Detailed water quality parameters, including methane concentrations and isotopic composition, for groundwater springs discharging from open system pingos in Adventdalen, Svalbard (2014-2017)

Adventdalen is a medium-sized (513 km^2) catchment in continuous permafrost zone of central Spitsbergen. It has 11.7 % glacier cover, a large flat valley floor comprised of uplifted, glaciomarine sediments, covered in the lower part by a veneer of aeolian sediments up to 4 m thick. The geology of the catchment is dominated by sandstones, shales and carbonates. There are a series of five open system pingos that have formed in the valley floor following uplift of the valley bottom over the last 10000 years. This has caused permafrost aggradation in former marine sediments which are up to 60 m thick. During the formation of this new permafrost, high pressure caused expulsion of groundwaters below, resulting in their upward migration. Freezing of the groundwaters as they reached the ground surface caused expansion and thus formation of the pingo. However, freezing no longer occurs at four of the five pingos, meaning that the groundwaters now discharge at the surface. Samples of the emerging groundwaters were collected every March/April, but also opportunistically during summer months, provided the sites weren't flooded. Analysis of major ions (by ion chromatography), minor constituents (trace metals by inductively coupled plasma mass spectroscopy (ICP-MS) and silica by colorimetric analysis) and gases (O2, CO2 and CH4) were undertaken. Funding was provided by the Joint Programming Initiative (JPI-Climate Topic 2: Russian Arctic and Boreal Systems) Award No. 71126, distributed to Principal Investigator, Andrew Hodson (then of University of Sheffield) via NERC grant NE/M019829/1.