Moving 6-year analysis of Dissolved Inorganic Nitrogen at Atlantic Sea for each season.

- winter: January-March,

- spring: April-June,

- summer: July-September,

- autumn: October-December

Every year of the time dimension corresponds to the 6-year centred average of each season. 6-year periods span

- from 1988-1993 until 2015-2020 (winter),

- from 1988-1993 until 2015-2020 (spring),

- from 1986-1991 until 2015-2020 (summer),

- from 1984-1989 until 2015-2020 (autumn).

Observational data span from 1984 to 2020.

Depth range (IODE standard depths): -2000.0, -1750, -1500.0, -1400.0, -1300.0, -1200.0, -1100.0, -1000.0, -900.0, -800.0, -700.0, -600.0, -500.0, -400.0, -300.0, -250.0, -200.0, -150.0, -125.0, -100.0, -75.0, -50.0,-40.0, -30.0, -20.0, -10.0, -5.0, -0.0

Data Sources: observational data from SeaDataNet/EMODNet Chemistry Data Network.

Description of DIVA analysis: Geostatistical data analysis by DIVA (Data-Interpolating Variational Analysis) tool. GEBCO 1min topography is used for the contouring preparation. Analyzed filed masked using relative error threshold 0.3 and 0.5 DIVA settings. Correlation length was optimized and filtered vertically and a seasonally-averaged profile was used. Signal to noise ratio was fixed to 1. Logarithmic transformation applied to the data prior to the analysis. Background field: the data mean value is subtracted from the data. Detrending of data: no, Advection constraint applied: no.

Units: umol/l