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

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 water level data comes from the groundwater monitoring network of Yukon (Canadian territory). Each well in the observation network is equipped with a hydrostatic pressure transducer and a temperature sensor connected to a data logger. A second pressure transducer located above the water surface allows for adjusting the water level according to atmospheric pressure variations. The time series refers to the level below which the soil is saturated with water at the site and at the time indicated. The water level is expressed in meters above sea level (MASL). The dataset consists of a general description of the observation site including; the identifier, the name, the location, the elevation and a series of numerical values designating the water levels at a defined date and time of measurement.

The "Areas of Non-Contributing Drainage within Total Gross Drainage Areas of the AAFC Watersheds Project - 2013" dataset is a geospatial data layer containing polygon features representing the areas within the “total gross drainage areas” of each gauging station of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project that DO NOT contribute to average runoff. A “total gross drainage area” is the maximum area that could contribute runoff for a single gauging station – the “areas of non-contributing drainage” are those parts of that “total gross drainage area” that DO NOT contribute to average runoff. For each “total gross drainage area” there can be none to several unconnected “areas of non-contributing drainage”. These polygons may overlap with those from other gauging stations’ “total gross drainage area”, as upstream land surfaces form part of multiple downstream gauging stations’ “total gross drainage areas”.

The “Gross and Effective Drainage Areas for Hydrometric Gauging Stations of the AAFC Watersheds Project - 2013” dataset is a table that provides the calculated gross and effective drainage areas associated with the hydrometric gauging stations of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. Areas are provided in square kilometres. ‘Gross drainage’ describes the total area of a catchment. ‘Effective drainage’ describes areas that are expected to contribute to an average runoff.

The “Incremental Effective Drainage Areas of the AAFC Watersheds Project– 2013” dataset is a geospatial data layer containing polygon features representing the portions of each incremental gross drainage area of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project that could be expected to contribute to surface runoff under average runoff conditions. An ‘incremental gross drainage area’ is a hydrometric gauging station's drainage basin, less that of the next upstream gauging station(s)’. ‘Effective drainage’ occurs in areas that are expected to supply surface runoff in an average runoff.

Figure 3-2 Long-term water temperature trends (1970–2017) for the Utsjoki Nuorgam station in the River Tana (69°N in Finland). The diagram shows the number of days per year with a mean temperature exceeding 5°C. The data show that from 1995 to 2017, this indicator increased by over 0.5 days per year. Data source: Finnish Meteorological Institute. State of the Arctic Freshwater Biodiversity Report - Chapter 3 - Page 15 - Figure 2-1

Rarefied alpha diversity of river (a) diatoms from benthic samples, (b) benthic macroinvertebrates, and (c) fish in ecoregions across North America. State of the Arctic Freshwater Biodiversity Report - Chapter 5- Page 84 - Figure 5-1

The "Total Gross Drainage Areas of the AAFC Watersheds Project - 2013" dataset is a geospatial data layer containing polygon features representing the maximum area that could contribute surface runoff (total gross drainage areas) for each gauging station of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. These polygons overlap as upstream land surfaces form part of multiple downstream gauging stations’ total gross drainage areas. Drainage area includes all land whose surface runoff contributes to the same drainage outlet or gauging station. Many gauging stations share the same headwaters, thus the overlapping areas (or polygons). The majority of the drainage areas in this dataset have shared areas.

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.