This data release includes sensor data collected from Conductivity Temperature Depth (CTD) casts during a field campaign to Kongsfjorden in July 2024 as part of the NERC funded SiCLING project (Silicon Cycling in Glaciated Environments), led by Dr. K. Hendry from the British Antarctic Survey. Thirteen CTD casts were carried out in a transect along the fjord. Funding: NERC Pushing the Frontiers grant SiCLING (NE/X014819/1).

Glacier meltwater supplies a significant amount of silicon (Si) and iron (Fe) sourced from weathered bedrock to downstream ecosystems. However, the extent to which these essential nutrients reach the ocean is regulated by the nature of the benthic cycling of dissolved Si and Fe within fjord systems, given the rapid deposition of reactive particulate fractions at fjord heads. The dataset is used to examine the benthic cycling of the two nutrients at Patagonian fjord heads through geochemical analyses of sediment pore waters and reaction-transport modeling for Si. The dataset contains: (i) pore water redox-sensitive nitrate (NO3-) and dissolved manganese (DMn) concentration data, nutrient dissolved silicon (DSi) and iron (DFe) concentration and isotope data (delta30 Si, delta56 Fe); (ii) mild alkaline leachable (Si-Alk) and acid leachable (Si-HCl) sediment silica content and isotope data; and (iii) reaction transport model output for the benthic cycling of Si. The pore water and sediment samples were collected from four sites: SJ (48.228o S, 73.502o W, 106 m depth), SH (47.679 S, 73.715 W, 203 m depth), SP (48.179 S, 73.347 W, 248 m depth) and SB (47.787 S, 73.610 W, 151 m depth) in the Baker-Martinez Fjord Complex on the research vessel Sur-Austral in February 2017. Funded by NERC-CONICYT grant NE/P003133/1-PII20150106.

The ICEBERGS project aimed to understand the impact of retreating coastal glaciers upon benthic marine ecosystems along the West Antarctic Peninsula (WAP). This was a collaboration project between University of Exeter, the British Antarctic Survey, Universidad Catololica de Santiago de Concepcion and Bangor University. During three research cruises (JR17001, JR18003 and JR19002) between 2017 and 2020, biological specimens along with other scientific data and samples were collected from three coastal fjords (i.e. Marian Cove, Borgen Bay and Sheldon Cove). The biological samples were collected using mainly a benthic Agassiz trawl and some using a Hamon grab and they were either preserved in ethanol or dry. Funding: The funding for this grant was provided from NERC and from CONICYT Chile (NERC-CONICYT; NE/P003087/1).