DOI: 10.4211/hs.86117a5f36cc4b7c90a5d54e18161c91
title: LamaH-Ice: LArge-SaMple DAta for Hydrology and Environmental Sciences for Iceland

description: LamaH-Ice (LArge-SaMple DAta for Hydrology and Environmental Sciences for Iceland) is a large-sample hydro-meteorological dataset for Iceland. The dataset includes daily and hourly hydro-meteorological timeseries, including observed streamflow, and catchment characteristics for 107 river basins in Iceland. The catchment characteristics describe the topographic, hydroclimatic, land cover, vegetation, soils, geological and glaciological attributes of the river catchments, as well as the human influence on streamflow in the catchments. LamaH-Ice conforms to the structure of existing large-sample hydrology datasets and includes most variables offered in these datasets, as well as additional information relevant to cold-region hydrology, e.g., timeseries of snow cover, glacier mass balance and albedo. A large majority of the watersheds in LamaH-Ice are not subject to human activities, such as diversions and flow regulations. The dataset is described in detail in a paper in the journal "Earth System Science Data" (ESSD - https://doi.org/10.5194/essd-2023-349). The code used to assemble the dataset is available in folder "F_appendix" in the dataset as well as on GitHub (https://github.com/hhelgason/LamaH-Ice). 

We offer two downloadable files for the LamaH-Ice dataset: 1) Hydrometeorological time series with both daily and hourly resolutions (30 GB after decompression) and 2) Hydrometeorological time series with daily resolution only (2 GB). Other than the temporal resolution, there are no differences between the two downloadable files. This HydroShare resource also hosts the "LamaH-Ice Caravan extension" (1 GB), which complements the "Caravan - A global community dataset for large-sample hydrology" Caravan dataset (Kratzert et al., 2023). The data is formatted in the same manner as the data currently existing in Caravan. To process the Caravan extension, the following guide was used: https://github.com/kratzert/Caravan/wiki/Extending-Caravan-with-new-basins. Some features, e.g. hourly atmospheric and streamflow series, glacier mass balance and MODIS timeseries data are thus only available in the LamaH-Ice dataset.

Data disclaimer: The Icelandic Meteorological Office (IMO) and the National Power Company of Iceland (NPC) own the data from most streamflow gauges in the dataset. The streamflow data is published on Hydroshare with permission of all data owners. Neither we nor the provider of the streamflow dataset can be liable for the data provided. The IMO and the NPC reserve the rights to retrospectively check and update the streamflow timeseries at any time, and these changes will not be reflected in this published dataset. If up-to-date data is needed, users are encouraged to contact the IMO and the NPC.

License: The streamflow data is subject to the CC BY-NC 4.0 (creativecommons.org/licenses/by-nc/4.0/). The streamflow data cannot be used for commercial purposes. All data except for the streamflow measurements are subject to the CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/). Users can share and adapt the dataset only if appropriate credit is given (the ESSD data description paper is cited, the version of the dataset and all data sources are listed which are declared in the folder "Info") and any changes are clearly indicated, and a link to the original license is provided.

Updates since the HydroShare repository was first created on August 18, 2023:
May 31, 2024:
•	Streamflow series were corrected (replaced) for gauges with IDs 31, 70 and 72, and hydrological signatures and water balance files recalculated using the corrected streamflow series. In the Caravan extension, gauges 43 and 51 were also corrected.
March 12, 2024:
Dataset Revision: In line with the ESSD manuscript revision, significant updates have been made. For a detailed list, visit https://doi.org/10.5194/essd-2023-349-AC1. Key changes include:
•	A timeseries for reference ET has been computed using RAV-II reanalysis meteorological timeseries.
•	Climate indices recalculated with RAV-II reanalysis; ERA5-Land indices remain under an "_ERA5L" suffix.
•	Hydrological signatures are now derived from RAV-II reanalysis precipitation.
•	Standardized .csv column separators to semicolons.
•	Enhanced metadata for all shapefiles.
•	Added attributes (g_lon, g_lat, g_frac_dyn, g_area_dyn) to the dataset.
•	Reordered catchment attributes table columns for consistency with the LamaH-Ice paper.
•	Corrected ERA5-Land reanalysis errors for shortwave and longwave flux timeseries.
•	Streamflow series were corrected for gauges with IDs 43 and 51 (in LamaH, not Caravan extension)
February 22, 2024
•	Caravan Extension Fix: Corrected latitude and longitude mix-up.
October 1, 2023
•	GeoPackages added as an alternative to shapefiles, readme files added in all subfolders for guidance.