Hydrography (HY) Iceland is one of 12 themes in the European Location Project (ELF). The purpose of ELF is to create harmonised cross-border, cross-theme and cross-resolution pan-European reference data from national contributions. The goal is to provide INSPIRE-compliant data for Europe. A description of the ELF (European Location Project) is here: http://www.elfproject.eu/content/overview Encoding: INSPIRE version 4

10 year peak flow isolines in cubic metres per second (m3/s) for 100 square kilometre watersheds and 10 year return period

Results of circumpolar assessment of river diatoms, indicating (a) the location of river diatom stations, underlain by circumpolar ecoregions; (b) ecoregions with many river diatom stations, colored on the basis of alpha diversity rarefied to 40 stations; (c) all ecoregions with river diatom stations, colored on the basis of alpha diversity rarefied to 10 stations; (d) ecoregions with at least two stations in a hydrobasin, colored on the basis of the dominant component of beta diversity (species turnover, nestedness, approximately equal contribution, or no diversity) when averaged across hydrobasins in each ecoregion. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 36 - Figure 4-8

The “Sub-basins of the AAFC Watersheds Project – 2013” dataset is a geospatial data layer containing polygon features representing the Standard Drainage Area Classification (SDAC) 2003 defined sub-drainages of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. Canada has eleven major drainage areas which are divided into 164 sub-drainage areas. All drainage areas and sub-drainage areas are named and have an identifying ‘number’. Sub-drainage areas have ‘numbers’ that share a common ‘three-character’ designation. For example, the 05A sub-basin contains stations ‘numbered’ 05AB006 and 05AC007.

Normal Annual Runoff for 1961 - 1990, in mm

Figure 2-2 Arctic freshwater boundaries from the Arctic Council’s Arctic Biodiversity Assessment developed by CAFF, showing the three sub-regions of the Arctic, namely the high (dark purple), low (purple) and sub-Arctic (light purple)

The “Hydrometric Gauging Station Network of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing network line features representing links between hydrometric gauging stations of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. Each line connects a gauging station to its downstream neighbour(s), indicating its drainage direction. This network is a ‘drainage’ network, not a ‘stream’ network. That is, the lines do not in any way portray the actual stream path between stations. In some instances, a lake, for example, an area may have several gauging stations. In such cases, one of the gauging stations is designated the ‘primary’ gauging station for calculation purposes, and to maintain proper hydraulic relationships between gauging stations, where only the primary stations are connected to the downstream portion of the network.

The "Hydrometric Gauging Stations of the AAFC Watersheds Project - 2013" dataset is a geospatial data layer containing point features representing the hydrometric gauging stations of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The gauging stations are sourced from Environment Canada, the United States and Canadian provinces. Additional virtual stations have been generated to address hydrometric structural issues, like river confluences or lake inlets. Attribute information includes station identification, location and associated catchments/basins.

The “Gross and Effective Drainage Area Boundaries of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing line features representing boundaries associated with the ‘incremental gross drainage areas’ of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The project is subdivided by hydrometric gauging station. The maximum area that could contribute runoff to each station, less that of its upstream neighbour(s) is called its ‘incremental gross drainage area’. Two types of boundary are provided: ‘gross’ and ‘effective’. ‘Gross’ boundaries separate adjacent incremental gross drainage areas. ‘Effective’ boundaries delimit, within each incremental gross drainage area, the separation between areas that supply runoff, based on average runoff, from those that don’t.

This layer represents the watershed areas that report to Water Survey of Canada (WSC) and United States Geological Survey (USGS) gauge stations that meet the following criteria for inclusion: at least 10 years or data (with 350 or more days of observations) above the low outlier threshold; less than 20% (by basin drainage area) regulation; a corresponding basin polygon dataset (either supplied or delineated) with a area <15% different than the basin area reported by WSC or USGS; full metadata coverage for the basin (e.g. mean annual precipitation, elevation, etc.); and 1-, 3-, 5-, and -10 day distribution fits that did not overlap for any Average Recurrence Interval’s (ARI) above 2 years. See Bulletin 2020-1-RFFA British Columbia Extreme Flood Project – Regional Flood Frequency Analysis – Technical development report and manual to complete a regional flood frequency analysis.