Comparison of SEBS and SEBAL Algorithms in Evaporation Estimation from Open Water Surface with the Assessment of the Salinity Effect

The effects of ice on the conveyance characteristics of the Mackenzie River at the outlet of Great Slave Lake are modeled on the basis of cross section surveys, discharge measurements, and water surface profiles taken during open water and ice covered conditions. The calibrated bed roughness values, expressed in terms of Mannings n, range from 0.020 to 0.030. Based on measured ice thicknesses ranging from 0.6 to 1.2 m in the study reach upstream of Providence Narrows, the calibrated roughness of the 1992 late winter ice cover is 0.015. Discharge estimates, based on this late winter ice cover calibration, measured water surface profiles, and documentation of major ice movements during April and May of 1992, show relatively good agreement with the discharge measurements taken at the same time. The analysis indicates that flow in the channel just downstream of Great Slave Lake is uniform under both open water and ice covered conditions. However, stage–discharge relationships at the Water Survey of Canada gauging station are affected by variable backwater conditions, particularly when an ice accumulation develops in Providence Rapids. Key words: ice, breakup, backwater curves, hydraulic resistance, river.

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Evaporation suppression from open water surface using various floating covers with consideration of water ecology

Journal of Hydrology ◽

10.1016/j.jhydrol.2021.126482 ◽

2021 ◽

pp. 126482

Author(s):

Maram M. Shalaby ◽

Ibrahim N. Nassar ◽

Ahmed M. Abdallah

Keyword(s):

Water Surface ◽

Open Water ◽

Evaporation Suppression ◽

Water Ecology

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Water Surface Overgrowing of the Tatra’s Lakes

Ekológia (Bratislava) ◽

10.2478/eko-2018-0002 ◽

2018 ◽

Vol 37 (1) ◽

pp. 11-23 ◽

Cited By ~ 2

Author(s):

Juraj Kapusta ◽

Juraj Hreško ◽

František Petrovič ◽

Dávid Tomko-Králo ◽

Jozef Gallik

Keyword(s):

Water Surface ◽

Open Water ◽

Rapid Expansion ◽

Peat Bogs ◽

Vegetation Zone ◽

Fine Sediments ◽

Significant Phenomenon ◽

The High Tatras ◽

Alpine Landscape ◽

Lake Basins

AbstractTatra’s lakes are vulnerable ecosystems and an important element of the alpine landscape. Mainly some shallow lake basins succumb to intense detritus sedimentation, fine fractions of material from the catchment area or to the overgrowing of water level by vegetation. In this paper, changes and dynamics of the 12 Tatra’s lake shorelines that were selected based on the detailed mapping of their extent are pointed out. Changes were assessed by accurate comparisons of historical and current orthophoto maps from the years 1949, 1955 and 2015 – and therefore, based on the oldest and the latest relevant materials. Due to the overgrowing of lakes caused by vegetation, their water surface decreased from −0.9% up to −47.9%, during the examined period. Losses were caused by the overgrowing of open water surface by the communities of sedges and peat bogs. The most significant dynamics of the shorelines during the last decades were reached by those lakes, into which fine sediments were simultaneously deposited by means of mountain water coarse. These sediments made the marginal parts of the lake basins shallower and accelerated rapid expansion of vegetation to the detriment of the open water surface. The overgrowing of shallow moraine lakes lying in the vegetation zone is a significant phenomenon of the High Tatras alpine landscape. It leads to their gradual extinction, turn into peat bogs and wet alpine meadows.

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Abundance of Atlantic walrus in Western Nares Strait, Baffin Bay Stock, during summer

NAMMCO Scientific Publications ◽

10.7557/3.2611 ◽

2014 ◽

Vol 9 ◽

pp. 123 ◽

Cited By ~ 5

Author(s):

Robert EA Stewart ◽

Erik W Born ◽

Rune Dietz ◽

Mads Peter Heide-Jørgensen ◽

Frank Farsø Rigét ◽

...

Keyword(s):

Water Surface ◽

Open Water ◽

Ellesmere Island ◽

Baffin Bay ◽

Nares Strait ◽

The North ◽

North Water Polynya ◽

Odobenus Rosmarus ◽

North Water ◽

Odobenus Rosmarus Rosmarus

Atlantic walruses (Odobenus rosmarus rosmarus) belonging to the Baffin Bay subpopulation occur year round in the North Water polynya (NOW) between NW Greenland and eastern Ellesmere Island (Canada). They are hunted for subsistence purposes by residents of the Qaanaaq area (NW Greenland) bordering the NOW to the east and by Canadian Inuit at the entrance to Jones Sound in Nunavut. During the open-water period NW Greenland is virtually devoid of walruses which concentrate along eastern and southern Ellesmere Island at this time of the year. To determine the abundance of walruses in the NOW area, aerial surveys were conducted in August of 1999, 2008, and 2009. In July 2009, nine satellite-linked transmitters were deployed in nearby Kane Basin. Surveys on 9 and 20 August 2009 along eastern Ellesmere Island were the most extensive and were augmented with concomitant data on haul-out and at water surface activity from three (1 F, 2 M) of the nine tags that were still functioning. We therefore focus on the 2009 surveys. Walruses were observed on the ice and in water primarily in Buchanan Bay and Princess Marie Bay where the remaining functional tags were located. The Minimum Counted population (MCP) was 571 on 20 August. Adjusting the MCP of walruses on ice for those not hauled out, the estimate of abundance of walruses in the Baffin Bay stock was 1,251(CV=1.00, 95% CI = 1,226) when adjusted by the proportion of tags ‘dry’ at the time of the survey and 1,249 (CV=1.12, 95% CI = 1,370) when adjusted by the average time tags were dry. The surveys did not cover all potential walrus summering habitat along eastern Ellesmere Island and are negatively biased to an unknown degree.

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Contemporary changes in open water surface area of Lake Inle, Myanmar

Sustainability Science ◽

10.1007/s11625-006-0020-7 ◽

2007 ◽

Vol 2 (1) ◽

pp. 55-65 ◽

Cited By ~ 26

Author(s):

Roy C. Sidle ◽

Alan D. Ziegler ◽

John B. Vogler

Keyword(s):

Surface Area ◽

Water Surface ◽

Open Water ◽

Water Surface Area

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Habitat Utilization of Gerris argentatus (Het. Gerridae)1

Insect Systematics & Evolution ◽

10.1163/187631274x00227 ◽

1974 ◽

Vol 5 (3-4) ◽

pp. 189-195 ◽

Cited By ~ 9

Author(s):

Olli Järvinen ◽

Kari Vepsäläinen

Keyword(s):

Water Surface ◽

Developmental Stages ◽

Habitat Preferences ◽

Open Water ◽

Habitat Utilization ◽

Size Classes ◽

Dense Vegetation

AbstractDifferent instars of Gerris argentatus Schumm. were most abundant each in a different habitat in a pond. The older stages were found on more open water surface than the younger ones. Totally open water was avoided. Hind femurs of G. argentatus and sympatric G. lacustris (L.) were measured. The ratio of the measurements of two subsequent developmental stages is about 1.3—1.6. The measurements of G. lacustris instars lie between those of different G. argentatus size classes. The observations are interpreted to indicate different habitat preferences. The length of the leg reflects ease of movement in dense vegetation, correlating with efficiency of foraging. Changes in abundance of the two species in the study pond are discussed.

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Potential evaporation dynamics over saturated bare soil and an open water surface

Journal of Hydrology ◽

10.1016/j.jhydrol.2020.125140 ◽

2020 ◽

Vol 590 ◽

pp. 125140

Author(s):

Wanxin Li ◽

Philip Brunner ◽

Harrie-Jan Hendricks Franssen ◽

Zhi Li ◽

Zhoufeng Wang ◽

...

Keyword(s):

Water Surface ◽

Open Water ◽

Bare Soil ◽

Potential Evaporation ◽

Evaporation Dynamics

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Present-day evolution of coastal lakes based on the example of Jamno and Bukowo (the Southern Baltic coast)

Oceanological and Hydrobiological Studies ◽

10.2478/s13545-014-0131-1 ◽

2014 ◽

Vol 43 (2) ◽

Cited By ~ 11

Author(s):

Adam Choiński ◽

Mariusz Ptak ◽

Agnieszka Strzelczak

Keyword(s):

Water Surface ◽

Open Water ◽

Aerial Photographs ◽

Direct Connection ◽

The Baltic Sea ◽

Coastal Lakes ◽

Baltic Coast ◽

Water Surface Area ◽

The Baltic ◽

Lake Basins

AbstractThis study presents the directions and the rate of changes occurring in the coastal lakes Jamno and Bukowo, located in northern Poland. Based on the cartographic materials and aerial photographs of those water bodies, it was established that in 1909–2012, the area of the lakes decreased by 183.6 ha (7.7%) and 250.7 ha (13.6%) for Jamno and Bukowo, respectively. Another component of lake disappearance — shallowing of lake basins — was analyzed using bathymetric plans. It turned out that water supplies of Jamno during more than 100 years decreased by 2.4 million m3 (5.9%), while in the case of Bukowo, it was 5.9 million (17.5%). Unfavorable location (inflow of pollutants from the basin) and morphometry of both lakes should be considered as the main causes of such major changes. The lakes are polymictic with a considerable area of the shallowest zone (1 m depth). This favors the vegetation succession and, consequently, shallowing of the lake basins. Moreover, direct connection with the Baltic Sea contributes to the fact that the materials of marine origin deposited in the form of a reverse delta also contribute to a decrease in the open water surface area.

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Providing a long-term hydroclimatic perspective for the recent extreme decline of Lake Prespa (SW Balkans) through quantitative reconstruction of lake water-balance changes over the past 5000 years

10.5194/ems2021-309 ◽

2021 ◽

Author(s):

Tim van der Schriek ◽

Christos Giannakopoulos

Keyword(s):

Climate Change ◽

Lake Water ◽

Water Loss ◽

Water Surface ◽

Lake Level ◽

Open Water ◽

Water Levels ◽

The Past ◽

Lake Water Balance

Ancient lakes throughout the Mediterranean are at risk of disappearing due to a combination of climate change and human impacts. The growing imbalance between water availability and demand is creating unprecedented ecological problems. There is an urgent need for better understanding the patterns of natural lake water variability to improve water resource management and conservation. The incorporation of long-term cycles is particularly important for assessing low frequency &#8211; high magnitude trends in lake water levels.The Ohrid-Prespa Lake system is amongst the oldest permanent lake systems in Europe, with an age of >1 million years, and hosts a globally significant biodiversity. The closed-basin Prespa Lakes are particularly sensitive to climatic variability with long-term water level changes informing on the dynamic balance between [1] runoff and precipitation supplying water to the lakes, and [2] water loss from the lakes by evaporation and underground karst outflow.The large, ongoing, fall of the Prespa Lakes that started in 1987 threatens the biodiversity and water resources of the interconnected lake system. This decline is caused by climate change, specifically by decreases of 10% in precipitation and 25% in runoff, amplified by water abstraction. There is no precedent for this water level fall in the observational record (1951-present), although geological archives indicate equally low water levels at least twice over the past five millennia.&#160;Here we present the first quantified estimates of changes in the lake water balance over time that are based on the strong relationship between open water surface area and water loss. This quantification allows direct comparison of lake low- and highstand events across time and assessing magnitudes of regional hydro-climatic changes. This study uses a novel approach that reconstructs absolute lake levels and related open water surface areas for different past periods, using the landform-sediment record.The hydro-climate of the Prespa catchment shows a drying trend of since the mid Holocene. The recent (2001-2018) lake lowstand is the most significant over the past 700 years in terms of water loss changes. A lake lowstand period of a similar magnitude occurred about 2000 years ago. The most extreme lowstand period over the past 5000 years occurred between 1100-800 years ago during the Medieval Climate Anomaly, when water loss changes were >50% higher compared to the present lowstand. However, the renewed decline in lake level and surface area since 2019 requires close monitoring; if lake level falls a further 2m to 840m.a.s.l. it would become the largest recorded fall over the entire Holocene, with unknown impacts for the wider system.&#160;

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