EOWetMet: Seasonal Inundation Dataset for NWT and Sweden (2021-2025)

The EOWetMet Seasonal Inundation Dataset (2021-2025) provides a seasonal record of surface water and inundation across two 500 km × 500 km Arctic study areas in the Northwest Territories, Canada, and northern Sweden, for the period 2021 to 2025. The dataset forms part of the EOWetMet Community Product Database and was developed to improve the spatial and temporal characterisation of wetlands and lakes at high resolution, in support of bottom-up methane emission modelling and a broad range of Arctic science applications. Inundation estimates were derived following Huang et al. (2022) and implemented using a two-step classification framework applied to Sentinel-1 C-band SAR time series data processed within Google Earth Engine. The final value for each pixel and seasonal window represents the percentage of valid Sentinel-1 acquisitions during which that pixel was classified as inundated, expressed on a scale of 0 to 100. Four seasonal compositing windows are produced per year, yielding 20 seasonal inundation layers per study area. Products are delivered at 10 m spatial resolution as individual GeoTIFFs (zipped) and as a NetCDF with one inundation layer per season from 2021 to 2025. Each layer represents seasonal inundation derived from three-month observations. During NetCDF creation, these three-month seasonal windows are represented as centre date of the corresponding seasonal window:January 1 – April 1 (Winter–Spring) – Centre Date is 15 FebruaryApril 1 – July 1 (Spring–Summer) – Centre Date is 16 MayJuly 1 – October 1 (Summer–Fall) – Centre Date is 16 AugustOctober 1 – January 1 (Fall–Winter) – Centre Date is 16 NovemberThe study areas are located as follows:NWT: Top Left - 69°45'49.62"N, 138°30'22.94"W Top Right – 70°25'37.28"N, 125°29'17.32"WBottom Right – 65°56'45.22"N, 125° 2'42.60"WBottom Left – 65°24'50.88"N, 135°50'38.95"WCentre - 67°45'59.43"N, 130°45'28.96"WSweden: Top Left – 68°10'47.21"N, 11°41'4.11"ETop Right – 68°54'38.40"N, 24°39'48.56"EBottom Right – 63°57'26.17"N, 25° 6'6.50"EBottom Left – 63°22'22.70"N, 14°19'44.28"ECentre - 66° 8'51.24"N, 19°45'36.16"EReferences--------------------------------------Huang, C., Smith, L.C., Kyzivat, E.D., Fayne, J.V., Ming, Y., Spence, C., 2022. Tracking transient boreal wetland inundation with Sentinel-1 SAR: Peace-Athabasca Delta, Alberta and Yukon Flats, Alaska. GIScience & Remote Sensing 59, 1767–1792. https://doi.org/10.1080/15481603.2022.2134620