Biogeochemical data from terrestrial and aquatic ecosystems in a periglacial catchment, West Greenland

Abstract

Abstract. Global warming is expected to be most pronounced in the Arctic where permafrost thaw and release of old carbon may provide an important feedback mechanism to the climate system. To better understand and predict climate effects and feedbacks on the cycling of elements within and between ecosystems in northern latitude landscapes, a thorough understanding of the processes related to transport and cycling of elements is required. A fundamental requirement to reach a better process understanding is to have access to high-quality empirical data on chemical concentrations and biotic properties for a wide range of ecosystem domains and functional units (abiotic and biotic pools). The aim of this study is therefore to make one of the most extensive field data sets from a periglacial catchment readily available that can be used both to describe present-day periglacial processes and to improve predictions of the future. Here we present the sampling and analytical methods, field and laboratory equipment and the resulting biogeochemical data from a state-of-the-art whole-ecosystem investigation of the terrestrial and aquatic parts of a lake catchment in the Kangerlussuaq region, West Greenland. This data set allows for the calculation of whole-ecosystem mass balance budgets for a long list of elements, including carbon, nutrients and major and trace metals. The data set is freely available and can be downloaded from PANGAEA:

Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland

“…Here we present a geochemical data set to study the weathering processes in a historical moraine in a landterminating region of the Greenland Ice Sheet (GrIS). The study site, near Kangerlussuaq, was selected due to logistic considerations and because previous geochemical studies are available on a nearby sandur (Deuerling et al 2018) as well as for the ice sheet and some river systems and lakes of the area (Scholz and Baumann 1997;Anderson et al 2001;Wimpenny et al 2010Wimpenny et al , 2011Ryu and Jacobson 2012;Graly et al 2014;Hawkings et al 2014Hawkings et al , 2015Hindshaw et al 2014;Aciego, Stevenson, and Arendt 2015;Graly, Humphrey, and Harper 2016;Lindborg et al 2016;Rydberg et al 2016;Stevenson et al 2017;Henkemans et al 2018;Deuerling et al 2019). In the period between 2008 and 2013, a collaborative field and modeling study, the Greenland Analogue Project (GAP), was conducted in the Kangerlussuaq area (Claesson Liljedahl et al 2016) by the national nuclear waste management organizations in Sweden (Swedish Nuclear Fuel and Waste Management Company), Finland (Posiva), and Canada (Nuclear Waste Management Organization).…”

Plant Water δD and δ18O of Tundra Species from West Greenland

“…4 and 6). Although there are only two stations reporting precipitation stable isotope data for the whole of West Greenland, and the OIPC estimates are least robust for arctic and Antarctic areas (Bowen and Revenaugh, 2003), it should be noted that the OIPC estimate for July is in excellent agreement with the measurements from summer rain events (Lindborg et al, 2016). That the precipitation value estimated here using plant waters is more negative than other estimates likely reflects a greater utilization by plants (and lakes) of snow or soil frost melt (Oberbauer and Dawson, 1992;Sugimoto et al, 2002Sugimoto et al, , 2003, which accumulates over the winter and has a lower delta value than summer precipitation.…”

“…Deuterium excess values increase with decreasing temperature for both Thule and Grønnedal (IAEA/WMO, 2016). The XW-LMWL intercept also lies within the range of values for winter precipitation events (Lindborg et al, 2016). Second, using this precipitation value and average July climate variables and assuming an equilibrium relationship between water and vapor give atmospheric vapor values of d 18 O = −32.4‰ and dD = −232‰, which are in good agreement with isotope values recently reported for late summer (August) water vapor samples over seawater at the Kangerlussuaq harbor and three lakes in the same study area (Feng et al, 2016).…”

“…2, part B). The xylem water data here clearly comprise a similar LEL, and instead of intersecting it with the GMWL, we are able to utilize precipitation data from the Kangerlussuaq area recently made available by Lindborg et al (2016). The stable isotope values of local snow and rain events form a local meteoric water line (LMWL) for Kangerlussuaq, which is similar to but not the same as the GMWL (Fig.…”

Using ground-penetrating radar, topography and classification of vegetation to model the sediment and active layer thickness in a periglacial lake catchment, western Greenland

“…The result is a 3-D model of sediment thicknesses, sediment types and maximum thicknesses of the active layer, at catchment scale ( ∼ 1-2 km 2 ). Data on meteorological and hydrological conditions and properties of the TBL catchment were published by Johansson et al (2015), and Lindborg et al (2016) published data on biogeochemistry from TBL. These new data on ALT and sediment thickness constitute valuable complementary input data when setting up distributed physically based hydrological and biogeochemical numerical models of the catchment.…”