{"version_information": {"version": "det_AHW_v1.1", "compiled_date": "2026-04-05 17:07:40.731500", "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-Sep-21_to_2025-Sep-26_356.0_50.5"}, "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": 2025090000571}, "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": "September 21 2025"}, "end_date": {"name": "End date", "description": "Last date on which grid points are under the influence of an event", "value": "September 26 2025"}, "duration": {"name": "Duration", "description": "Time elapsed (days) from the start date to the end date", "value": 6}, "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": 132460.03924763744}, "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": ["United Kingdom"]}, "continents_affected": {"name": "Continents affected", "description": "List of all continents affected", "value": ["Europe"]}, "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": ["North Sea"]}, "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": 50.5}, "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": 356.0}, "center_latf": {"name": "Center latitude", "description": "Formatted version of center longitude", "value": "356.0\u00b0E"}, "western_lon": {"name": "Westernmost longitude", "description": "Westernmost longitude affected by event", "value": 354.5}, "eastern_lon": {"name": "Easternmost longitude", "description": "Easternmost longitude affected by event", "value": 360.5}, "southern_lat": {"name": "Southernmost latitude", "description": "Southernmost latitude affected by event", "value": 50.0}, "northern_lat": {"name": "Northernmost latitude", "description": "Northernmost latitude affected by event", "value": 54.5}, "polygons_merged": {"name": "Merged polygon", "description": "Merger or polygons at each time step", "value": {"type": "MultiPolygon", "coordinates": [[[[-4.25, 49.85], [-4.32, 49.82], [-4.47, 49.47], [-5.0, 49.25], [-5.25, 49.35], [-5.5, 49.25], [-6.03, 49.47], [-6.25, 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[-4.68, 51.18], [-4.65, 51.25], [-4.68, 51.32], [-4.75, 51.35], [-5.0, 51.25], [-4.75, 51.15]]]]}}, "IPCC_regions": {"name": "IPCC regions", "description": "List of all IPCC regions affected", "value": ["N.Europe", "West&Central-Europe"]}, "polygons": {"name": "Polygons", "description": "Polygon vertices describing the boundary of the event at each time step", "value": {"2025-09-21T11:30:00.000000000": {"type": "MultiPolygon", "coordinates": [[[[-5.529999999999973, 51.03], [-5.0, 51.25], [-5.529999999999973, 51.47], [-5.75, 52.0], [-5.529999999999973, 52.53], [-5.0, 52.75], [-4.75, 52.65], [-4.680000000000007, 52.68], [-4.649999999999977, 52.75], [-4.75, 53.0], [-4.529999999999973, 53.53], [-4.0, 53.75], [-3.75, 53.65], [-3.680000000000007, 53.68], [-3.5299999999999727, 54.03], [-3.180000000000007, 54.18], [-3.1499999999999773, 54.25], [-3.25, 54.5], [-3.0299999999999727, 55.03], [-2.5, 55.25], [-2.25, 55.15], [-2.0, 55.25], [-1.75, 55.15], [-1.5, 55.25], [-1.25, 55.15], [-1.0, 55.25], 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"value": [10.405214573786793, 9.34015976343403, 10.076426207713553, 10.259982408796077, 10.61853010389541, 10.247128211127404]}, "evo_maxamp": {"name": "Evolution of maximum t2m", "description": "The daily evolution of maximum t2m.", "value": [6.797101593017601, 6.016536966959677, 7.715815480550134, 8.369659678141318, 10.50421803792318, 10.022573089599632]}, "anom_evo_areamean": {"name": "Evolution of mean t2m anomalies", "description": "The daily evolution of mean t2m anomalies.", "value": [-3.107897334857887, -4.049228143137742, -3.172656293231268, -2.693314529898974, -2.7007528539997643, -3.0247467263615513]}, "anom_evo_maxamp": {"name": "Evolution of maximum t2m anomalies", "description": "The daily evolution of maximum t2m anomalies.", "value": [-4.125104486030864, -5.003400989579063, -4.0461035392737585, -3.0253020713460046, -2.761768827362914, -3.341068356118285]}, "anom_scaled_evo_areamean": {"name": "Evolution of mean standardized t2m anomalies", "description": "The daily 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