Utilizing chromophoric dissolved organic matter measurements to derive export and reactivity of dissolved organic carbon exported to the Arctic Ocean: A case study of the Yukon River, Alaska

2009 ◽  
Vol 36 (6) ◽  
Author(s):  
Robert G. M. Spencer ◽  
George R. Aiken ◽  
Kenna D. Butler ◽  
Mark M. Dornblaser ◽  
Robert G. Striegl ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Dissolved Organic Matter ◽  
Dissolved Organic Carbon ◽  
Arctic Ocean ◽  
The Arctic ◽  
Chromophoric Dissolved Organic Matter ◽  
Yukon River ◽  
The Arctic Ocean

Evaluating Dissolved Organic Carbon Retrieval in the Lena River Delta using Sentinel 3 OLCI Data

2021 ◽  
Author(s):  
Rene Preusker ◽  
Jan El Kassar ◽  
Bennet Juhls
Keyword(s):  
Remote Sensing ◽  
Organic Matter ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Arctic Ocean ◽  
The Arctic ◽  
Lena River ◽  
The Arctic Ocean ◽  
Arctic Rivers

<p>As air temperatures in the Arctic continue to rise, permafrost thaw intensifies, and discharge from the Arctic rivers increases. These drastic changes are likely to accelerate mobilization of organic matter and its export through rivers into the Arctic Ocean. Therefore, thorough monitoring of these processes becomes increasingly important. The Lena River with its large catchment area is one of the major sources of the organic carbon in the Arctic Ocean and, therefore, plays a crucial role in the Arctic carbon cycle. <br>To observe current and future changes of carbon transport via the Lena River, a new monitoring program has been initiated in 2018. In situ water samples are collected from the one of the Lena Delta branches every several days. Since generally the in situ sampling in the Arctic is challenging and costly, in this study, we test the potential of remote sensing to complement the field observations. Remote sensing provides synoptic spatial coverages and high temporal resolution at high latitudes. <br>We test the retrieval of dissolved organic carbon (DOC) from satellite-derived chromophoric dissolved organic matter (CDOM). For this, we use measurements of the Ocean & Land Colour Instrument (OLCI) on board the Sentinel-3 satellites in combination with beforehand tested atmospheric correction algorithms and CDOM retrieval algorithms. The quality of the satellite retrieved DOC of the Lena River water is assessed by DOC, measured in the in situ samples. Remotely sensed DOC contributes to an improvement of DOC fluxes monitoring, which can potentially be extended to all big Arctic rivers.</p>

Seasonality in Lena River biogeochemistry and dissolved organic matter

2020 ◽  
Author(s):  
Bennet Juhls ◽  
Pier Paul Overduin ◽  
Colin Andrew Stedmon ◽  
Anne Morgenstern ◽  
Hanno Meyer ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Arctic Ocean ◽  
The Arctic ◽  
Research Station ◽  
Lena River ◽  
Continuous Sampling ◽  
The Arctic Ocean ◽  
Frequency Sampling ◽  
Sampling Program

<p>The carbon export by rivers to the Arctic Ocean is expected to increase in response to the rapidly changing climate in the Arctic (Camill, 2005; Freeman et al., 2001; Frey and Smith, 2005). This is in part due to thawing permafrost and mobilization of particulate and dissolved organic matter (DOM). The Lena River delivers approximately one fifth of the total river discharge to the Arctic Ocean and is the main source of DOM in the Laptev Sea shelf (Thibodeau et al., 2014). To date river fluxes of DOM have been based on sparse coverage of sample across the hydrograph about 700 km upstream (Cooper et al 2005; Raymond et al 2007; Stedmon et al 2011; Amon et al 2012). The effects of low frequency sampling on load estimates are unknown and potentially large for systems such as these where there are considerable changes across the hydrograph.   Here we present results from a unique high frequency sampling program and evaluate its viability to monitor export fluxes of DOM and its biogeochemistry in the Lena River. The sampling takes place close to the river mouth at the research station Samoylov in the central Lena River Delta. The Samoylov research station allows a unique chance for continuous sampling since it operates throughout the year. The sampling program includes measurements of several water parameters, such as temperature, electric conductivity, dissolved organic carbon (DOC), spectral CDOM absorption (aCDOM), fluorescent dissolved organic matter (FDOM) and water stable isotopes.<br>The data facilitated the identification of the main drivers behind the seasonality of DOM concentration and biogeochemistry of the Lena River. Three main water sources could be identified (1) (snow) melt water, (2) rain water and (3) subsurface water. Melt and rain water are found to be the prevailing water sources that combined transport 5.8 Tg C dissolved organic matter (~ 85 % of annual flux (6.8 Tg C)) into the Lena River. The high number of samples throughout the whole year allowed flux calculations that are independently from load models that likely lead to a large variation of earlier studies.<br>The absorption properties of DOM revealed changing composition and sources of DOM throughout the year. Decreasing SUVA values during the summer point towards an increasing fraction of old DOM which potentially originates from degrading permafrost. In contrast, during the spring freshet, high SUVA indicate mostly fresh organic matter with high molecular weight and high aromaticity.<br>This dataset represents the first year of a planned long-term monitoring program at the Research Station Samoylov Island and provides a baseline data set against which future change of this large integrative system may be measured. A continuous sampling of Arctic River water will facilitate to identify intra and inter-annual trends with ongoing climate change.</p>

scholarly journals Eroding permafrost coasts release low amounts of dissolved organic carbon (DOC) from ground ice into the nearshore zone of the Arctic Ocean

2016 ◽  
Vol 30 (7) ◽  
pp. 1054-1068 ◽  
Author(s):  
George Tanski ◽  
Nicole Couture ◽  
Hugues Lantuit ◽  
Antje Eulenburg ◽  
Michael Fritz
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Arctic Ocean ◽  
The Arctic ◽  
Nearshore Zone ◽  
Ground Ice ◽  
The Arctic Ocean

scholarly journals Linkages among runoff, dissolved organic carbon, and the stable oxygen isotope composition of seawater and other water mass indicators in the Arctic Ocean

2005 ◽  
Vol 110 (G2) ◽  
pp. n/a-n/a ◽  
Author(s):  
Lee W. Cooper ◽  
Ronald Benner ◽  
James W. McClelland ◽  
Bruce J. Peterson ◽  
Robert M. Holmes ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Arctic Ocean ◽  
Oxygen Isotope ◽  
Water Mass ◽  
Isotope Composition ◽  
The Arctic ◽  
Stable Oxygen Isotope ◽  
The Arctic Ocean ◽  
Stable Oxygen
Sign in / Sign up

Export Citation Format

Share Document