This datasource includes a map of the 90th percentile accumulated chill hours at a 0.25 x 0.25 degree (~25km x 25km) resolution, global, for each hemisphere's "winter" months, resampled to a resolution of 10km x 10km. This map was created by performing chill hours calculations on gridded hourly temperature data from 'ERA5 hourly data on single levels from 1940 to present'. A 'chill hour' was assumed to be an hour where the temperature was between 0°C and 7.2°C. Northern hemisphere winter months were assumed as: December, January, February inclusive. Southern hemisphere winter months were assumed as: June, July, August inclusive.
A public project on the Demeter platform. Pan, zoom and inspect the dataset — no account needed.
Live values from Lazio across the annual layers published for this domain.
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Uses the same public API that powers this page. Browse the master region links below for the pages currently surfaced on the site.
Request a link for each file and use them in GIS, Python, R or AI workflows.
One downloadable layer per year.
Mean across the full covered period.
Dry-year benchmark across the covered period.
Wet-year benchmark across the covered period.
Inter-annual variability across the covered period.
Longer history, additional frequencies and regional workflows are available through Demeter.
Selected Demeter indices that reference this dataset family.
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Explore regional landing pages for the current domain and jump to other domain views.
Demeter’s winter chill data covers Global, 2015–2023. Coverage can be inspected directly in the map viewer on this page, and a wider range of data on winter chill is available in the downloads section above. Longer history and wider coverage are available through the Demeter platform.
Downloads from this page are provided as the formats shown in the downloads section on this page. Every Demeter dataset is built to be legible to AI, so the quickest way to inspect one is to open it with Claude, ChatGPT or another AI platform. Datasets with a map component also open in GIS software, including the free open-source QGIS as well as ArcGIS. Numerical and tabular data is provided in Microsoft Excel-compatible formats such as XLSX and CSV.
Click any point in the map viewer on this page and Demeter returns the values at that location. For many datasets you can also use the location search below the viewer to look up a place by name and read its values. Neither needs GIS software, a download or an account.
Demeter updates winter chill data as new source data is published. The period currently published on this page is 2015–2023. Higher-frequency series, longer history and release notifications are available through the Demeter platform.
Demeter’s datasets are compiled from a wide range of proprietary, public and third-party sources. Where a Demeter dataset incorporates third-party data without substantial additional processing, that source is prominently attributed in the dataset description.
Yes. All Demeter data is standardised onto a common taxonomy, so winter chill can be compared and combined directly with every other Demeter dataset, across regions and across domains. The same conventions apply wherever you use the data — on this page, on the Demeter platform and through the Demeter MCP server.
Downloads from this page are made available free of charge, subject to appropriate citation. The Demeter platform provides access to all Demeter data across every domain in our coverage universe, and is primarily intended for institutional, corporate and large independent users. Access to our full data coverage is available via subscription and one-time purchases. Please enquire at [email protected] for more details.
When incorporating data from Demeter into your work or materials, please attribute us as Demeter, Demeter Data or demeterdata.ag. In charts, articles and model outputs, “Source: Demeter” with a link to this page is sufficient. For a formal reference, cite: Demeter (2015–2023) Winter Chill. https://demeterdata.ag/resources/domain/winter_chill.
Yes, and Demeter datasets are built for it. Download a file and open it directly in Claude, ChatGPT or another AI platform. To connect an agent or application to Demeter data live, point it at the Demeter MCP server at https://mcp.demeterdata.ag/mcp