Holocene ice wedge formation in the Eureka Sound Lowlands, high Arctic Canada

2021 ◽  
pp. 1-13
Author(s):  
Kethra Campbell-Heaton ◽  
Denis Lacelle ◽  
David Fisher ◽  
Wayne Pollard
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Numerical Simulations ◽  
High Arctic ◽  
Desert Environment ◽  
Peat Accumulation ◽  
Polar Desert ◽  
Molar Ratios ◽  
Air Temperatures ◽  
Ice Wedge

Abstract Ice wedges are ubiquitous periglacial features in permafrost terrain. This study investigates the timing of ice wedge formation in the Fosheim Peninsula (Ellesmere and Axel Heiberg Islands). In this region, ice wedge polygons occupy ~50% of the landscape, the majority occurring below the marine limit in the Eureka Sound Lowlands. Numerical simulations suggest that ice wedges may crack to depths of 2.7–3.6 m following a rapid cooling of the ground over mean winter surface temperatures of −18°C to −38°C, corresponding to the depth of ice wedges in the region. The dissolved organic carbon (DOC)/Cl molar ratios suggest that the DOC in the ice wedges is sourced from snowmelt and not from leaching of the active layer. Based on 32 14CDOC measurements from 15 ice wedges, the wedges were likely developing between 9000–2500 cal yr BP. This interval also corresponds to the period of peat accumulation in the region, a proxy of increased moisture. Considering that winter air temperatures remained favorable for ice wedge growth throughout the Holocene, the timing of ice wedge formation reflects changes in snowfall. Overall, this study provides the first reconstruction of ice wedge formation from a high Arctic polar desert environment.

scholarly journals Hydrological controls on DOC : nitrate resource stoichiometry in a lowland, agricultural catchment, southern UK

2017 ◽  
Author(s):  
Catherine M. Heppell ◽  
Andrew Binley ◽  
Mark Trimmer ◽  
Tegan Darch ◽  
Ashley Jones ◽  
...  
Keyword(s):  
Climate Change ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
River Water ◽  
Positive Relationship ◽  
Agricultural Landscapes ◽  
Lowland River ◽  
Significant Positive Relationship ◽  
Molar Ratios ◽  
The Relationship

Abstract. The role that hydrology plays in governing the interactions between dissolved organic carbon (DOC) and nitrogen in rivers draining lowland, agricultural landscapes is currently poorly understood, yet important to assess given the potential changes to production and delivery of DOC and nitrate arising from climate change. We measured DOC and nitrate concentrations in river water of six reaches of the lowland River Hampshire Avon (Wiltshire, southern UK) in order to quantify the relationship between Baseflow Index (BFI) and DOC : nitrate molar ratios across contrasting geologies (Chalk, Greensand and clay). We found a significant positive relationship between nitrate and Baseflow Index (p 

scholarly journals Dissolved organic carbon loss from Yedoma permafrost amplified by ice wedge thaw

2013 ◽  
Vol 8 (3) ◽  
pp. 035023 ◽  
Author(s):  
J E Vonk ◽  
P J Mann ◽  
K L Dowdy ◽  
A Davydova ◽  
S P Davydov ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Carbon Loss ◽  
Ice Wedge

Recent changes in climate and permafrost temperatures at forested and polar desert sites in northern Canada1This article is one of a series of papers published in this CJES Special Issue on the theme of Fundamental and applied research on permafrost in Canada.

2012 ◽  
Vol 49 (8) ◽  
pp. 914-924 ◽  
Author(s):  
Sharon L. Smith ◽  
Jennifer Throop ◽  
Antoni G. Lewkowicz
Keyword(s):  
Climate Warming ◽  
Thermal Response ◽  
High Arctic ◽  
Ground Temperature ◽  
Data Sets ◽  
Polar Desert ◽  
Air Temperatures ◽  
Recent Climate ◽  
Temperature Records ◽  
The 1960S

Climate and ground temperature records up to 30 years in length from permafrost monitoring sites in a polar desert at Alert, Nunavut, and a boreal forest at Table Mountain, Northwest Territories, were analyzed by season and year to assess the ground thermal response to recent climate warming. Methods were developed to standardize incomplete ground temperature data sets and to hindcast air temperatures for comparative analysis. The timing and magnitude of climate warming varied, beginning in the 1960s in the Mackenzie Valley and the 1970s in the High Arctic. Ground temperature increases occurred in both regions but varied in magnitude and timing in relation to the external forcing and permafrost conditions. Significant increases in winter air temperatures in both regions appear to be largely responsible for recent increases in ground temperature, particularly at the polar desert sites where snow cover is minimal.

Water chemistry and dissolved organic carbon trends in lakes from Canada’s Atlantic Provinces: no recovery from acidification measured after 25 years of lake monitoring

2011 ◽  
Vol 68 (4) ◽  
pp. 663-674 ◽  
Author(s):  
Thomas A. Clair ◽  
Ian F. Dennis ◽  
Robert Vet
Keyword(s):  
North America ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Acid Deposition ◽  
Base Cations ◽  
Sampling Period ◽  
Lake Chemistry ◽  
Neutralization Capacity ◽  
Air Temperatures ◽  
Recovery From Acidification

We analyzed chemistry trends for 66 Atlantic Canada lakes using data collected from 1983 to 2007, as well as from 1990 to 2007 and 2000 to 2007 for the original 66 and a further 25 lakes that were later added to the network. Though receiving the lowest acid deposition in eastern North America, the region’s waters are seriously affected by acid rain because of poorly buffering soils and bedrock. Earlier work had shown that despite large decreases in sulfate deposition, lake pH and calculated acid neutralization capacity (ANCc) had not increased as they had elsewhere in North America and Europe. Despite a 50% decrease in acid deposition, a further 10 years of lake chemistry data showed a regional increase in ANCc only at the beginning of the sampling period but no increase since the early 1990s. There were also no increases in pH and base cations in the region’s lakes. We show a regional increase in Gran titration ANC (ANCG) from 2000 to the present, which we ascribe to increases in dissolved organic carbon that is probably due to a regional increase in annual air temperatures.

Spiking regional vis-NIR calibration models with local samples to predict soil organic carbon in two High Arctic polar deserts using a vis-NIR probe

2015 ◽  
Vol 95 (3) ◽  
pp. 237-249 ◽  
Author(s):  
Amanda L. Guy ◽  
Steven D. Siciliano ◽  
Eric G. Lamb
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
High Arctic ◽  
Calibration Model ◽  
Regional Models ◽  
Desert Soils ◽  
Polar Desert ◽  
Calibration Models ◽  
Target Sites

Guy, A. L., Siciliano, S. D. and Lamb, E. G. 2015. Spiking regional vis-NIR calibration models with local samples to predict soil organic carbon in two High Arctic polar deserts using a vis-NIR probe. Can. J. Soil Sci. 95: 237–249. In situ visible and near-infrared (vis-NIR) spectroscopy is a potential solution to the logistic constraints limiting the accuracy and spatial resolution of soil organic carbon (SOC) estimates for Arctic regions. The objective of our study was to develop a calibration model based on field-condition soils for in situ applications to predict SOC in High Arctic polar desert soils from vis-NIR spectra. Soils (n=240) for calibration models were collected from three regional Canadian Arctic sites in 2010 and two local target sites in 2013. Local and regional calibration models were developed using partial least squares regression (PLSR). We assessed whether spiking or spiking and extra-weighting, regional models with calibration samples from local sites improved prediction of the local sites. The local model yielded successful prediction of target sites (R2=0.91) whereas unspiked regional models had poor prediction accuracy (R2=0.07 to 0.36; n=4). Spiking regional models with as few as 12 local samples greatly improved the SOC prediction of target sites; the best spiked models had R2 between 0.69 and 0.86. Extra-weighting spiking subsets in regional models yielded limited improvements in prediction performance. These results suggest that regional vis-NIR calibration models can be successfully used to predict SOC in High Arctic polar desert soils. The in situ application of these calibration models using field-portable instruments in remote areas, relative to traditional laboratory methods, can achieve higher sample sizes and the ability to characterize the spatial variability of SOC.

scholarly journals Dissolved Organic Carbon Chemostasis in Antarctic Polar Desert Streams

2021 ◽  
Author(s):  
Christa L. Torrens ◽  
Michael N. Gooseff ◽  
Diane M. McKnight
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Polar Desert ◽  
Desert Streams

scholarly journals A Model of Ice Wedge Polygon Drainage in Changing Arctic Terrain

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3376
Author(s):  
Vitaly A. Zlotnik ◽  
Dylan R. Harp ◽  
Elchin E. Jafarov ◽  
Charles J. Abolt
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Active Layer ◽  
Edge Effect ◽  
The Arctic ◽  
Field Observations ◽  
Advective Transport ◽  
Cross Sectional ◽  
Flow Paths ◽  
Ice Wedge

As ice wedge degradation and the inundation of polygonal troughs become increasingly common processes across the Arctic, lateral export of water from polygonal soils may represent an important mechanism for the mobilization of dissolved organic carbon and other solutes. However, drainage from ice wedge polygons is poorly understood. We constructed a model which uses cross-sectional flow nets to define flow paths of meltwater through the active layer of an inundated low-centered polygon towards the trough. The model includes the effects of evaporation and simulates the depletion of ponded water in the polygon center during the thaw season. In most simulations, we discovered a strong hydrodynamic edge effect: only a small fraction of the polygon volume near the rim area is flushed by the drainage at relatively high velocities, suggesting that nearly all advective transport of solutes, heat, and soil particles is confined to this zone. Estimates of characteristic drainage times from the polygon center are consistent with published field observations.

scholarly journals Sustainability of High Arctic Ponds in a Polar Desert Environment

ARCTIC ◽  
2010 ◽  
Vol 63 (1) ◽  
Author(s):  
Anna Abnizova ◽  
Kathy L. Young
Keyword(s):  
High Arctic ◽  
Desert Environment ◽  
Polar Desert ◽  
Arctic Ponds
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