Micromolar Nutrient concentration profiles from the long-term time series at Station L4 in the Western English Channel from 2000 to 2022.

Results are reported for the analysis of water samples taken from the L4 long‐term sampling station (50°15.0'N;04°13.0'W) situated off Plymouth on the south‐west coast of England, United Kingdom. The analyses are reported for Nitrate+Nitrite, Nitrite, Silicate and Phosphate concentrations. The dataset begins in 2000 and runs through till end of 2022, and the data are an ongoing time series. In the early years the samples were taken and frozen to be batch analysed at a later date. Since 2007 the site visits have been on a more regular weekly sampling protocol and there are at times both filtered and unfiltered sample results. A classical nutrient water column concentration picture is seen of generally summer nutrient depletion and with higher winter concentrations of Nitrate, Silicate and Phosphate.