Fjords play a pivotal role in the Arctic, for both the natural world and human societies. It is therefore of the utmost importance that the key parametres of these systems be monitored and quantified in order to better manage them. The collection of temperature and salinity data for many Arctic fjords is well documented, but data for other values, like light availability, are scarce. It is to address this shortcoming that this dataset has been created. Herein one may find data for the surface PAR, Kd, and bottom PAR of seven well studied and representative fjords throughout the European Arctic. The three PAR variables were created via remotely sensed estimates of surface irradiance and turbidity. This output was then mapped to the highest resolution bathymetry data available (~ 50 - 200 m grid) to create a high resolution output. All of the PAR variables are available as overall global averages, monthly climatologies, and annual averages for all months when light is present (March - October). The bottom PAR data are also available as monthly averages per year, making these data the majority of the volume of the dataset. An R package 'FjordLight' has been developed to aid in the access and handling of these data, and their applicability is demonstrated in an ESSD publication.

FjordLight,Satellite data collected between 2003 and 2022 (SeaWiFS/ MODIS/ MERIS/ VIIRS) in conjunction with IBCAO gridded bathymetry data (200 m) and Norwegian mapping authority data (50-150 m) are used to estimate the irradiance reaching the bottom of a series of representative EU Arctic fjords, 2003-2022. This zip file contains seven NetCDF files, one for each of the seven fjords covered by this dataset.The sites are:disko.nc = Disko Bay (Greenland)is.nc = Isfjorden (Svalbard)kong.nc = Kongsforden (Svalbard)nuup,nc = Nuup Kangerlua (Greenland)por.nc = Porsangerfjorden (Norway)stor.nc = Storfjorden (Sbalbard)young.nc = Young Sound (Greenland)The structure of the NetCDF files is identical, and documented internally. Note that the lon/lat for each site are now available at the top level of the NetCDF files as 'site_average_longitude' and 'site_average_latitude'. The three main data layers available are surface PAR (available light at the waters surface), Kd (extinction coefficient of light as it moves through the water column), and bottom PAR (amount of light reaching the seafloor). These data are available on a ~ 50 - 200 m grid, depending on the resolution of the available bathymetry data. Each of these variables, at the same spatial resolution, are available along three time dimensions. A single global average, monthly climatologies (i.e. 12 average values), and annual averages from 2003 - 2022. The bottom PAR are also available monthly per year, so are by far the largest amount of data within the files.