scholarly journals The influence of river discharge on the thawing of sea ice, Mackenzie River Delta: albedo and temperature analyses

1994 ◽  
Vol 13 (1) ◽  
pp. 83-94 ◽  
Author(s):  
K. G. Dean ◽  
W. J. Stringer ◽  
K. Ahlnäs ◽  
C. Searcy ◽  
T. Weingartner
Keyword(s):  
Sea Ice ◽  
River Discharge ◽  
River Delta ◽  
Mackenzie River

The influence of river discharge on the thawing of sea ice, Mackenzie River Delta: albedo and temperature analyses

1994 ◽  
Vol 13 (1) ◽  
pp. 83-94 ◽  
Author(s):  
K. G. DEAN ◽  
W. J. STRINGER ◽  
K. AHLNAS ◽  
C. SEARCY ◽  
T. WEINGARTNER
Keyword(s):  
Sea Ice ◽  
River Discharge ◽  
River Delta ◽  
Mackenzie River

scholarly journals Modeling of the Beaufort ice-ocean climatology change

2001 ◽  
Vol 33 ◽  
pp. 560-566 ◽  
Author(s):  
Larissa Nazarenko ◽  
Nickolai Tausnev
Keyword(s):  
Sea Ice ◽  
Air Temperature ◽  
River Discharge ◽  
Surface Air Temperature ◽  
Beaufort Sea ◽  
Eddy Diffusion ◽  
Sensitivity Study ◽  
Ocean Model ◽  
Ocean Layer ◽  
Mackenzie River

AbstractA coupled ice-ocean model is used to study the sensitivity of the Beaufort Sea climatology to representation of sub-grid-scale eddies; to hypothetically not present and double Mackenzie River discharge; and to approximate climate warming specified through a surface air-temperature increase of 3° C. The eddy effect is considered in two ways: as eddy interaction with sea-floor topography yielding a driving force ("neptune" parameterization) and as eddy diffusion and viscosity. The model with neptune parameterization reproduces surface layer circulation, as well as the bathymetrically steered Beaufort Undercurrent, while the model with usual damping does not simulate the Beaufort Undercurrent. The absence of the strong boundary Beaufort Undercurrent affects the thermohaline structure of the Beaufort Sea which becomes less consistent with observational data. The increase of the Mackenzie River discharge causes more northward transport of sea ice, resulting in sea-ice thinning in Mackenzie Bay, while the absence of the Mackenzie River discharge induces southward sea-ice drift and sea-ice thickening in Mackenzie Bay. The sensitivity study of surface air-temperature warming shows a shrinkage of sea ice by 6% in area and 15% in volume, causing the freshening and warming of the surface ocean layer. The sensitivity studies of river discharge and surface air temperature use the neptune parameterization.

A river-coastal sea ice interaction model: Mackenzie River Delta

1996 ◽  
Vol 101 (C4) ◽  
pp. 8885-8894 ◽  
Author(s):  
Craig Searcy ◽  
Kenneson Dean ◽  
William Stringer
Keyword(s):  
Sea Ice ◽  
Interaction Model ◽  
River Delta ◽  
Coastal Sea ◽  
Mackenzie River

scholarly journals Effects of Mackenzie River discharge and bathymetry on sea ice in the Beaufort Sea

2014 ◽  
Vol 41 (3) ◽  
pp. 873-879 ◽  
Author(s):  
S. V. Nghiem ◽  
D. K. Hall ◽  
I. G. Rigor ◽  
P. Li ◽  
G. Neumann
Keyword(s):  
Sea Ice ◽  
River Discharge ◽  
Beaufort Sea ◽  
Mackenzie River

scholarly journals Cryospheric Impacts of Soviet River Diversion Schemes

1984 ◽  
Vol 5 ◽  
pp. 61-68 ◽  
Author(s):  
T. Holt ◽  
P. M. Kelly ◽  
B. S. G. Cherry
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
River Discharge ◽  
Large Scale ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Sea Ice Concentration ◽  
Ice Concentration ◽  
The Arctic Ocean ◽  
The Impact

Soviet plans to divert water from rivers flowing into the Arctic Ocean have led to research into the impact of a reduction in discharge on Arctic sea ice. We consider the mechanisms by which discharge reductions might affect sea-ice cover and then test various hypotheses related to these mechanisms. We find several large areas over which sea-ice concentration correlates significantly with variations in river discharge, supporting two particular hypotheses. The first hypothesis concerns the area where the initial impacts are likely to which is the Kara Sea. Reduced riverflow is associated occur, with decreased sea-ice concentration in October, at the time of ice formation. This is believed to be the result of decreased freshening of the surface layer. The second hypothesis concerns possible effects on the large-scale current system of the Arctic Ocean and, in particular, on the inflow of Atlantic and Pacific water. These effects occur as a result of changes in the strength of northward-flowing gradient currents associated with variations in river discharge. Although it is still not certain that substantial transfers of riverflow will take place, it is concluded that the possibility of significant cryospheric effects and, hence, large-scale climate impact should not be neglected.

Mercury in the Mackenzie River delta and estuary: Concentrations and fluxes during open-water conditions

2009 ◽  
Vol 407 (8) ◽  
pp. 2980-2988 ◽  
Author(s):  
Jennifer A. Graydon ◽  
Craig A. Emmerton ◽  
Lance F.W. Lesack ◽  
Erin N. Kelly
Keyword(s):  
Open Water ◽  
River Delta ◽  
Water Conditions ◽  
Mackenzie River

scholarly journals Morphological and ecological variation among populations and subspecies of Burbot (Lota lota [L, 1758]) from the Mackenzie River Delta, Canada

2015 ◽  
Vol 128 (4) ◽  
pp. 377 ◽  
Author(s):  
Hans Recknagel ◽  
Amy Amos ◽  
Kathryn R. Elmer
Keyword(s):  
River Delta ◽  
Pungitius Pungitius ◽  
Local Conditions ◽  
Lota Lota ◽  
Phenotypic Differences ◽  
Carbon And Nitrogen ◽  
Stable Isotope Signatures ◽  
Morphological Differences ◽  
Eastern Edge ◽  
Mackenzie River

The Burbot (Lota lota [L, 1758]) is a holarctic distributed freshwater fish in the Gadidae family. In northwestern Canada, it has an important value for local and traditional fisheries. We describe the morphology and ecology of Burbot from four populations in the Mackenzie River Delta. Two subspecies come into contact in this area, which is the western edge of Lota lota maculosa distribution (one population in our study) and the eastern edge of Lota lota lota distribution (three populations in our study). We found the combined length–weight relationship in these four populations to be log10 (weight) = −3.986 + 2.617 * log10 (length). There was no difference in mean body length (overall mean and standard deviation 73.4 ± 8.7 cm), although the L. l. lota populations were heavier than the L. l. maculosa population. All populations differed in their carbon and nitrogen stable isotope signatures (δ15N overall mean 12.1 ± 1.59; δ13C overall mean −25.54 ± 1.11). Main prey items were four fish species: Ninespine Stickleback (Pungitius pungitius [L, 1758]), Broad Whitefish (Coregonus nasus [Pallas, 1776]), Burbot, and Northern Pike (Esox lucius [L, 1758]). Ecological and morphological differences may be due to local conditions and population variability or to the different Lota lota subspecies. More ecological and morphological information from this region is needed to resolve possible phenotypic differences between the subspecies.

Studying Fluvial Tipping Points with Remotely Sensed Observations and Hydroclimatic Data in the Selenga River Delta

2020 ◽  
Author(s):  
Saeid Aminjafari ◽  
Ian Brown ◽  
Jerker Jarsjö ◽  
Sergey R. Chalov ◽  
Fernando Jaramillo
Keyword(s):  
Lake Baikal ◽  
River Discharge ◽  
Climatic Conditions ◽  
Flow Path ◽  
River Delta ◽  
Tipping Points ◽  
Runoff Water ◽  
Selenga River ◽  
Selenga River Delta ◽  
Hydrological Changes

<p>Lake Baikal, located in eastern Russia, is the oldest (25 million years) and the deepest (~1800 meters) lake in the world. There are many rivers flowing into the Lake Baikal (~ 365 rivers), of which the Selenga River is the most important one being responsible for almost 55% of the runoff water into the system and also 60% of the transported sediments. As the hydrological changes of the river and its delta enormously alter the neighbouring area, it is of utmost importance to explore the dynamics of change in terms of flow magnitude, paths and fluvial geomorphology, and the related tipping points defining different states. The questions this study aims to answer are: What are the fluvial geomorphological and hydrological changes? What fluvial geomorphological tipping points can be identified during the last 34 years and what are the discharge and climatic conditions that induce them? In this study, we use the Global Surface Water Dataset (GSWD) to analyze the changes in the river’s stream network. With these products, we assess changes in several fluvial geomorphological proxies (e.g., sinuosity, fractal dimension, meandering characteristics, planform information) and identify possible tipping points. We relate these changes to different hydrological and climatic conditions such as precipitation, river discharge and Lake Baikal water level. We find evident changes in the meandering behaviour and flow path of the Selenga River tributaries in the Delta. The number of oxbow lakes based and corresponding size distribution has varied in time, and evident flow path changes occur that seem to be related to flooding periods, and there appears to be a consistent relationship between meandering and the river discharge variability. These results enable policymakers to understand different contributing factors altering the Selenga River Delta and ultimately leading to better decisions to manage the effects of these changes in the area.</p>

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