |
|---|---|
| Köppen class (computed) | The Köppen–Geiger climate class covering the largest share of the place's area, with the class name, from the 1 km map of Beck and colleagues for 1991–2020.[1] |
| Elevation (computed) | The median elevation over the place's area, with the 10th to 90th percentile range in brackets: the range within which the middle 80 per cent of the area lies. A place mapped by a point alone has one figure. |
| Closest climate matches | The five other appellations and growing areas whose climates are closest to this one, each with a similarity figure out of 100. |
An elevation written in the article from cited sources appears in its own row, under Landscape. It can differ from the computed figure, which describes the whole area.
How places are compared
Each place is described by six values:
| Value | Source | Weight |
|---|---|---|
| Maximum temperature of the warmest month (°C) | CHELSA | 1 |
| Minimum temperature of the coldest month (°C) | CHELSA | 1 |
| Annual precipitation (mm), on a logarithmic scale | CHELSA | 1 |
| Share of the year's precipitation that falls in the warmest quarter | CHELSA | 1 |
| Length of the longest day of the year (hours), from latitude[2] | Latitude | 1 |
| Median elevation (m) | GMTED2010 or Copernicus GLO-90 | 0.5 |
Precipitation is compared on a logarithmic scale because a difference of 500 mm matters far more between 500 and 1,000 mm than between 3,500 and 4,000 mm. Elevation carries half weight because the two temperatures already carry most of its effect. The Köppen class is shown but not used in the comparison, since it is itself worked out from the same monthly temperatures and rainfall.
Each value is turned into a standard score by dividing it by its standard deviation across all the wiki's appellations and growing areas. The distance D between two places is the weighted Euclidean distance between their scores, divided by the sum of the weights, and the similarity is 100 × e−D, rounded. Identical climates give 100, a distance of half a standard deviation gives 61 and a distance of one standard deviation gives 37. This is the dissimilarity measure of the CCAFS climate analogue tool.[3]
| Value | Standard deviation across the 377 places |
|---|---|
| Maximum temperature of the warmest month | 6.59 °C |
| Minimum temperature of the coldest month | 12.80 °C |
| Annual precipitation (natural logarithm) | 0.81 |
| Warmest-quarter share of precipitation | 0.18 |
| Longest day | 0.92 h |
| Median elevation | 1,091 m |
A place's own list leaves out every place whose border overlaps it, such as a growing area and the appellations inside it, and for a place mapped by a point alone, any area that contains the point. Equal distances are ordered by name.
The figures were computed for all 377 appellations and growing areas on 9 November 2026, and the standard deviations come from that same set. They change only when every place is computed again, so editing one page does not move another page's figures. A page added after that date shows no computed rows until the next run.
Sampling and resolution
- Borders. 364 of the 377 places have a mapped border; the other 13 are mapped by a point alone.
- Climate. The climate values are means over the 30 arc-second cells (about 1 km) whose centres fall inside the border. A large place is sampled on a regular grid of between 25 and 100 cells; a small place uses every cell inside it; a place with no cell centre inside its border uses the cell nearest its centre, and a place mapped by a point uses the cell that holds the point.
- Köppen class. The class of the largest number of sampled 1 km cells.
- Elevation. Copernicus GLO-90, at 90 m, for points and for places under 100 km²; GMTED2010, at about 1 km, for larger places. Each place's line names the one used.
- Day length. From the latitude of the place's centre.
Datasets and licences
| Dataset | Used for | Period and resolution | Licence |
|---|---|---|---|
| CHELSA V2.1[4][5] | Temperatures and precipitation | 1981–2010, 30 arc-seconds (about 1 km) | CC0 1.0 |
| Köppen–Geiger maps, version 3, of Beck and colleagues[1] | Köppen class | 1991–2020, 1 km | CC BY 4.0 |
| GMTED2010[6] | Elevation of places of 100 km² and over | 30 arc-seconds (about 1 km), mean elevation | U.S. public domain; the copy used is distributed with CHELSA under CC0 |
| Copernicus DEM GLO-90[7] | Elevation of points and places under 100 km² | 90 m | Copernicus DEM licence (free and open) |
The elevations from Copernicus GLO-90 are produced using Copernicus WorldDEM™-90 © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014-2018 provided under COPERNICUS by the European Union and ESA; all rights reserved. The organisations in charge of the Copernicus programme by law or by delegation do not incur any liability for any use of the Copernicus WorldDEM™-90.
See also
- Help:Geographic pages
- Module:Climate profile, which holds the figures
References
- ↑ 1.0 1.1 Beck, Hylke E.; McVicar, Tim R.; Vergopolan, Noemi; Berg, Alexis; Lutsko, Nicholas J.; Dufour, Ambroise; Zeng, Zhenzhong; Jiang, Xin; van Dijk, Albert I. J. M.; Miralles, Diego G. (2023). "High-resolution (1 km) Köppen-Geiger maps for 1901–2099 based on constrained CMIP6 projections". Scientific Data. 10 724. doi:10.1038/s41597-023-02549-6.
- ↑ Forsythe, William C.; Rykiel, Edward J.; Stahl, Randal S.; Wu, Hsin-i; Schoolfield, Robert M. (1995). "A model comparison for daylength as a function of latitude and day of year". Ecological Modelling. 80 (1): 87–95. doi:10.1016/0304-3800(94)00034-F.
- ↑ Ramírez-Villegas, Julián; Lau, Charlotte; Köhler, Ann-Kristin; Signer, Johannes; Jarvis, Andy; Arnell, Nigel; Osborne, Tom; Hooker, Josh (2011). Climate analogues: finding tomorrow's agriculture today (Report). CCAFS Working Paper. Cali, Colombia: CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). hdl:10568/16420.
- ↑ Karger, Dirk Nikolaus; Conrad, Olaf; Böhner, Jürgen; Kawohl, Tobias; Kreft, Holger; Soria-Auza, Rodrigo Wilber; Zimmermann, Niklaus E.; Linder, H. Peter; Kessler, Michael (2017). "Climatologies at high resolution for the earth's land surface areas". Scientific Data. 4 170122. doi:10.1038/sdata.2017.122.
- ↑ Karger, Dirk Nikolaus; Conrad, Olaf; Böhner, Jürgen; Kawohl, Tobias; Kreft, Holger; Soria-Auza, Rodrigo Wilber; Zimmermann, Niklaus E.; Linder, H. Peter; Kessler, Michael (2021). "CHELSA V2.1 (current)". EnviDat. doi:10.16904/envidat.228.v2.1.
- ↑ Danielson, Jeffrey J.; Gesch, Dean B. (2011). Global multi-resolution terrain elevation data 2010 (GMTED2010) (Report). Open-File Report. U.S. Geological Survey. doi:10.3133/ofr20111073.
- ↑ European Space Agency; Airbus (2022). "Copernicus DEM". European Space Agency. doi:10.5270/ESA-c5d3d65.