Monthly measurements of total particulate matter and its organic and inorganic compartment in a sub-Arctic fjord, Ramfjord in Tromsø, Norway between September 2020 and August 2021

Fjord water was collected on a monthly basis between September 2020 and August 2021 from 5m and 30m depth in a sub-Arctic fjord (Ramfjorden, Tromso, Norway) with a GoFlo (General Oceanics). For the determination of in situ total particulate matter (TPM), particulate inorganic matter (PIM) and particulate organic matter (POM), between 1000-2000ml was filtered in triplicates through pre-combusted and pre-weighted GF/F filters (0.7 mum, Whatman). After filtration, the filters were placed on a pre-combusted aluminum dish and dried for 24h at 60C in a drying oven. The dry weight was measured on a microscale (Mettler-Toledo MX5) to obtain the weight of TPM, and subsequently combusted in the muffle oven at 450C for 7 h. Finally, the samples were weighed again in order to obtain the weight of the remaining inorganic material on the filters. POM was calculated from the difference between the dry weight (TPM) and the combusted weight (PIM) of the material.