Monitoring Long-Term Lake Level Variations in Middle and Lower Yangtze Basin over 2002–2017 through Integration of Multiple Satellite Altimetry Datasets

Satellite altimetry has been effectively used for monitoring lake level changes in recent years. This work focused on the integration of multiple satellite altimetry datasets from ICESat-1, Envisat and Cryosat-2 for the long-term (2002–2017) observation of lake level changes in the middle and lower Yangtze River Basin (MLYB). Inter-altimeter biases were estimated by using the gauged daily water level data. It showed that the average biases of ICESat-1 and Cryosat-2 with respect to Envisat were 6.7 cm and 3.1 cm, respectively. The satellite-derived water levels were evaluated against the gauged data. It indicated significantly high correlations between the two datasets, and the combination of three altimetry data produced precise water level time series with high temporal and spatial resolutions. A liner regression model was used to estimate the rates of lake level changes over the study period after the inter-altimeter bias adjustment was performed. The results indicated that ~79% of observed lakes (41/52) showed increasing trends in water levels with rates up to 0.203 m/y during 2002–2017. The temporal analysis of lake level variations suggested that ~60% of measured lakes (32/53) showed decreasing trends during 2002–2009 while ~66% of measured lakes (79/119) exhibited increasing trends during 2010–2017. Most of measured reservoirs displayed rapidly rising trends during the study period. The driving force analysis indicated that the temporal heterogeneity of precipitation can be mainly used to explain the observed pattern of lake level changes. The operation of reservoirs and human water consumption were also responsible for the lake level variations. This work demonstrated the potential of integrating multiple satellite altimeters for the long-term monitoring of lake levels, which can help to evaluate the impact of climate change and anthropogenic activities on regional water resources.

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Sedimentary Cladocera as indicators of past water-level changes in shallow northern lakes

Quaternary Research ◽

10.1016/j.yqres.2011.02.007 ◽

2011 ◽

Vol 75 (3) ◽

pp. 430-437 ◽

Cited By ~ 33

Author(s):

Liisa Nevalainen ◽

Kaarina Sarmaja-Korjonen ◽

Tomi P. Luoto

Keyword(s):

Water Level ◽

Lake Level ◽

Water Levels ◽

Sediment Record ◽

Inference Model ◽

Water Level Changes ◽

Long Term Changes ◽

Lower Water Level ◽

The Relationship

AbstractThe usability of subfossil Cladocera assemblages in reconstructing long-term changes in lake level was examined by testing the relationship between Cladocera-based planktonic/littoral (P/L) ratio and water-level inference model in a surface-sediment dataset and in a 2000-yr sediment record in Finland. The relationships between measured and inferred water levels and P/L ratios were significant in the dataset, implying that littoral taxa are primarily deposited in shallow littoral areas, while planktonic cladocerans accumulate abundantly mainly in deepwater locations. The 2000-yr water-level reconstructions based on the water-level inference model and P/L ratio corresponded closely with each other and with a previously available midge-inferred water-level reconstruction from the same core, showing a period of lower water level around AD 300–1000 and suggesting that the methods are valid for paleolimnological and -climatological use.

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Validation of Sentinel-3A Based Lake Level over US and Canada

Remote Sensing ◽

10.3390/rs12172835 ◽

2020 ◽

Vol 12 (17) ◽

pp. 2835

Author(s):

Karina Nielsen ◽

Ole Baltazar Andersen ◽

Heidi Ranndal

Keyword(s):

Water Level ◽

Satellite Altimetry ◽

Lake Level ◽

Mean Squared Error ◽

Pearson Correlation ◽

The United States ◽

Water Levels ◽

Winter Period ◽

Large Lakes ◽

In Situ Data

Satellite altimetry is an important contributor for measuring the water level of continental water bodies. The technique has been applied for almost three decades. In this period the data quality has increased and the applications have evolved from the study of a few large lakes and rivers, to near global applications at various scales. Products from current satellite altimetry missions should be validated to continuously improve the measurements. Sentinel-3A has been operating since 2016 and is the first mission operating in synthetic aperture radar (SAR) mode globally. Here we evaluate its performance in capturing lake level variations based on a physical and an empirical retracker provided in the official level 2 product. The validation is performed for more than 100 lakes in the United States and Canada where the altimetry based water levels are compared with in situ data. As validation measures we consider the root mean squared error, the Pearson correlation, and the percentage of outliers. For the US sites the median of the RMSE value is 25 cm and 19 cm and the median of the Pearson correlations are 0.86 and 0.93 for the physical and empirical retracker, respectively. The percentage of outliers (median) is 11% for both retrackers. The validations measures are slightly poorer for the Canadian sites; the median RMSE is approximately 5 cm larger, the Pearson correlation 0.1 lower, and the percentage of outliers 5% larger. The poorer performance for the Canadian sites is mainly related to the presence of lake ice in the winter period where the surface elevations are not able to map the surface correctly. The validation measures improve considerably when evaluated for summer data only. For both areas we show that the reconstruction of the water level variations based on the empirical retracker is significantly better compared to that of the physical retracker in terms of the RMSE and the Pearson correlation.

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Effects of Lake level changes on water quality and fisheries production of Lake Baringo, Kenya

10.22541/au.162557458.89080739/v1 ◽

2021 ◽

Author(s):

Jacques Walumona ◽

Boaz Arara ◽

Cyprian Ogombe ◽

James Murakaru ◽

Phillip Raburu ◽

...

Keyword(s):

Water Quality ◽

Water Level ◽

Fish Species ◽

Lake Level ◽

Water Level Fluctuations ◽

Regression Analyses ◽

Lake Level Fluctuations ◽

Lake Level Changes ◽

Over Time

The study was conducted in Lake Baringo and determined quantitative relationships between water level changes, water quality, and fishery production for informed lake basin management. Long-term (2008 to 2020) data on water level, water quality, and fisheries yields from Lake Baringo were analyzed using a combination of statistical methods. Linear and waveform regression analyses described patterns of lake level fluctuations over time while, Pearson’s correlation determined the concordance of lake level changes with water quality parameters, landings, and condition of fish species. PCA results grouped the study period into different years based on annual water quality variable levels. LOWESS analysis showed the decline of annual lake level amplitude over time with peak values in 1964 (8.6 m) and 2008 (9.4 m). The waveform regression significantly modeled lake level fluctuations as indexed by annual deviations from the long-term average (DLTM) and showed a 20-year oscillation between peak water levels in the lake. There were significant positive correlations of Water Level Fluctuations (WLFs) with water quality variables and water quality index (WQI) in Lake Baringo. Linear regression analyses showed a significant concordance (p < 0.05) between the annual fishery yield and the rising WLFs (r = 0.66). Overall, the results demonstrate that WLFs of Lake Baringo are a driver of fish species biomass and physico-chemical properties of the lake. We recommend the integration of fisheries yields, water quality assessment, and WLFs modeling at different temporal scales in the management of Afrotropical lake ecosystems

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Recent Abnormal Hydrologic Behavior of Tibetan Lakes Observed by Multi-Mission Altimeters

Remote Sensing ◽

10.3390/rs12182986 ◽

2020 ◽

Vol 12 (18) ◽

pp. 2986

Author(s):

Pengfei Zhan ◽

Chunqiao Song ◽

Jida Wang ◽

Wenkai Li ◽

Linghong Ke ◽

...

Keyword(s):

Water Level ◽

Lake Level ◽

Average Rate ◽

Water Levels ◽

The Tibetan Plateau ◽

Important Indicator ◽

Water Level Rise ◽

Lake Level Changes ◽

Spatial Differences ◽

Climate Analysis

Inland lakes in the Tibetan Plateau (TP) with closed catchments and minimal human disturbance are an important indicator of climate change. However, the examination of changes in the spatiotemporal patterns of Tibetan lakes, especially water level variations, is limited due to inadequate access to measurements. This obstacle has been improved by the development of satellite altimetry observations. The more recent studies revealed that the trend of central TP to grow decreased or reversed between 2010 and 2016. However, thus far, this trend has not been investigated to determine whether this pattern would last for the following years. This study aims to combine the traditional (launched before 2010, e.g., TOPEX/POSEIDON, ERS-1, ERS-2, Jason-1/-2, and Envisat) and recently advanced (launched after 2010, e.g., SARAL and Sentinel-3) altimetry observations to understand the Tibetan lake changes further in recent years. Therefore, we acquired information on the continuous lake level changes in Tibetan lakes using the lake level sequence integration method based on multisource altimetry satellites. The results revealed that water level changes in 22 examined lakes showed abrupt rises in 2016–2018, but the onsets and magnitudes of the rises varied among the lakes. During the study period, the water levels of the lakes (except Nam Co) revealed a drastic rising tendency with a mean rate of 0.74 m/a, which was remarkably higher than the average rate of water level rise over the period 2010–2015 (approximately 0.28 m/a). Specifically, the water level of the nine lakes in the Northern TP (NTP) displayed a significant rising trend, with an average rate of 0.82 m/a. In the Central TP (CTP), the lake level changes were generally divided into two categories. The water levels for the lakes in the Western CTP rose rapidly, while, in the Eastern CTP, the lake water levels rose slowly, with an average rising rate less than 0.40 m/a. The water levels for the lakes in the Northeastern TP (NETP) and Northwestern TP (NWTP) kept a stable rising tendency. According to the results of the climate analysis, the spatial differences of the lake level rise rates were primarily caused by the spatial and temporal changes of precipitation over the TP.

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Assessing Stream-Aquifer Connectivity in a Coastal California Watershed

Water ◽

10.3390/w13040416 ◽

2021 ◽

Vol 13 (4) ◽

pp. 416

Author(s):

Bwalya Malama ◽

Devin Pritchard-Peterson ◽

John J. Jasbinsek ◽

Christopher Surfleet

Keyword(s):

Time Series ◽

Spectral Analysis ◽

Water Level ◽

Time Series Data ◽

Series Data ◽

Low Permeability ◽

Pumping Tests ◽

Stream Flows ◽

The Impact

We report the results of field and laboratory investigations of stream-aquifer interactions in a watershed along the California coast to assess the impact of groundwater pumping for irrigation on stream flows. The methods used include subsurface sediment sampling using direct-push drilling, laboratory permeability and particle size analyses of sediment, piezometer installation and instrumentation, stream discharge and stage monitoring, pumping tests for aquifer characterization, resistivity surveys, and long-term passive monitoring of stream stage and groundwater levels. Spectral analysis of long-term water level data was used to assess correlation between stream and groundwater level time series data. The investigations revealed the presence of a thin low permeability silt-clay aquitard unit between the main aquifer and the stream. This suggested a three layer conceptual model of the subsurface comprising unconfined and confined aquifers separated by an aquitard layer. This was broadly confirmed by resistivity surveys and pumping tests, the latter of which indicated the occurrence of leakage across the aquitard. The aquitard was determined to be 2–3 orders of magnitude less permeable than the aquifer, which is indicative of weak stream-aquifer connectivity and was confirmed by spectral analysis of stream-aquifer water level time series. The results illustrate the importance of site-specific investigations and suggest that even in systems where the stream is not in direct hydraulic contact with the producing aquifer, long-term stream depletion can occur due to leakage across low permeability units. This has implications for management of stream flows, groundwater abstraction, and water resources management during prolonged periods of drought.

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Quantifying recent lake level changes in Patagonia (Argentina and Chile): Back to the future?

10.5194/egusphere-egu21-8467 ◽

2021 ◽

Author(s):

Daniel Ariztegui ◽

Clément Pollier ◽

Andrés Bilmes

Keyword(s):

Water Level ◽

Lake Level ◽

Satellite Images ◽

Meteorological Data ◽

Tierra Del Fuego ◽

Water Level Fluctuations ◽

Lake Levels ◽

The Past ◽

Rainfall Variations ◽

The Impact

Lake levels in hydrologically closed-basins are very sensitive to climatically and/or anthropogenically triggered environmental changes. Their record through time can provide valuable information to forecast changes that can have substantial economical and societal impact.Increasing precipitation in eastern Patagonia (Argentina) have been documented following years with strong El Ni&#241;o (cold) events using historical and meteorological data. Quantifying changes in modern lake levels allow determining the impact of rainfall variations while contributing to anticipate the evolution of lacustrine systems over the next decades with expected fluctuations in ENSO frequencies. Laguna Carrilaufquen Grande is located in the intermontane Maquinchao Basin, Argentina. Its dimension fluctuates greatly, from 20 to 55 km2 water surface area and an average water depth of 3 m. Several well-preserved gravelly beach ridges witness rainfall variations that can be compared to meteorological data and satellite images covering the last ~50 years. Our results show that in 2016 lake level was the lowest of the past 44 years whereas the maximum lake level was recorded in 1985 (+11.8 m above the current lake level) in a position 1.6 km to the east of the present shoreline. A five-years moving average rainfall record of the area was calculated smoothing the extreme annual events and correlated to the determined lake level fluctuations. The annual variation of lake levels was up to 1.2 m (e.g. 2014) whereas decadal variations related to humid-arid periods for the interval 2002 to 2016 were up to 9.4 m. These data are consistent with those from other monitored lakes and, thus, our approach opens up new perspectives to understand the historical water level fluctuations of lakes with non-available monitoring data.&#160;Laguna de los Cisnes in the Chilean section of the island of Tierra del Fuego, is a closed-lake presently divided into two sections of 2.2 and 11.9 km2, respectively. These two water bodies were united in the past forming a single larger lake. The lake level was&#160; ca. 4 m higher than today as shown by clear shorelines and the outcropping of large Ca-rich microbialites. Historical data, aerial photographs and satellite images indicate that the most recent changes in lake level are the result of a massive decrease of water input during the last half of the 20th century triggered by an indiscriminate use of the incoming water for agricultural purposes. The spectacular outcropping of living and fossil microbialites is not only interesting from a scientific point of view but has also initiated the development of the site as a local touristic attraction. However, if the use of the incoming water for agriculture in the catchment remains unregulated the lake water level might drop dangerously and eventually the lake might fully desiccate.These two examples illustrate how recent changes in lake level can be used to anticipate the near future of lakes. They show that ongoing climate changes along with the growing demand of natural resources have already started to impact lacustrine systems and this is likely to increase in the decades to come.

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The implications of selected processing methods on satellite altimetry derived sea ice thickness state and trends in the seasonal ice zone

10.5194/egusphere-egu21-12240 ◽

2021 ◽

Author(s):

Isolde Glissenaar ◽

Jack Landy ◽

Alek Petty ◽

Nathan Kurtz ◽

Julienne Stroeve

Keyword(s):

Sea Ice ◽

Snow Depth ◽

Satellite Altimetry ◽

Region Of Interest ◽

The Arctic ◽

Ice Thickness ◽

Sea Ice Thickness ◽

Baffin Bay ◽

The Impact

The ice cover of the Arctic Ocean is increasingly becoming dominated by seasonal sea ice. It is important to focus on the processing of altimetry ice thickness data in thinner seasonal ice regions to understand seasonal sea ice behaviour better. This study focusses on Baffin Bay as a region of interest to study seasonal ice behaviour.We aim to reconcile the spring sea ice thickness derived from multiple satellite altimetry sensors and sea ice charts in Baffin Bay and produce a robust long-term record (2003-2020) for analysing trends in sea ice thickness. We investigate the impact of choosing different snow depth products (the Warren climatology, a passive microwave snow depth product and modelled snow depth from reanalysis data) and snow redistribution methods (a sigmoidal function and an empirical piecewise function) to retrieve sea ice thickness from satellite altimetry sea ice freeboard data.The choice of snow depth product and redistribution method results in an uncertainty envelope around the March mean sea ice thickness in Baffin Bay of 10%. Moreover, the sea ice thickness trend ranges from -15 cm/dec to 20 cm/dec depending on the applied snow depth product and redistribution method. Previous studies have shown a possible long-term asymmetrical trend in sea ice thinning in Baffin Bay. The present study shows that whether a significant long-term asymmetrical trend was found depends on the choice of snow depth product and redistribution method. The satellite altimetry sea ice thickness results with different snow depth products and snow redistribution methods show that different processing techniques can lead to different results and can influence conclusions on total and spatial sea ice thickness trends. Further processing work on the historic radar altimetry record is needed to create reliable sea ice thickness products in the marginal ice zone.

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Determining Extreme Still Water Levels for Design and Planning Purposes Incorporating Sea Level Rise: Sydney, Australia

Atmosphere ◽

10.3390/atmos13010095 ◽

2022 ◽

Vol 13 (1) ◽

pp. 95

Author(s):

Phil J. Watson

Keyword(s):

Sea Level Rise ◽

Water Level ◽

Sea Level ◽

Tide Gauge ◽

Water Levels ◽

Extreme Value Analysis ◽

Tide Gauge Record ◽

Value Analysis ◽

Mean Sea Level ◽

The Impact

This paper provides an Extreme Value Analysis (EVA) of the hourly water level record at Fort Denison dating back to 1915 to understand the statistical likelihood of the combination of high predicted tides and the more dynamic influences that can drive ocean water levels higher at the coast. The analysis is based on the Peaks-Over-Threshold (POT) method using a fitted Generalised Pareto Distribution (GPD) function to estimate extreme hourly heights above mean sea level. The analysis highlights the impact of the 1974 East Coast Low event and rarity of the associated measured water level above mean sea level at Sydney, with an estimated return period exceeding 1000 years. Extreme hourly predictions are integrated with future projections of sea level rise to provide estimates of relevant still water levels at 2050, 2070 and 2100 for a range of return periods (1 to 1000 years) for use in coastal zone management, design, and sea level rise adaptation planning along the NSW coastline. The analytical procedures described provide a step-by-step guide for practitioners on how to develop similar baseline information from any long tide gauge record and the associated limitations and key sensitivities that must be understood and appreciated in applying EVA.

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The Role of Mean Sea Level Annual Cycle on Extreme Water Levels Along European Coastline

Remote Sensing ◽

10.3390/rs12203419 ◽

2020 ◽

Vol 12 (20) ◽

pp. 3419

Author(s):

Tomás Fernández-Montblanc ◽

Jesús Gómez-Enri ◽

Paolo Ciavola

Keyword(s):

Water Level ◽

Sea Level ◽

North Sea ◽

Extreme Events ◽

Annual Cycle ◽

Coastal Flooding ◽

Water Levels ◽

Total Water ◽

Mean Sea Level ◽

The Impact

The knowledge of extreme total water levels (ETWLs) and the derived impact, coastal flooding and erosion, is crucial to face the present and future challenges exacerbated in European densely populated coastal areas. Based on 24 years (1993–2016) of multimission radar altimetry, this paper investigates the contribution of each water level component: tide, surge and annual cycle of monthly mean sea level (MMSL) to the ETWLs. It focuses on the contribution of the annual variation of MMSL in the coastal flooding extreme events registered in a European database. In microtidal areas (Black, Baltic and Mediterranean Sea), the MMSL contribution is mostly larger than tide, and it can be at the same order of magnitude of the surge. In meso and macrotidal areas, the MMSL contribution is <20% of the total water level, but larger (>30%) in the North Sea. No correlation was observed between the average annual cycle of monthly mean sea level (AMMSL) and coastal flooding extreme events (CFEEs) along the European coastal line. Positive correlations of the component variance of MMSL with the relative frequency of CFEEs extend to the Central Mediterranean (r = 0.59), North Sea (r = 0.60) and Baltic Sea (r = 0.75). In the case of positive MMSL anomalies, the correlation expands to the Bay of Biscay and northern North Atlantic (at >90% of statistical significance). The understanding of the spatial and temporal patterns of a combination of all the components of the ETWLs shall improve the preparedness and coastal adaptation measures to reduce the impact of coastal flooding.

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Explicit Finite Element Study of Liquid Sloshing Behavior in Fluid-Structure Interaction Condition

Volume 7: Fluids Engineering ◽

10.1115/imece2017-70832 ◽

2017 ◽

Author(s):

Shuo Yang ◽

Raymond K. Yee

Keyword(s):

Finite Element ◽

Water Level ◽

Similarity Theory ◽

Fluid Structure Interaction ◽

Water Levels ◽

Tank Wall ◽

Fluid Structure ◽

Structure Interaction ◽

Sloshing Phenomenon ◽

The Impact

As a common phenomenon in liquid motions, sloshing usually happens in a partially filled liquid tank of moving vehicle or structure. The objectives of this paper are to study sloshing behavior in rigid tank and deformable tank, and to develop a better performance baffle design in the tank under seismic excitations. The tank is surged with a sinusoidal oscillation about horizontal x-direction. The hydro-elasticity effect of sloshing pressure on the tank wall was taken into consideration due to the fluid-structure interaction between impact pressures and tank structures. ABAQUS finite element program using Coupled Eulerian-Lagrangian (CEL) technique was employed to simulate fluid sloshing. The sloshing phenomenon was studied in rigid tank and deformable tank models with three different water levels, and the effect of wall thickness of the deformable tank on sloshing behavior was discussed. One way to minimize the effect of sloshing in a tank, baffles are used and installed in the middle of the tank, and then various heights and material types of baffle were evaluated. The simulation results show that higher water level case creates greater pressure impact on the tank wall than lower water level case, and the elasticity of the tank structure would reduce the impact pressure of the wall. For the simulation tank model with size of 1m (H) × 1m (W) × 0.2m (D), better performance baffle was found to be the one with the height of 0.35m and was made of acrylic material. Moreover, the conclusion of this study can be extrapolated to other dimensions of the model based on similarity theory. This paper also can serve as an aid in further studying sloshing phenomenon. The findings of this study can be applied to restrain or minimize sloshing motions inside a tank.

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