scholarly journals Understanding of Cyclic Volatile Methyl Siloxane Fate in a High Latitude Lake Is Constrained by Uncertainty in Organic Carbon–Water Partitioning

2016 ◽  
Vol 51 (1) ◽  
pp. 401-409 ◽  
Author(s):  
Ingjerd Sunde Krogseth ◽  
Michael John Whelan ◽  
Guttorm Normann Christensen ◽  
Knut Breivik ◽  
Anita Evenset ◽  
...  
Keyword(s):  
Organic Carbon ◽  
High Latitude ◽  
Water Partitioning

scholarly journals Finding the VOICE: organic carbon isotope chemostratigraphy of Late Jurassic – Early Cretaceous Arctic Canada

2019 ◽  
Vol 157 (10) ◽  
pp. 1643-1657 ◽  
Author(s):  
Jennifer M. Galloway ◽  
Madeleine L. Vickers ◽  
Gregory D. Price ◽  
Terence Poulton ◽  
Stephen E. Grasby ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Carbon Isotope ◽  
High Latitude ◽  
Large Scale ◽  
The Arctic ◽  
Sudden Increase ◽  
Arctic Canada ◽  
Contributing Factors ◽  
Compositional Evolution ◽  
Sverdrup Basin

AbstractA new carbon isotope record for two high-latitude sedimentary successions that span the Jurassic–Cretaceous boundary interval in the Sverdrup Basin of Arctic Canada is presented. This study, combined with other published Arctic data, shows a large negative isotopic excursion of organic carbon (δ13Corg) of 4‰ (V-PDB) and to a minimum of −30.7‰ in the probable middle Volgian Stage. This is followed by a return to less negative values of c. −27‰. A smaller positive excursion in the Valanginian Stage of c. 2‰, reaching maximum values of −24.6‰, is related to the Weissert Event. The Volgian isotopic trends are consistent with other high-latitude records but do not appear in δ13Ccarb records of Tethyan Tithonian strata. In the absence of any obvious definitive cause for the depleted δ13Corg anomaly, we suggest several possible contributing factors. The Sverdrup Basin and other Arctic areas may have experienced compositional evolution away from open-marine δ13C values during the Volgian Age due to low global or large-scale regional sea levels, and later become effectively coupled to global oceans by Valanginian time when sea level rose. A geologically sudden increase in volcanism may have caused the large negative δ13Corg values seen in the Arctic Volgian records but the lack of precise geochronological age control for the Jurassic–Cretaceous boundary precludes direct comparison with potentially coincident events, such as the Shatsky Rise. This study offers improved correlation constraints and a refined C-isotope curve for the Boreal region throughout latest Jurassic and earliest Cretaceous time.

Snowmelt dominance of dissolved organic carbon in high-latitude watersheds: Implications for characterization and flux of river DOC

2006 ◽  
Vol 33 (10) ◽  
pp. n/a-n/a ◽  
Author(s):  
Jacques Finlay ◽  
Jason Neff ◽  
Sergei Zimov ◽  
Anna Davydova ◽  
Sergei Davydov
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
High Latitude

scholarly journals Precipitation-induced transport and phase partitioning of organophosphate esters (OPEs) in urban and rural watersheds

2021 ◽  
Author(s):  
Boluwatife Awonaike ◽  
Ying Duan Lei ◽  
Frank Wania
Keyword(s):  
Organic Carbon ◽  
Field Data ◽  
Organophosphate Esters ◽  
Phase Partitioning ◽  
Water Partitioning ◽  
Predicted Values

Particle-bound OPEs were observed at fractions higher than expected based on predicted partitioning behaviour, i.e. organic carbon–water partitioning ratios (log ) calculated from field data were generally higher than predicted values.

scholarly journals ORCHIDEE MICT-LEAK (r5459), a global model for the production, transport, and transformation of dissolved organic carbon from Arctic permafrost regions – Part 1: Rationale, model description, and simulation protocol

2019 ◽  
Vol 12 (8) ◽  
pp. 3503-3521 ◽  
Author(s):  
Simon P. K. Bowring ◽  
Ronny Lauerwald ◽  
Bertrand Guenet ◽  
Dan Zhu ◽  
Matthieu Guimberteau ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
High Latitude ◽  
Land Surface ◽  
River Network ◽  
Model Description ◽  
Surface Model ◽  
System Modelling ◽  
Earth System ◽  
Simulation Protocol

Abstract. Few Earth system models adequately represent the unique permafrost soil biogeochemistry and its respective processes; this significantly contributes to uncertainty in estimating their responses, and that of the planet at large, to warming. Likewise, the riverine component of what is known as the “boundless carbon cycle” is seldom recognised in Earth system modelling. The hydrological mobilisation of organic material from a ∼1330–1580 PgC carbon stock to the river network results in either sedimentary settling or atmospheric “evasion”, processes widely expected to increase with amplified Arctic climate warming. Here, the production, transport, and atmospheric release of dissolved organic carbon (DOC) from high-latitude permafrost soils into inland waters and the ocean are explicitly represented for the first time in the land surface component (ORCHIDEE) of a CMIP6 global climate model (Institut Pierre Simon Laplace – IPSL). The model, ORCHIDEE MICT-LEAK, which represents the merger of previously described ORCHIDEE versions MICT and LEAK, mechanistically represents (a) vegetation and soil physical processes for high-latitude snow, ice, and soil phenomena and (b) the cycling of DOC and CO2, including atmospheric evasion, along the terrestrial–aquatic continuum from soils through the river network to the coast at 0.5 to 2∘ resolution. This paper, the first in a two-part study, presents the rationale for including these processes in a high-latitude-specific land surface model, then describes the model with a focus on novel process implementations, followed by a summary of the model configuration and simulation protocol. The results of these simulation runs, conducted for the Lena River basin, are evaluated against observational data in the second part of this study.

Late Jurassic – earliest Cretaceous prolonged shelf dysoxic–anoxic event and its possible causes

2020 ◽  
Vol 157 (10) ◽  
pp. 1622-1642
Author(s):  
MA Rogov ◽  
EV Shchepetova ◽  
VA Zakharov
Keyword(s):  
Organic Carbon ◽  
Black Shale ◽  
High Latitude ◽  
Late Jurassic ◽  
Black Shales ◽  
Time Interval ◽  
Oceanic Circulation ◽  
Anoxic Event ◽  
Anoxic Events

AbstractThe Late Jurassic – earliest Cretaceous time interval was characterized by a widespread distribution of dysoxiс–anoxiс environments in temperate- and high-latitude epicontinental seas, which could be defined as a shelf dysoxic–anoxic event (SDAE). In contrast to black shales related to oceanic anoxic events, deposits generated by the SDAE were especially common in shelf sites in the Northern Hemisphere. The onset and termination of the SDAE was strongly diachronous across different regions. The SDAE was not associated with significant disturbances of the carbon cycle. Deposition of organic-carbon-rich sediment and the existence of dysoxic–anoxic conditions during the SDAE lasted up to c. 20 Ma, but this event did not cause any remarkable biotic extinction. Temperate- and high-latitude black shale occurrences across the Jurassic–Cretaceous boundary have been reviewed. Two patterns of black shale deposition during the SDAE are recognized: (1) Subboreal type, with numerous thin black shale beds, bounded by sediments with very low total organic carbon (TOC) values; and (2) Boreal type, distinguished by predominantly thick black shale successions showing high TOC values and prolonged anoxic–dysoxic conditions. These types appear to be unrelated to differences in accommodation space, and can be clearly recognized irrespective of the thickness of shale-bearing units. Black shales in high-latitude areas in the Southern Hemisphere strongly resemble Boreal types of black shale by their mode of occurrence. The causes of this SDAE are linked to long-term warming and changes in oceanic circulation. Additionally, the long-term disturbance of planktonic communities may have triggered overall increased productivity in anoxia-prone environments.

scholarly journals Vulnerability of high-latitude soil organic carbon in North America to disturbance

2011 ◽  
Vol 116 ◽  
Author(s):  
Guido Grosse ◽  
Jennifer Harden ◽  
Merritt Turetsky ◽  
A. David McGuire ◽  
Philip Camill ◽  
...  
Keyword(s):  
North America ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
High Latitude
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