Dataset for: Tracking freshwater browning and coastal water darkening from boreal forests to the Arctic Ocean

Opdal, Anders Frugård1 ; Andersen, Tom2 ; Hessen, Dag Olav2 ; Lindemann, Christian1 ; Aksnes, Dag L.1

Published Jul 07, 2022; Updated Jan 18, 2024 on Dryad. https://doi.org/10.5061/dryad.xwdbrv1gq

Data files

Jul 07, 2022 version files 55.94 MB

Catchment_boundaries_Latitude.txt

1.03 MB
Catchment_boundaries_Longitude.txt

1.03 MB
Catchment_Discharge.txt

52.46 MB
Catchments_to_Regions.txt

1.29 KB
Chlorophyll.txt

608.22 KB
Forest.txt

1.45 KB
Lakes_light_absorption.txt

26.97 KB
Particle_tracking_code.txt

1.36 KB
README_Metadata.rtf
322.81 KB
Secchi_and_Salinity.txt

465.86 KB

Feb 10, 2023 version files 137.83 MB

Catchment_boundaries_Latitude.txt

1.03 MB
Catchment_boundaries_Longitude.txt

1.03 MB
Catchment_Discharge.txt

52.46 MB
Catchments_to_Regions.txt

1.29 KB
Chlorophyll.txt

37.38 MB
Forest.txt

1.45 KB
Lakes_light_absorption.txt

26.97 KB
Particle_tracking_code.txt

1.36 KB
README.md
387.83 KB
Salinity.txt

36.95 MB
Secchi.txt

8.58 MB

Mar 06, 2023 version files 54.93 MB

Catchment_boundaries_Latitude.txt

1.03 MB
Catchment_boundaries_Longitude.txt

1.03 MB
Catchment_Discharge.txt

52.46 MB
Catchments_to_Regions.txt

1.29 KB
Lakes_light_absorption.txt

26.97 KB
Particle_tracking_code.txt

1.36 KB
README.md
388.43 KB

Jan 18, 2024 version files 54.58 MB

Catchment_boundaries_Latitude.txt

1.03 MB
Catchment_boundaries_Longitude.txt

1.03 MB
Catchment_Discharge.txt

52.46 MB
Catchments_to_Regions.txt

1.29 KB
Lakes_light_absorption.txt

26.97 KB
Particle_tracking_code.txt

1.36 KB
README.md
40.94 KB

Abstract

The forest cover of Northern Europe has been steadily expanding during the last 120 years. More terrestrial vegetation and carbon fixation leads to more export to surface waters. This may cause freshwater browning, as more degraded plant-litter ends up as chromophoric (coloured) dissolved organic matter. Although most freshwater ultimately drains to coastal waters, the link between freshwater browning and coastal water darkening is poorly understood. Here, we explore this relationship through a combination of centennial records of forest and coastal water clarity, contemporary optical measurements in lakes and coastal waters, as well as an ocean drift model. We suggest a link between forest cover in Northern Europe and coastal water clarity in the Baltic, Kattegat and Skagerrak Sea and show how brown coloured freshwater from Northern European catchments can dictate coastal water clarity across thousands of kilometres, from the Baltic lakes to the Barents Sea.

README

Metadata template[1] for datasets of L&O-Letters articles

* *

Table 1. Description of the fields needed to describe the creation of your dataset.

Title of dataset	Dataset for article " Tracking freshwater browning and coastal water darkening from boreal forests to the Arctic Ocean"
URL of dataset	https://doi.org/10.5061/dryad.xwdbrv1gq
Abstract	The forest cover of Northern Europe has been steadily expanding during the last 120 years. More terrestrial vegetation and carbon fixation leads to more export to surface waters. This may cause freshwater browning, as more degraded plant-litter ends up as chromophoric (coloured) dissolved organic matter. Although most freshwater ultimately drains to coastal waters, the link between freshwater browning and coastal water darkening is poorly understood. Here, we explore this relationship through a combination of centennial records of forest and coastal water clarity, contemporary optical measurements in lakes and coastal waters, as well as an ocean drift model. We suggest a link between forest cover in Northern Europe and coastal water clarity in the Baltic, Kattegat and Skagerrak Sea and show how brown coloured freshwater from Northern European catchments can dictate coastal water clarity across thousands of kilometres, from the Baltic lakes to the Barents Sea.
Keywords	TerraCoast, CDOM, coastal darkening, greening, browning, forest cover, light attenuation, freshwater, Baltic Sea, North Sea, Skagerrak, Norwegian Coastal Water
Lead author for the dataset	Anders Frugård Opdal
Title and position of lead author	Reseracher and Principle investigator
Organization and address of lead author	Thormøhlens gate 53B, 5006 Bergen, Norway
Email address of lead author	Anders.opdal@uib.no
Additional authors or contributors to the dataset	Tom Andersen, Dag O. Hessen, Christian Lindemann, and Dag L. Aksnes
Organization associated with the data	University of Bergen, University of Oslo, Wageningen University and Research, ICES, The Norwegian Water Resources and Energy Directorate, (NVE), Norwegian Environment Agency, Baltic Nest Institute, NOAA, the Swedish Meteorological and Hydrological Institute, Marine Scotland,
Funding	Anders Frugård Opdal, TerraCoast, the Research Council of Norway, funding-ID 287490
License	*CC0*
Geographic location – verbal description	The Baltic Sea, North Sea, Skagerrak, Kattegat, and Norwegian Coastal Waters, as well land areas draining to these. The latter includes whole, or parts of, the following countries: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czechia, Germany, Denmark, Netherlands, Belgium, Luxembourg, France, Switzerland and the UK.
Geographic coverage bounding coordinates	Latitude: 45 °N – 72 °N
Time frame - Begin date	Jan 1st 1900
Time frame - End date	Dec 31st 2021
General study design	The study is based on re-analyses of previously collected and published data. Links to appropriate data collection descriptions are provided in below Methods description and Table 3. Data provenance.
Methods description	The forest cover data was retrieved from the Historic Land Dynamics Assessment (HILDA) database provided by the Department of Geoinformation Science and Remote Sensing, Wageningen University, Netherlands (http://www.geo-informatie.nl/fuchs003/#), and the FAO Global Forest Resources Assessment database (https://fra-data.fao.org/WO/fra2020/home/). For Norway, which is not part of the EU, forest cover was drawn from Norway’s national forest inventory available at https://landsskog.nibio, and described in https://doi.org/10.1186/s40663-020-00261-0
Laboratory, field, or other analytical methods	* *
Taxonomic species or groups	* *
Quality control	* *
Additional information	* *

Table 2. Data dictionary: description of the variables (i.e., columns) in EACH dataset. You must provide sufficient detail for another user to understand and use the data. If there are 10 variables (i.e., columns) in the dataset, then there should be 10 rows in this table that describe each column. Be sure to include all relevant information for your dataset, including the unique identifiers for your dataset or system, dates, replicate numbers, latitude and longitude of sampling locations, etc.

Dataset filename: Forest.txt

Dataset description: Decadal estimates of forest cover in whole or parts of countries draining to the Baltic Sea, the North Sea, or the Skagerrak Sea. This is a 2D matrix with 1 reference column ( col 1) and 1 reference row (row 1)

Column name	Description	Units	Code explanation	Data format	Missing data code
Country/year	Country refer to column 1
Country/year	Year refer to the top row and relates to the 2D matrix values in columns 2-14	* *	* *	* *	* *
Matrix	Forest cover	km2

Dataset filename: Secchi.txt

Dataset description: Secchi disk depth measurements in the Baltic Sea, Kattegat, Skagerak and North Sea

Column name	Description	Units	Code explanation	Data format	Missing data code
Year	Year	* *	* *	* *	* *
Month	Month in year
Day	Day of month
Lat	Latitude	°N
Lon	Longitude	°E
Secchi	Secchi disk depth	m

Dataset filename: Salinity.txt

Dataset description: S*alinity measurements in the Baltic Sea, Kattegat, Skagerak and North Sea*

Column name	Description	Units	Code explanation	Data format	Missing data code
Year	Year	* *	* *	* *	* *
Month	Month in year
Day	Day of month
Lat	Latitude	°N
Lon	Longitude	°E
Salinity	Salinity	psu

Dataset filename: Chlorophyll.txt

Dataset description: Chlorophyll a concentrations in the Baltic Sea, Kattegat, Skagerak and North Sea

Column name	Description	Units	Code explanation	Data format	Missing data code
Year	Year
Month	Month in year	* *	* *	* *	* *
Day	Day of month
Lat	Latitude	°N
Lon	Longitude	°E
Chla	Chlorophyll a concentration	mg m-3
Sample	Type of method used to obtain chlorophyll a concentration		1 = direct measurement

Dataset filename: Lakes_light_absorption.txt

Dataset description: Non-phytoplankton spectral light absorption in 13 lakes in Western Norway. This is a 2D matrix with reference 7 columns (col 1-7) and reference 1 row (row 1).

Column name	Description	Units	Code explanation	Data format	Missing data code
Lake name	Name of lake	* *	* *	* *	* *
Lake ID	Numeric identifier
Lat	Latitude	°N
Lon	Longitude	°E
Year	Year
Month	Month in year
Day/wavelength	Day
Day/wavelength	Wavelength is denoted in the top row and relates to the 2D matrix values in columns 8-358	nm
Matrix	Light absorption	m-1

Dataset filename: Catchment_discharge.txt

Dataset description: Water discharge from catchment areas draining to the Norwegian Coastal Waters between Skagerrak and the Barents Sea

Column name	Description	Units	Code explanation	Data format	Missing data code
Year	Year	* *	* *	* *	* *
Month	Month in year	* *	* *	* *
Day	Day of month	* *	* *	* *
Catchm.	Catchment ID	* *	See Catchment boundary files for geographical locations	* *
Discharge	Water discharge	m3 s-1	* *	* *

Dataset filename: Catchment_boundaries_Latitude.txt

Dataset description: Latitudinal boundaries for the catchments draining to the Norwegian Coastal Waters between Skagerrak and the Barents Sea. This is a 2D matrix with 1reference column (col 1)

Column name	Description	Units	Code explanation	Data format	Missing data code
Catchment/Latitude	Catchment ID refers to column 1	* *	* *	* *	* *
Catchment/Latitude	Latitudes for each catchment	°N

Dataset filename: Catchment_boundaries_Longitude.txt

Dataset description: Longitudinal boundaries for the catchments draining to the Norwegian Coastal Waters between Skagerrak and the Barents Sea. This is a 2D matrix with 1 reference column (col 1)

Column name	Description	Units	Code explanation	Data format	Missing data code
Catchment/Longitude	Catchment ID refer to column 1	* *	* *	* *	* *
Catchment/Longitude	Longitudes for each catchment	°E

Dataset filename: Catchments_to_regions.txt

Dataset description: List of catchments and the region to which they belong

Column name	Description	Units	Code explanation	Data format	Missing data code
Catchm.	Catchment ID	* *	* *	* *	* *
Region	Region ID

Table 3. Data provenance

If you used data derived from other sources, provide the information here so future users know where the data came from.

Dataset title	Dataset DOI or URL	Creator (name & email)
Forest.txt (1900-2010)	http://www.geo-informatie.nl/fuchs003/#	Richard Fuchs
Forest.txt (2010-2020)	https://fra-data.fao.org/WO/fra2020/home/.	FAO
Forest.txt (Norway)	https://landsskog.nibio.no/	Aksel Granhus
Secchi.txt (1903-2021)	https://data.ices.dk	Hjalte Parner, hjalte@ices.dk
Secchi.txt (1967-2021)	https://www.smhi.se/data	Emma Rova, Shark@smhi.se
Secchi.txt (1979-2021)	https://vannmiljo.miljodirektoratet.no/	Norwegian Environmental Agency
Secchi.txt(1903-1998)	(https://www.ices.dk/data/dataset-collections/Pages/Secchi-Disc-Archive.aspx)	Thorkild Aarup
Secchi.txt (1903-1990)	https://www.ncei.noaa.gov/products/world-ocean-database	Tim P. Boyer. NCEI.Services@noaa.gov
Salinity.txt (1903-2021)	https://data.ices.dk	Hjalte Parner, hjalte@ices.dk
Salinity.txt (1903-2021)	https://www.smhi.se/data	Emma Rova, Shark@smhi.se
Salinity.txt (1979-2021)	https://vannmiljo.miljodirektoratet.no/	Norwegian Environmental Agency
Salinity.txt (1965-2021)	https://nest.su.se	Bo Gustafsson bo.gustafsson@su.se
Chlorophyll.txt (1961-2021)	https://data.ices.dk/)	Hjalte Parner, hjalte@ices.dk
Chlorophyll.txt (1970-2021)	https://www.smhi.se/data	Emma Rova, Shark@smhi.se
Chlorophyll.txt (1979-2021)	https://vannmiljo.miljodirektoratet.no/	Norwegian Environmental Agency
Chlorophyll.txt (1965-2021)	https://nest.su.se	Bo Gustafsson bo.gustafsson@su.se
Chlorophyll.txt (PCI, 1949-2017)	https://doi.org/10.7487/2019.88.1.1177	David Johns
Chlorophyll.txt (CellCount, 1912, 1946)	https://doi.org/10.1111/gcb.14810	Anders F. Opdal, anders.opdal@uib.no
Lakes_light_absorption.txt	https://doi.org/10.1007/s10021-014-9776	Tom Andersen
Catchment_discharge.txt	https://sildre.nve.no/map	Stein Beldring
Catchment_boundaries_Latitude.txt	https://temakart.nve.no/tema/nedborfelt	The Norwegian Water Resources and Energy Directorate
Catchment_boundaries_Longitude.txt	https://temakart.nve.no/tema/nedborfelt	The Norwegian Water Resources and Energy Directorate

Scripts/code (software) – OPTIONAL

It is recommended that you also provide your scripts along with your data, although it is not required at this time in our journal.

File name	Description	Scripting language
Particle_tracking_code.txt	Code used to run the OpenDrift Lagrangian particle tracking	Python

Notes and Comments:

**[1]* This document liberally borrows from a similar document provided by the Environmental Data Initiative*

Dataset for: Tracking freshwater browning and coastal water darkening from boreal forests to the Arctic Ocean

Data files

Abstract

README

Methods

Works referencing this dataset