ArcticGRO Daily River Discharge Data for Arctic Rivers

Version: v20261104
Data through: 2026-11-01 (latest provisional value; end dates differ by station, see stations.csv)
Prepared: 2026-11-04
Contact: Anya Suslova, Woodwell Climate Research Center, asuslova@woodwellclimate.org

Summary

This dataset contains mean daily river discharge for 17 gauging stations on 15 rivers draining to the Arctic Ocean, compiled by the Arctic Great Rivers Observatory (ArcticGRO; https://arcticgreatrivers.org). Discharge is measured by national hydrological agencies in Russia (Roshydromet), the United States (U.S. Geological Survey, USGS) and Canada (Water Survey of Canada, WSC). ArcticGRO compiles these records into one consistent format, combining certified (approved) records with provisional data so that each record is as up to date as possible.

All values are mean daily discharge in cubic metres per second (m³ s⁻¹).

Stations

Full station details (codes, coordinates, drainage area, period of record and completeness) are in stations.csv.

Core ArcticGRO rivers. Discharge for the Yukon, Mackenzie and Ob is measured at the same location as ArcticGRO biogeochemistry sampling. For the Yenisey, Lena and Kolyma, discharge is provided for the gauge closest to the ArcticGRO sampling site. Many publications that use ArcticGRO biogeochemistry data correct for the offset between the discharge and chemistry sampling locations using the approach in Holmes et al. (2012).

River	Station	Station code	Agency
Yukon	Pilot Station	15565447	USGS
Mackenzie	Arctic Red River	10LC014	WSC
Ob	Salekhard	11801	Roshydromet
Yenisey	Igarka	9803	Roshydromet
Lena	Kyusyur	3821	Roshydromet
Kolyma	Srednekolymsk (through 2021)	1801	Roshydromet
Kolyma	Kolymskoe	1802	Roshydromet

Additional rivers (added to ArcticGRO in 2019): Onega (Porog), Northern Dvina (Ust Pinega), Mezen (Malonisogorskoye), Pechora (Ust Tsilma and Oksino), Nadym (Nadym), Pur (Samburg), Olenek (7.5 km downstream of the Buur River mouth), Yana (Yubileinaya) and Indigirka (Indigirsky). Archival data for the full period of record were added for all rivers in 2020.

Files

File	Contents
<River>_<Station>.csv (17 files)	Daily discharge for one station
stations.csv	One row per station: metadata and record summary
README.md	This file

In the GitHub repository the station files are in the data/ folder; on Zenodo all files are at the top level.

Data files are UTF-8, comma-separated, with one header row and one row per calendar day. Each file starts at the station's first day with data; days without data inside the record are kept as rows with NA.

Columns in the station data files

Column	Type	Description
river	text	River name
agency	text	Agency that collected the data: Roshydromet, USGS or Water Survey of Canada. NA when no data for that day
station_code	text	Agency station identifier. NA when no data for that day
station_name	text	Gauging station name (transliterated for Russian stations). NA when no data for that day
date	date	Calendar date, YYYY-MM-DD
discharge_m3s	number	Mean daily discharge, m³ s⁻¹. NA = no data
flag	text	Data status, see below

Columns in stations.csv

Column	Description
river, station_name, station_code, agency	As in the data files
latitude, longitude	Decimal degrees, WGS84; west longitudes are negative
drainage_area_km2	Drainage area upstream of the gauge
core_arcticgro_river	yes for the six core ArcticGRO rivers
file_name	Data file for this station
start_date, end_date	First and last date in the file
n_days_with_data	Number of days with a discharge value
pct_days_missing	Percentage of days between start and end date with NA

Flags

Flag	Meaning
A	Approved: data certified by the responsible hydrological agency
P	Provisional: subject to revision (see below)
NA	No data for that day

Provisional (P) data:

• Yukon: from the USGS National Water Information System (https://waterdata.usgs.gov/nwis).
• Mackenzie: daily discharge calculated from near-real-time transmissions from the WSC gauging station.
• Russian rivers: estimated by the Arctic and Antarctic Research Institute (AARI), St. Petersburg, from near-real-time water stage, river-ice thickness and ice conditions, together with historical stage–discharge relationships and winter correction coefficients. Provisional winter values are usually revised at the end of ice conditions (June–July).

Provisional values are replaced by approved values as agencies release them, so later versions of this dataset may change provisional periods.

Processing and quality control

• Values were compiled from agency records into one common format and unit (m³ s⁻¹). USGS publishes discharge in ft³ s⁻¹; Yukon values were converted (1 ft³ s⁻¹ = 0.0283168 m³ s⁻¹) and rounded to whole numbers.
• In November 2026 the records were screened for isolated one- or two-day spikes and drops, runs of zero values, blank cells, inconsistent flags and inconsistent number precision. Values identified as transcription errors were corrected against the original agency records; values that could not be confirmed were set to NA.
• Rows before each station's first valid value were removed. Missing days within the record are NA.

Known issues

• Pechora at Ust Tsilma, 1980–1990: most daily values (3,365 days) are identical to Pechora at Oksino (station 70827, downstream) and appear to have been filled from that record.
• Yana, 2018-06-02: the provisional peak of 41,280 m³ s⁻¹ is about twice the highest value in any other year and has not been confirmed.
• Values replaced during QC: ten values identified as errors were replaced with the previous day's value and keep their original flag: Kolyma at Srednekolymsk 1934-09-20, 1934-10-20, 1950-05-01 and 1988-02-12; Kolyma at Kolymskoe 2011-12-31; Lena 2023-10-21; Onega 1980-10-06, 1980-10-25 and 1980-11-06; Pechora at Ust Tsilma 1935-05-29.
• Flag sequence: some records (Lena 2012–2021, Northern Dvina 2014–2021, Onega 2017–2021, Pur 2017–2021) switch between A and P within the provisional period.

How to cite

To cite the dataset (all versions; this DOI always resolves to the latest version):

Arctic Great Rivers Observatory (2026). ArcticGRO Discharge Dataset [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.23957360

To cite the exact version you used (recommended in publications, for reproducibility), use that version's DOI from the Zenodo record page, for example:

Arctic Great Rivers Observatory (2026). ArcticGRO Discharge Dataset (Version v20261104) [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.23957361

License

This dataset is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0), https://creativecommons.org/licenses/by/4.0/. When using these data, please cite this dataset and acknowledge the original data providers: Roshydromet, the U.S. Geological Survey and the Water Survey of Canada.

References

Holmes, R. M., McClelland, J. W., Peterson, B. J., Tank, S. E., Bulygina, E., Eglinton, T. I., Gordeev, V. V., Gurtovaya, T. Y., Raymond, P. A., Repeta, D. J., Staples, R., Striegl, R. G., Zhulidov, A. V., & Zimov, S. A. (2012). Seasonal and annual fluxes of nutrients and organic matter from large rivers to the Arctic Ocean and surrounding seas. Estuaries and Coasts, 35, 369–382. https://doi.org/10.1007/s12237-011-9386-6

Version history

Version	Date	DOI	Changes
v20261104	2026-11-04	10.5281/zenodo.23957361	First Zenodo release