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Long-term hydroclimate monitoring in Linnédalen, western Spitsbergen provides a baseline for understanding climate and environmental change in the rapidly warming 21st century climate in Svalbard. Monitoring watershed and climatological processes also provides the means for directly interpreting the annually resolved sedimentation record (varves) in proglacial Linnévatnet, which in turn, will allow for an understanding of the current hydroclimatic regime in a long-term context. Related sediment core data were submitted by our collaboration partners at the University of Massachusetts, Amherst. An automated weather station, snow depth and stream water temperature sensors, time-lapse cameras, and moorings in Linnévatnet have been deployed since 2003 in the 31 square kilometer (km2) catchment of Linnédalen. This project (2016-2023) follows hydroclimate studies initiated during the National Science Foundation - Office of Polar Programs (NSF-OPP) sponsored Svalbard Research Experience for Undergraduates (REU) which ran from 2003 to 2013 archived and research and teaching in Linnédalen while the project was affiliated with the University Centre in Svalbard 2016-2022. Data from the earlier phase of the Linnedalen monitoring project includes weather station measurements, time lapse photography, and student theses and reports was archived in the Arctic Data Center and can be found here: https://arcticdata.io/catalog/view/urn:uuid:1b96e994-20a1-4445-a327-3256c040034f 

Abstract Northern Arizona University, Flagstaff, Arizona, USA, recently installed a MIni CArbon DAting System (MICADAS) with a gas interface system (GIS) for determining the¹⁴C content of CO₂gas released by the acid dissolution of biogenic carbonates. We compare 48 paired graphite, GIS, and direct carbonate¹⁴C determinations of individual mollusk shells and echinoid tests. GIS sample sizes ranged between 0.5 and 1.5 mg and span 0.1 to 45.1 ka BP (n = 42). A reduced major axis regression shows a strong relationship between GIS and graphite percent Modern Carbon (pMC) values (m = 1.011; 95% CI [0.997–1.023], R²= 0.999) that is superior to the relationship between the direct carbonate and graphite values (m = 0.978; 95% CI [0.959-0.999], R²= 0.997). Sixty percent of GIS pMC values are within ±0.5 pMC of their graphite counterparts, compared to 26% of direct carbonate pMC values. The precision of GIS analyses is approximately ±70¹⁴C yrs to 6.5 ka BP and decreases to approximately ±130¹⁴C yrs at 12.5 ka BP. This precision is on par with direct carbonate and is approximately five times larger than for graphite. Six Plio-Pleistocene mollusk and echinoid samples yield finite ages when analyzed as direct carbonate but yield non-finite ages when analyzed as graphite or as GIS. Our results show that GIS¹⁴C dating of biogenic carbonates is preferable to direct carbonate¹⁴C dating and is an efficient alternative to standard graphite¹⁴C dating when the precision of graphite¹⁴C dating is not required. 

The ability to understand and predict environmental changes in Svalbard is highly dependent on the availability of detailed and long-term records of baseline environmental data from a regional network across the archipelago. The Kapp Linné region provides a strategic location for a dedicated long-term environmental observatory in the western coastal region of the Nordenskiöldland Peninsula. This region is greatly influenced by the Atlantic High Arctic maritime climate regime (Eckerstorfer and Christiansen 2011) with higher mean annual air temperature and greater precipitation than the more continental interior regime in central Spitsbergen (Humlum 2002). With the recent intensified Atlantification of the northern Barents Sea (Nilsen et al. 2016; Barton et al. 2018), environmental monitoring studies along the Nordenskiöldland coast may help to serve as an early warning system for climate change and accompanying environmental responses across the Svalbard archipelago. 

Review of hydroclimate, limnology, periglacial geomorphology and permafrost monitoring in the App Linne-Gronfjorden region of Svalbard, and recommendations for future research. 

ABSTRACT The direct carbonate procedure for accelerator mass spectrometry radiocarbon (AMS 14 C) dating of submilligram samples of biogenic carbonate without graphitization is becoming widely used in a variety of studies. We compare the results of 153 paired direct carbonate and standard graphite 14 C determinations on single specimens of an assortment of biogenic carbonates. A reduced major axis regression shows a strong relationship between direct carbonate and graphite percent Modern Carbon (pMC) values (m = 0.996; 95% CI [0.991–1.001]). An analysis of differences and a 95% confidence interval on pMC values reveals that there is no significant difference between direct carbonate and graphite pMC values for 76% of analyzed specimens, although variation in direct carbonate pMC is underestimated. The difference between the two methods is typically within 2 pMC, with 61% of direct carbonate pMC measurements being higher than their paired graphite counterpart. Of the 36 specimens that did yield significant differences, all but three missed the 95% significance threshold by 1.2 pMC or less. These results show that direct carbonate 14 C dating of biogenic carbonates is a cost-effective and efficient complement to standard graphite 14 C dating.