{"version_information": {"version": "det_AHW_v1.1", "compiled_date": "2026-04-05 17:09:20.619530", "data_source": "ERA5", "website": "http://wexa.jamstec.go.jp", "Author": "Patrick Martineau"}, "event_id": {"name": "Event ID", "description": "A unique identifier based on: beginning_date, end_date, longitude, and latitude", "value": "2025-Dec-17_to_2025-Dec-21_273.0_55.5"}, "event_label": {"name": "Event label", "description": "Integer-valued grid identifier that uniquely labels each detected extreme event in space and time, consistent with the corresponding labels stored in the NetCDF dataset.", "value": 2025120000615}, "status": {"name": "Status", "description": "An ongoing event denotes an event that lasts up to the latest data available. These events are subject to change as newer data is added.", "value": false}, "start_date": {"name": "Start date", "description": "First date on which grid points are under the influence of an event", "value": "December 17 2025"}, "end_date": {"name": "End date", "description": "Last date on which grid points are under the influence of an event", "value": "December 21 2025"}, "duration": {"name": "Duration", "description": "Time elapsed (days) from the start date to the end date", "value": 5}, "figures_available": {"name": "Figures available", "description": "True if figures were pre-generated for this event", "value": true}, "detection_var": {"name": "Detection variable", "description": "Variable used for the detection scheme", "value": "t2m"}, "event_type": {"name": "Event type", "description": "Type of the event detected", "value": "Cold spell"}, "area": {"name": "Area", "description": "The area (in square meters) encompassing all grid points under the influence of an event during its lifetime.", "value": 112783.23827978138}, "countries_affected": {"name": "Countries affected", "description": "The ArcGIS geocoding API (https://developers.arcgis.com/rest/geocode/) is used to obtain a list of all the countries affected by an event during its lifetime.", "value": ["Canada"]}, "continents_affected": {"name": "Continents affected", "description": "List of all continents affected", "value": ["America"]}, "oceans_affected": {"name": "Ocean basins affected", "description": "The ArcGIS geocoding API (https://developers.arcgis.com/rest/geocode/) is used to obtain a list of all the ocean basins affected by an event during its lifetime.", "value": []}, "center_lat": {"name": "Center latitude", "description": "Latitude of the maximum time-integrated standardized t2m anomalies. Only t2m of the same polarity as the events are considered (positive T2m for a HW, for instance). The centre is thus representative of both the severity and persistence of anomalies.", "value": 55.5}, "center_lon": {"name": "Center longitude", "description": "Longitude of the maximum time-integrated standardized t2m anomalies. Only t2m of the same polarity as the events are considered (positive T2m for a HW, for instance). The centre is thus representative of both the severity and persistence of anomalies.", "value": 273.0}, "center_latf": {"name": "Center latitude", "description": "Formatted version of center longitude", "value": "273.0\u00b0E"}, "western_lon": {"name": "Westernmost longitude", "description": "Westernmost longitude affected by event", "value": 264.5}, "eastern_lon": {"name": "Easternmost longitude", "description": "Easternmost longitude affected by event", "value": 275.5}, "southern_lat": {"name": "Southernmost latitude", "description": "Southernmost latitude affected by event", "value": 54.5}, "northern_lat": {"name": "Northernmost latitude", "description": "Northernmost latitude affected by event", "value": 58.5}, "polygons_merged": {"name": "Merged polygon", "description": "Merger or polygons at each time step", "value": {"type": "MultiPolygon", "coordinates": [[[[-86.0, 56.25], [-85.75, 56.15], [-85.5, 56.25], [-84.97, 56.03], [-84.82, 55.68], [-84.47, 55.53], [-84.32, 55.18], 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