Ice-Push Ramparts in the George River Basin, Labrador-Ungava

ARCTIC ◽  
1965 ◽  
Vol 18 (3) ◽  
pp. 189 ◽  
Author(s):  
James A. Peterson
Keyword(s):  
River Basin ◽  
Open Water ◽  
Field Work ◽  
Baffin Island ◽  
Lake Area ◽  
Proglacial Lakes ◽  
George River

Reports field work on ice-push ramparts in the Whitegull Lake area of Quebec Province (55 30 N, 64 15 W). Modes of formation of ramparts during the partial open water season are reviewed and examples illus. Raised shorelines described by Low (No 10377) are re-interpreted as possible ice-push ramparts. Comparison of the Labrador Peninsula lakes with proglacial lakes in Baffin Island may assist interpretation of these features.

ANALYSIS OF 10BE-BASED EROSION AND DENUDATION RATES IN THE GEORGE RIVER BASIN, TASMANIA, AUSTRALIA

2019 ◽  
Author(s):  
Leah A. VanLandingham ◽  
◽  
Eric W. Portenga ◽  
Paul R. Bierman ◽  
Ted Lefroy
Keyword(s):  
River Basin ◽  
Denudation Rates ◽  
George River

scholarly journals Assessing Climate Change Trends and Their Relationships with Alpine Vegetation and Surface Water Dynamics in the Everest Region, Nepal

Atmosphere ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 987
Author(s):  
Mana Raj Rai ◽  
Amnat Chidthaisong ◽  
Chaiwat Ekkawatpanit ◽  
Pariwate Varnakovida
Keyword(s):  
Climate Change ◽  
Surface Water ◽  
River Basin ◽  
Climate Impacts ◽  
Glacial Lake ◽  
Annual Precipitation ◽  
Series Data ◽  
Lake Area ◽  
Alpine Vegetation ◽  
Koshi River Basin

The Himalayas, especially the Everest region, are highly sensitive to climate change. Although there are research works on this region related to cryospheric work, the ecological understandings of the alpine zone and climate impacts are limited. This study aimed to assess the changes in surface water including glacier lake and streamflow and the spatial and temporal changes in alpine vegetation and examine their relationships with climatic factors (temperature and precipitation) during 1995–2019 in the Everest region and the Dudh Koshi river basin. In this study, Landsat time-series data, European Commission’s Joint Research Center (JRC) surface water data, ECMWF Reanalysis 5th Generation (ERA5) reanalysis temperature data, and meteorological station data were used. It was found that the glacial lake area and volume are expanding at the rates of 0.0676 and 0.0198 km3/year, respectively; the average annual streamflow is decreasing at the rate of 2.73 m3/s/year. Similarly, the alpine vegetation greening as indicated by normalized difference vegetation index (NDVI) is increasing at the rate of 0.00352 units/year. On the other hand, the annual mean temperature shows an increasing trend of 0.0329 °C/year, and the annual precipitation also shows a significant negative monotonic trend. It was also found that annual NDVI is significantly correlated with annual temperature. Likewise, the glacial lake area expansion is strongly correlated with annual minimum temperature and annual precipitation. Overall, we found a significant alteration in the alpine ecosystem of the Everest region that could impact on the water–energy–food nexus of the Dudh Koshi river basin.

scholarly journals Fish, Machado River basin, Cacoal urban area, state of Rondônia, Brazil

Check List ◽  
2007 ◽  
Vol 3 (2) ◽  
pp. 94 ◽  
Author(s):  
Leane Perin ◽  
Oscar Akio Shibatta ◽  
Paulo Sérgio Bernarde
Keyword(s):  
Urban Area ◽  
River Basin ◽  
Urban Areas ◽  
Field Work ◽  
Gill Nets

The Pirarara and Tamarupa rivers are two urban tributaries of the Machado River in Cacoal municipality, state of Rondônia (RO), Brazil. Here we report a list of species of fishes from urban areas of Cacoal, being the first ichthyological study in this region. Field work at Cacoal was carried out from November 2004 until July 2005, using gill nets, casting nets, and long lines. Two hundred and twenty-two specimens were collected, and are distributed in 48 species, 14 families and 4 orders. The most representative order was Characiformes, with seven families and 23 species, followed by Siluriformes, with three families and 20 species.

Canadian field work in Baffin Island, 1964 and 1965

Polar Record ◽  
1966 ◽  
Vol 13 (83) ◽  
pp. 194-197 ◽  
Author(s):  
O. H. Løken
Keyword(s):  
Field Work ◽  
Baffin Island

scholarly journals Estimating Dynamics of Terminal Lakes in the Second Largest Endorheic River Basin of Northwestern China from 2000 to 2017 with Landsat Imagery

2019 ◽  
Vol 11 (10) ◽  
pp. 1164
Author(s):  
Bei Li ◽  
Yi-Chi Zhang ◽  
Ping Wang ◽  
Chao-Yang Du ◽  
Jing-Jie Yu
Keyword(s):  
River Basin ◽  
Water Consumption ◽  
Landsat Imagery ◽  
Water Diversion ◽  
Heihe River ◽  
Arid Environments ◽  
Lake Area ◽  
Landsat Images ◽  
East River ◽  
Terminal Lakes

Quantifying terminal-lake dynamics is crucial for understanding water-ecosystem-economy relationship across endorheic river basins in arid environments. In this study, the spatio-temporal variations in terminal lakes of the lower Heihe River Basin were investigated for the first time since the Ecological Water Diversion Project commenced in 2000. The lake area and corresponding water consumption were determined with 248 Landsat images. Vital recovery of lakes occurred two years after the implementation of the project, and the total lake area increased by 382.6%, from 30.7 to 148.2 km2, during 2002–2017. East Juyan Lake (EJL) was first restored as a project target and subsequently reached a maximum area of 70.1 km2. Water dispersion was initiated in 2003, with the East river prioritized for restoration. Swan Lake in the East river enlarged to 67.7 km2 by 2017, while the other four lakes temporarily existed or maintained an area < 7 km2, such as West Juyan Lake. Water consumed by lakes increased synchronously with lake area. The average water consumption of the six lakes was 1.03 × 108 m3/year, with 63% from EJL. The increasing terminal lakes; however, highlight the seasonal competition for water use between riparian vegetation and lake ecosystems in water-limited areas.

Assessing the Impacts of Temperature, Precipitation and Land Use Change on Open Water Bodies of Middle Ghaghara River Basin

2019 ◽  
pp. 185-202
Author(s):  
Rajesh Kumar ◽  
Prem Chandra Pandey ◽  
Pyarimohan Maharana ◽  
Hemant Gautam ◽  
Vijendra Kumar Pandey
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
River Basin ◽  
Open Water ◽  
Water Bodies

Greening dynamics and shrubland extent from remote sensing data using NDVI and NARI Indices: case study of the George River basin (Nunavik, Canada).

2020 ◽  
Author(s):  
Dr. Jean-Pierre Dedieu ◽  
Johann Housset ◽  
Arthur Bayle ◽  
Esther Lévesque ◽  
José Gérin-Lajoie
Keyword(s):  
Remote Sensing ◽  
River Basin ◽  
Vegetation Change ◽  
Vegetation Index ◽  
Spectral Band ◽  
Human Populations ◽  
Vegetation Types ◽  
Local Study ◽  
Basin Scale ◽  
George River

&lt;p&gt;Arctic greening trends are well documented at various scales (Fraser et al., 2011; Tremblay et al., 2012; Bjorkman et al., 2018). In this context, Remote Sensing offers a unique tool for estimating the high latitude vegetation evolution in the relatively long-term, i.e. the Landsat archive since the 80&amp;#8217;s. Spectral indices derived from visible and infra-red wavelengths provide relations that can be used to quantify vegetation dynamics, we will combine the well-used Normalized Difference Vegetation Index (NDVI) and the recent Normalized Anthocyanins Reflectance Index (Bayle et al., 2019), using red-edge spectral band (690 to 710 &amp;#181;m) from Sentinel-2, to better quantify vegetation change over 30 years.&lt;/p&gt;&lt;p&gt;The application area is located in Nunavik, northern Qu&amp;#233;bec (Canada), and concerns the George River catchment (565 km length, 41&amp;#160;700&amp;#160;km&amp;#178;). This large river basin covers vegetation from boreal forest (South) to arctic tundra (North). Local study sites stem from the Kangiqsualujjuaq village (Ungava Bay) to 300 km south, along the main river and its tributaries.&lt;/p&gt;&lt;p&gt;NDVI: surface reflectance Landsat bands were gathered for three years 1985, 2000 and 2015 (respectively Landsat missions 5, 7 and 8). For each period of interest, the best August cloud-free scenes were chosen and merged to create a cloud free mosaic covering the study area. NDVI bands were calculated and compared after cloud and water masking. NDVI trends were compared between the main vegetation types following the newly released &amp;#8220;Ecological mapping of the vegetation of northern Quebec&amp;#8221; (MRNFP, 2018). Centroid of polygons within the main vegetation types of the map were used to classify the NDVI results and assess changes per type. Results of NDVI time evolution revealed a clear greening trend at the river basin scale. Although greening was observed across the whole latitudinal gradient, the relative NDVI increase was stronger on the northern half of the study area, mostly covered with tundra and subarctic vegetation. Both shrublands and sparsely vegetated zones dominated by rocks had the greatest relative NDVI increase. This is likely caused by improved growth of established prostrate vegetation over the past 30 years in response to increasing temperatures trend.&lt;/p&gt;&lt;p&gt;NARI: greening trends in the Eastern Canadian Arctic have been partly attributed to increases in shrub cover (Myers-smith et al., 2011) and specifically to Betula glandulosa (e.g. Tremblay et al., 2012). Such land cover changes alter species competition (Shevtosa et al., 1997) and soil thermal regime (Domine et al., 2015; Paradis et al., 2016). Transformations in biotic and abiotic conditions reduce the fruit productivity of low stature shrubs of the Ericaceae family (Lussier 2017), which in turn is expected to impact animal (Prescott and Richard 2013) and human populations (L&amp;#233;vesque et al., 2013; Boulanger-Lapointe et al., 2019). An innovative method has been developed in the French Alps to detect the late-fall reddening of shrub leaves and map shrublands (Bayle et al., 2019). Quantifying NARI dynamics related to NDVI dynamics could allow to gain a better understanding of species composition change related to current landscape transformation.&lt;/p&gt;

James Buckland Mawdsley (1894-1964)

ARCTIC ◽  
1965 ◽  
Vol 18 (2) ◽  
pp. 146
Author(s):  
A.R. Byers
Keyword(s):  
Great Influence ◽  
Mineral Resources ◽  
Field Work ◽  
The United States ◽  
Geological Survey ◽  
The Arctic ◽  
Lake Area ◽  
Northern Canada ◽  
Geographical Society ◽  
The North

James Buckland Mawdsley, M.B.E., Ph.D., F.R.S.C., a Charter Associate of the Arctic Institute of North America, died very suddenly on 3 December 1964 at the age of 70. As Director of the Institute for Northern Studies, University of Saskatchewan, he played a major role in its organization and development and exerted a very great influence on research in northern Canada. He was born on 22 July 1894 near Siena, Italy, the son of British-American parents. In 1904 the Mawdsley family left Italy and settled in the village of Gainsborough, southeastern Saskatchewan. After receiving his public and high school training in Saskatchewan he entered McGill University in 1913. His career, like that of many of his contemporaries, was interrupted by the First World War. Twice wounded in France, first with the Princess Patricia Canadian Light Infantry and then as a pilot with the Royal Flying Corps, he was awarded the M.B.E. at the end of the war. In 1919 he returned to McGill and two years later graduated in Mining Engineering. He then went to Princeton University where he obtained his Doctor of Philosophy degree in Geology in 1924. That same year he joined the Geological Survey of Canada and for the next five years applied his scientific knowledge to the problems of the regional geology of northwestern Quebec. A new chapter in his life began in 1929 when he accepted the appointment of professor and head of the Department of Geology at the University of Saskatchewan, a position he held until he became Dean of Engineering in 1961 and also the Director of the Institute for Northern Studies. In 1963 he retired as Dean and was then able to devote all his time to the affairs of the Institute. In addition to his academic duties his professional activities included field work in northern Saskatchewan for the Geological Survey of Canada and the Saskatchewan Department of Mineral Resources, and private consulting assignments took him to other parts of northern Canada, to the United States and Great Britain. He was the author of 51 scientific papers and his honours were many. He was elected a Fellow of the Royal Society of Canada in 1933 and was chairman of Section IV for the year 1954-55. He was president of the Geological Association of Canada during 1955-56 and of the Canadian Institute of Mining and Metallurgy for 1961-62. In 1953 he was awarded the Institute's Barlow Memorial Medal in recognition of his paper entitled "Uraninite-bearing deposits, Charlebois Lake area, northeastern Saskatchewan". He was a Fellow and Director of the Royal Canadian Geographical Society, a Fellow of the Geological Society of America, a member of the Society of Economic Geologists, the Engineering Institute of Canada, and the Association of Professional Engineers of Saskatchewan. He had an eventful life, travelled widely, met and was a friend to many people. Such qualities as tact, kindliness, sincerity and respect for the thoughts of others enabled him to present his views without arousing undue antagonism, and to cooperate with others in reaching decisions. Recognized as an able administrator, scientist, and teacher, perhaps his greatest service will prove to be the influence he had on those who worked or studied under him. In them he not only instilled a feeling of scientific curiosity but also a keen interest and love of the North.

Human geographies of sea ice: freeze/thaw processes around Cape Dorset, Nunavut, Canada

Polar Record ◽  
2008 ◽  
Vol 44 (1) ◽  
pp. 51-76 ◽  
Author(s):  
Gita J. Laidler ◽  
Pootoogoo Elee
Keyword(s):  
Sea Ice ◽  
Regional Scale ◽  
Open Water ◽  
Current Strength ◽  
Ice Formation ◽  
Future Research ◽  
Baffin Island ◽  
Freeze Thaw ◽  
Ice Conditions ◽  
Inuit Knowledge

ABSTRACTSea ice has been, and continues to be, an integral component of life in the Inuit community of Cape Dorset, Nunavut. Located on an island of the same name off the southwestern coast of Baffin Island, the strong Hudson Strait currents prevent extensive ice formation around the community. Nevertheless, sea ice remains an important travel and hunting platform, enabling access to Baffin Island, hunting and fishing grounds, and nearby communities. With the combined importance, dynamism, and continuous use of this frozen ocean environment, local Inuit elders and hunters have developed a detailed and nuanced understanding of sea ice conditions, freeze/thaw processes, and the influences of winds and currents on ice conditions. Working collaboratively with the community of Cape Dorset since October, 2003, we present the results of 30 semi-directed interviews, 5 sea ice trips, and 2 focus groups to provide a baseline understanding of local freezing processes (near-shore, open water, sea ice thickening, landfast ice, floe edge, and tidal cracks), melting processes (snow melt, water accumulation and drainage, break-up, and cracks/leads), wind influences on sea ice (wind direction and strength affecting sea ice formation, and movement), and current influences on sea ice (tidal variations and current strength affecting sea ice formation, movement, and polynya size/location). Strong emphasis is placed on Inuktitut terminology and spatial delineations of localised ice conditions and features. Therefore, this paper provides insights into local scale ice conditions and dynamics around Cape Dorset that are not captured in regional scale studies of Hudson Bay and/or Hudson Strait. Results have the potential to inform future research efforts on local/regional sea ice monitoring, the relationship between Inuit knowledge, language, and the environment, and addressing community interests through targeted studies.

Physical and Chemical Characteristics of Ogac Lake, a Landlocked Fiord on Baffin Island

1967 ◽  
Vol 24 (5) ◽  
pp. 981-1015 ◽  
Author(s):  
Ian A. McLaren
Keyword(s):  
Heat Budget ◽  
Late Summer ◽  
Open Water ◽  
Baffin Island ◽  
Tidal Amplitude ◽  
Sea Temperature ◽  
Tidal Water ◽  
Anoxic Layer ◽  
Temperature Inversions ◽  
Physical And Chemical

Ogac Lake is the small (148 ha) landlocked head of a fiord with three distinct basins. It receives highest spring tides (maximal range 12 m, as high as 1.2 m above lake level) monthly during the open-water season through a narrow entrance. The predictable inflows displaced about one-quarter of the lake's volume in 1957. The lake is meromictic, fresh at the surface and 28‰ salinity at depth. Some 55 kg/m2 salt lost in surface outflow in summer was more than restored by the tides by the end of 1957. Deep salinities did not change between 1951 and 1962. Vertical attenuation of light is adequately accounted for by chlorophyll alone. The lake is much warmer than the nearby sea. Temperature inversions are caused by cold tidal water and perpetuated by vertical stability. The gross annual heat budget in 1957 was 22,000 cal/cm2, about the same as in the nearby sea, but higher than in a freshwater lake. Heating from below a few meters to 30 m can be accounted for by radiation alone. About 20% of radiation reaching the bottom subsequently appeared as heat in the water immediately overlying the bottom, thus implying restricted horizontal transfer. Oxygen was absent below 25–32.5 m, which may approximate the compensation level in this and similar lakes. Oxygen differences between basins are partly controlled by morphometry. Distinct oxygen minima in 1957 were associated with temperature minima and caused by concentrations of zooplankton. Vertical distribution of pH parallels that of oxygen. Specific alkalinities seem slightly higher than in normal seawater. Phosphate showed a distinct and stable minimum just above the anoxic layer and was as high as 14.3 μg-at/liter within that layer. Nitrate was relatively low and maximal just above the anoxic layer. Although nutrient levels seemed partly related to morphometry in the three basins, no evidence of nutrient enrichment of bottom water was found in late summer. The tides contribute negligible nutrients to the lake. The character of Ogac Lake compared with similar lakes derives from the great tidal amplitude and narrow connection with the sea, as well as from its small size and sheltered setting.

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