Monitoring Large-Scale Inland Water Dynamics by Fusing Sentinel-1 SAR and Sentinel-3 Altimetry Data and by Analyzing Causal Effects of Snowmelt

The warming climate is threatening to alter inland water resources on a global scale. Within all waterbody types, lake and river systems are vital not only for natural ecosystems but, also, for human society. Snowmelt phenology is also altered by global warming, and snowmelt is the primary water supply source for many river and lake systems around the globe. Hence, (1) monitoring snowmelt conditions, (2) tracking the dynamics of snowmelt-influenced river and lake systems, and (3) quantifying the causal effect of snowmelt conditions on these waterbodies are critical to understand the cryo-hydrosphere interactions under climate change. Previous studies utilized in-situ or multispectral sensors to track either the surface areas or water levels of waterbodies, which are constrained to small-scale regions and limited by cloud cover, respectively. On the contrary, in the present study, we employed the latest Sentinel-1 synthetic aperture radar (SAR) and Sentinel-3 altimetry data to grant a high-resolution, cloud-free, and illumination-independent comprehensive inland water dynamics monitoring strategy. Moreover, in contrast to previous studies utilizing in-house algorithms, we employed freely available cloud-based services to ensure a broad applicability with high efficiency. Based on altimetry and SAR data, the water level and the water-covered extent (WCE) (surface area of lakes and the flooded area of rivers) can be successfully measured. Furthermore, by fusing the water level and surface area information, for Lake Urmia, we can estimate the hypsometry and derive the water volume change. Additionally, for the Brahmaputra River, the variations of both the water level and the flooded area can be tracked. Last, but not least, together with the wet snow cover extent (WSCE) mapped with SAR imagery, we can analyze the influence of snowmelt conditions on water resource variations. The distributed lag model (DLM) initially developed in the econometrics discipline was employed, and the lagged causal effect of snowmelt conditions on inland water resources was eventually assessed.

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Assessment of water levels and the effects of climatic factors and catchment dynamics in a shallow subtropical reservoir, Manjirenji Dam, Zimbabwe

Journal of Water and Climate Change ◽

10.2166/wcc.2018.134 ◽

2018 ◽

Vol 10 (3) ◽

pp. 580-590 ◽

Cited By ~ 2

Author(s):

Beaven Utete ◽

Tamuka Nhiwatiwa ◽

Blessing Kavhu ◽

Samuel Kusangaya ◽

Nyashadzashe Viriri ◽

...

Keyword(s):

Water Resources ◽

Water Level ◽

Climatic Factors ◽

Integrated Water Resources Management ◽

Water Levels ◽

Water Level Fluctuations ◽

Management Approach ◽

Aquatic Communities ◽

Resources Management ◽

Conservation Implications

Abstract Natural water level fluctuations have associated effects on water quality and resident aquatic communities, although their impacts are magnified if the dams have other non-seasonal designated multiple uses. Research demonstrates that excessive water level fluctuations impair ecosystem functioning, ultimately leading to shifts between clear-water and turbid states in shallow lakes. However, these data lack for Manjirenji Dam in Zimbabwe, thus hampering efforts towards effective freshwater resources management in the shallow reservoir. This study analyzed water levels and their fluctuations, and assessed the effects of climatic factors and catchment dynamics using a combination of historical and remote sensed data for the shallow Manjirenji Dam in Zimbabwe. Time series and multiple regression analysis were used to determine water level trends, and the influence of catchment and climatic components in Manjirenji Dam. Lake levels have increased since construction, though their non-significant seasonal variation in the Manjirenji Dam reflects the overlapping effects of catchment and climatic variables. Despite the inferred high stability and resilience, the high fluctuation widths expose the dam to hydrodynamic and climate shocks which have major ecological and conservation implications. A climate change based integrated water resources management approach is necessary for sustainable water resources utilisation in the Manjirenji Dam.

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Wahania poziomów wody jezior w Polsce w latach 1956–2015 = Water-level fluctuations in Polish lakes in the 1956–2015 period

Przegląd Geograficzny ◽

10.7163/przg.2020.1.3 ◽

2020 ◽

Vol 92 (1) ◽

pp. 41-54

Author(s):

Adam Choiński ◽

Jerzy Jańczak ◽

Ptak Mariusz

Keyword(s):

Water Resources ◽

Water Level ◽

Climatic Factors ◽

Kendall Test ◽

Climatic Conditions ◽

Water Levels ◽

Water Level Fluctuations ◽

Anthropogenic Factors ◽

Local Conditions ◽

Study Results

Water-level fluctuations are among the primary factors determining the functioning of lakes. The volume to which lake basins are filled with water is of major importance to the courses of many processes and phenomena. A particular amount of water in a lake, and water-table stability, are also important from the point of view of human activity, as these elements help determine the quantity and accessibility of the water resources lakes have to offer, and therefore the possibilities for them to be used by different branches of the economy, e.g. industry, agriculture or tourism. The work detailed here is thus a presentation of trends as regards water-level fluctuations in 16 lakes in Poland, over the period 1956–2015. The study results, obtained for the first time in relation to such a long time scale and extending to around a dozen lakes, aim to point to the scale and direction of water-level fluctuations in times of the intensive transformation of the natural environment. They were obtained by reference to water-level observations made by the Institute of Meteorology and Water Management – National Research Institute (IMiGW-PIB). Specifically, data referring to the (November-October) hydrological year were analysed for trends as regards mean annual water levels using the Mann-Kendall test. Results point to major variability in the courses noted for these levels over the analysed multiannual period. Nevertheless, three overall situations could be designated from within the group of cases analysed, i.e. increase, decrease or lack of a trend. The first group includes Lakes Sławskie, Jamno, Łebsko, Nidzkie, and Studzieniczne (where increases were statistically significant at p=0.05); the second, Lakes Ostrzyckie and Ełckie (decreases significant at p=0.05); and the last group all remaining lakes, i.e. Charzykowskie, Jeziorak and Rajgrodzkie, Biskupińskie, Drwęckie and Białe, Gopło, Roś, and Wigry. It was, however, noted that in many cases analysed periods of alternating increase and decrease in water level were to be observed. The causes of such fluctuations were complex, but inter alia reflected droughts of several years’ duration, periods featuring higher-than-average precipitation, and local conditions. In general, water-level fluctuations in lakes result from natural and anthropogenic factors determining the hydrological conditions in catchments. And in the context of the lakes considered here, the courses of water-level fluctuations were mostly a reflection of local, rather than wider climatic conditions – a fact i.a. illustrated by the lack of cohesive regional designations. The situation is different from that of, for example, the thermal or ice regimes of Polish lakes, in relation to which observed similarities in properties are seen to be determined mainly by climatic factors. Information of this kind may be of key importance to the (quantitative and qualitative) management of water resources in the context of the climate change being observed currently.

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ICESat-2 Reservoir Applications: A case study from the largest man-made reservoir in India

10.31223/x5dk9d ◽

2021 ◽

Author(s):

Surajit Ghosh ◽

Atul Kaushik

Keyword(s):

Water Level ◽

Water Levels ◽

Water Bodies ◽

Reservoir Water ◽

Reservoir Water Level ◽

Reservoir Storage ◽

Inland Water ◽

Change Impact ◽

And Performance ◽

Inland Water Bodies

Monitoring inland water levels is crucial for understanding hydrological processes to climate change impact leading to policy implementation. Satellite altimetry has proved to be an excellent technique to precisely measure water levels of rivers, lakes, and other inland water bodies. The ATL13 product of ICESat-2 space-borne LiDAR is solely dedicated to inland water bodies. The water surface heights were derived from ICESat-2's strong beams, and performance was assessed with respect to reservoir gauge observations. Statistical measurements were used to understand the agreement (R2= 0.99, %RMSE=0.08) among the datasets. An R2 value of 0.99 was observed between ICESat-2 derived water level anomaly and the reservoir storage anomaly. This study provides a unique opportunity to utilize the ATL13 data product to study reservoir water level variation and estimate the reservoir's storage. The methodology can also be helpful to understand the reservoir storage variation in a data-sparse region.

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Changing Water Levels in Lake Superior, MI (USA) Impact Periphytic Diatom Assemblages in the Keweenaw Peninsula

Water ◽

10.3390/w13030253 ◽

2021 ◽

Vol 13 (3) ◽

pp. 253

Author(s):

M. Megan Woller-Skar ◽

Alexandra Locher ◽

Ellen Audia ◽

Evan W. Thomas

Keyword(s):

Water Level ◽

Surface Area ◽

Lake Superior ◽

Water Levels ◽

Ecological Processes ◽

Periphyton Community ◽

Water Level Changes ◽

Community Assemblages ◽

Keweenaw Peninsula ◽

The Impact

Predicted climate-induced changes in the Great Lakes include increased variability in water levels, which may shift periphyton habitat. Our goal was to determine the impacts of water level changes in Lake Superior on the periphyton community assemblages in the Keweenaw Peninsula with different surface geology. At three sites, we identified periphyton assemblages as a function of depth, determined surface area of periphyton habitat using high resolution bathymetry, and estimated the impact of water level changes in Lake Superior on periphyton habitat. Our results suggest that substrate geology influences periphyton community assemblages in the Keweenaw Peninsula. Using predicted changes in water levels, we found that a decrease in levels of 0.63 m resulted in a loss of available surface area for periphyton habitat by 600 to 3000 m2 per 100 m of shoreline with slopes ranging 2 to 9°. If water levels rise, the surface area of substrate will increase by 150 to 370 m2 per 100 m of shoreline, as the slopes above the lake levels are steeper (8–20°). Since periphyton communities vary per site, changes in the surface area of the substrate will likely result in a shift in species composition, which could alter the structure of aquatic food webs and ecological processes.

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Multivariate statistical modelling of extreme coastal water levels and the effect of climate variability: a case study in the Netherlands

10.5194/hess-2020-536 ◽

2020 ◽

Author(s):

Victor M. Santos ◽

Mercè Casas-Prat ◽

Benjamin Poschlod ◽

Elisa Ragno ◽

Bart van den Hurk ◽

...

Keyword(s):

Time Series ◽

Water Level ◽

Climate Model ◽

Regional Climate ◽

Water Levels ◽

Multivariate Statistical ◽

Inland Water ◽

Impact Function ◽

The Impact

Abstract. The co-occurrence of (not necessarily extreme) precipitation and surge can lead to extreme inland water levels in coastal areas. In a previous work the positive dependence between the two meteorological drivers was demonstrated in a case study in the Netherlands by empirically investigating an 800-year time series of water levels, which were simulated via a physical-based hydrological model driven by a regional climate model large ensemble. In this study, we present and test a multivariate statistical framework to replicate the demonstrated dependence and the resulting return periods of inland water levels. We use the same 800-year data series to develop an impact function, which is able to empirically describe the relationship between high inland water levels (the impact) and its driving variables (precipitation and surge). In our study area, this relationship is complex because of the high degree of human management affecting the dynamics of the water level. By event sampling and conditioning the drivers, an impact function was created that can reproduce the water levels maintaining an unbiased performance at the full range of simulated water levels. The dependence structure between the driving variables is modeled using two- and three-dimensional copulas. These are used to generate paired synthetic precipitation and surge events, transformed into inland water levels via the impact function. The compounding effects of surge and precipitation and the return water level estimates fairly well reproduce the earlier results from the empirical analysis of the same regional climate model ensemble. The proposed framework is therefore able to produce robust estimates of compound extreme water levels for a highly managed hydrological system. In addition, we present a unique assessment of the uncertainty when using only 50 years of data (what is typically available from observations). Training the impact function with short records leads to a general underestimation of the return levels as water level extremes are not well sampled. Also, the marginal distributions of the 50-year time series of the surge show high variability. Moreover, compounding effects tend to be underestimated when using 50 year slices to estimate the dependence pattern between predictors. Overall, the internal variability of the climate system is identified as a major source of uncertainty in the multivariate statistical model.

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Closure of Lake Nasser Khores by Different Types of Dams, using Satellite Images

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.c5221.029320 ◽

2020 ◽

Vol 9 (3) ◽

pp. 2095-2103

Keyword(s):

Water Resources ◽

Surface Area ◽

High Water ◽

Water Levels ◽

Large Area ◽

Artificial Lake ◽

Cost Study ◽

Lake Nasser ◽

Evaporation Losses ◽

Different Types

According to the agreement between Egypt and Sudan in 1959 for the full utilization of Nile water arriving Aswan, both countries agreed to build the High Aswan Dam (HAD) in 1964 to get benefits from the water which was flowing to the Mediterranean Sea. Therefore, Lake Nasser, the greatest artificial lake in the world, was created with large areas of shallow depths adjacent to the edges of the lake on both sides according to the topography of the surrounding area namely (khores). These khores increased the surface area; consequently, the estimated evaporation losses reach about 10 BCM/year in average. Reducing evaporation losses from HAD Lake is an option to increase the Egyptian available water resources. Many studies were done in order to partially or completely closure of the Khores, where the surface area of the khores of Lake Nasser is about one third of the total area of the lake, which indicates the effectiveness of its closure in decreasing the evaporation. The objectives of the research are studying the Lake Nasser’s large area khores, evaluating the idea of closing these khores using different types of dams such as earthfill, rockfill and rubber dams, and the consequent saved water. Meanwhile, a preliminary cost study for the different types of dams was done to determine the most suitable dam type. This research used the land sat 4 & 5 at years 1988 and 1999 in order to identify the surface area of the lake for the lowest and highest levels respectively. Also it gets benefit from the data available at Ministry of water Resources and Irrigation (MWRI), such as the Khores bathymetric maps and the evaporation rates of Lake Nasser. The results of the study show that Kalabsha khore is the most optimum for dam closure as its entrance is suitable for dam construction, and at high water levels it has the greatest area thus, reducing the evaporation. It is highly appreciated to use rubber dam either economically or environmentally. The amount of saved water reach about 1.0 Milliard m3 representing 11.11% of the annual total evaporation losses from Lake Nasser, the water saved may reach 1.53 Milliard m3 if the water level reaches 181.52 m for considerable time span.

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Visualization of Lake Mead Surface Area Changes from 1972 to 2009

10.32920/14639064.v1 ◽

2021 ◽

Author(s):

K. Wayne Forsythe ◽

Barbara Schatz ◽

Stephen J. Swales ◽

Lisa-Jen Ferrato ◽

David M. Atkinson

Keyword(s):

United States ◽

Water Level ◽

Surface Area ◽

Satellite Images ◽

Strong Relationship ◽

The United States ◽

Water Levels ◽

Lake Area ◽

Lake Mead ◽

Landsat Satellite

For most of the last decade, the south-western portion of the United States has experienced a severe and enduring drought. This has caused serious concerns about water supply and management in the region. In this research, 30 orthorectified Landsat satellite images from the United States Geological Service (USGS) Earth Explorer archive were analyzed for the 1972 to 2009 period. The images encompassed Lake Mead (a major reservoir in this region) and were examined for changes in water surface area. Decadal lake area minimums/maximums were achieved in 1972/1979, 1981/1988, 1991/1998, and 2009/2000. The minimum lake area extent occurred in 2009 (356.4 km2), while the maximum occurred in 1998 (590.6 km2). Variable trends in water level and lake area were observed throughout the analysis period, however progressively lower values were observed since 2000. The Landsat derived lake areas show a very strong relationship with actual measured water levels at the Hoover Dam. Yearly water level variations at the dam vary minimally from the satellite derived estimates. A complete (yearly) record of satellite images may have helped to reduce the slight deviations in the time series.

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Effects of Climate Changes on Water Resources: A Case of Mindu Dam in Morogoro Municipality, Tanzania

Tanzania Journal of Science ◽

10.4314/tjs.v47i3.33 ◽

2021 ◽

Vol 47 (3) ◽

pp. 1252-1265

Author(s):

Simon R Melchioly

Keyword(s):

Climate Change ◽

Water Resources ◽

Water Level ◽

Surface Area ◽

Secondary Data ◽

Climate Change Impacts ◽

Coefficient Of Determination ◽

Landsat 8 ◽

Climate Data ◽

Dam Reservoir

This paper presents the findings of the research conducted in Morogoro Municipality, central Tanzania. The main objective of the research was to assess the climate change impacts on water resources, taking the Mindu Dam as the case study. The study methodology involved collection, processing and analysis of both primary and secondary data. Data collection involved acquisition of Dam water level data, climate data, and Landsat 8 satellite imagery. Research findings showed that the maximum air temperature increased at a rate of 0.045% on a span of 30 years, while rainfall has been decreasing with time. Also there has been a decreasing trend of water level in the Mindu Dam such that the coefficient of determination (R2) appeared to be very small (0.95%). The area also has witnessed an increasing trend in wind speed (R2 = 63.4%) for the period 2014 to 2019. The results showed coefficient of determination (R2) for water production/supply of only 1.58%, while for water demand the coefficient of determination was R2 = 77.13%. Findings on the changes in surface area covered by the Mindu Dam reservoir due to climate change impacts showed that for the period of 19 years, the Mindu Dam reservoir surface area decreased by 0.57%. Keywords: Climate change; water resources; Mindu Dam; land use change

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Statistical modelling and climate variability of compound surge and precipitation events in a managed water system: a case study in the Netherlands

Hydrology and Earth System Sciences ◽

10.5194/hess-25-3595-2021 ◽

2021 ◽

Vol 25 (6) ◽

pp. 3595-3615

Author(s):

Víctor M. Santos ◽

Mercè Casas-Prat ◽

Benjamin Poschlod ◽

Elisa Ragno ◽

Bart van den Hurk ◽

...

Keyword(s):

Water Level ◽

Climate Model ◽

Regional Climate ◽

Water System ◽

Water Levels ◽

Multivariate Statistical ◽

Inland Water ◽

Impact Function ◽

Return Levels ◽

The Impact

Abstract. The co-occurrence of (not necessarily extreme) precipitation and surge can lead to extreme inland water levels in coastal areas. In a previous work the positive dependence between the two meteorological drivers was demonstrated in a managed water system in the Netherlands by empirically investigating an 800-year time series of water levels, which were simulated via a physical-based hydrological model driven by a regional climate model large ensemble. In this study, we present an impact-focused multivariate statistical framework to model the dependence between these flooding drivers and the resulting return periods of inland water levels. This framework is applied to the same managed water system using the aforementioned large ensemble. Composite analysis is used to guide the selection of suitable predictors and to obtain an impact function that optimally describes the relationship between high inland water levels (the impact) and the explanatory predictors. This is complex due to the high degree of human management affecting the dynamics of the water level. Training the impact function with subsets of data uniformly distributed along the range of water levels plays a major role in obtaining an unbiased performance. The dependence structure between the defined predictors is modelled using two- and three-dimensional copulas. These are used to generate paired synthetic precipitation and surge events, transformed into inland water levels via the impact function. The compounding effects of surge and precipitation and the return water level estimates fairly well reproduce the earlier results from the empirical analysis of the same regional climate model ensemble. Regarding the return levels, this is quantified by a root-mean-square deviation of 0.02 m. The proposed framework is able to produce robust estimates of compound extreme water levels for a highly managed hydrological system. Even though the framework has only been applied and validated in one study area, it shows great potential to be transferred to other areas. In addition, we present a unique assessment of the uncertainty when using only 50 years of data (what is typically available from observations). Training the impact function with short records leads to a general underestimation of the return levels as water level extremes are not well sampled. Also, the marginal distributions of the 50-year time series of the surge show high variability. Moreover, compounding effects tend to be underestimated when using 50-year slices to estimate the dependence pattern between predictors. Overall, the internal variability of the climate system is identified as a major source of uncertainty in the multivariate statistical model.

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Densified multi-mission observations by developed optical water levels show marked increases in lake water storage and overflow floods on the Tibetan Plateau

10.5194/essd-2019-34 ◽

2019 ◽

Author(s):

Xingdong Li ◽

Di Long ◽

Qi Huang ◽

Pengfei Han ◽

Fanyu Zhao ◽

...

Keyword(s):

Tibetan Plateau ◽

Water Level ◽

Lake Water ◽

Water Storage ◽

Water Levels ◽

The Tibetan Plateau ◽

Altimetry Data ◽

Data Set ◽

Lake Water Level ◽

And Storage

Abstract. The Tibetan Plateau (TP) known as Asia's water towers is quite sensitive to climate change, reflected by changes in hydrological state variables such as lake water storage. Given the extremely limited ground observations on the TP due to the harsh environment and complex terrain, we exploited multisource remote sensing, i.e., multiple altimetric missions and Landsat archives to create dense time series (monthly and even higher such as 10 days on average) of lake water level and storage changes across 52 large lakes (> 100 km2) on the TP during 2000–2017 (the data set is available online with a DOI: https://doi.org/10.1594/PANGAEA.898411). Field experiments were carried out in two typical lakes to validate the remotely sensed results. With Landsat archives and partial altimetry data, we developed optical water levels that cover most of TP lakes and serve as an ideal reference for merging multisource lake water levels. The optical water levels show an uncertainty of ~ 0.1 m that is comparable with most altimetry data and largely reduce the lack of dense altimetric observations with systematic errors well removed for most of lakes. The densified lake water levels provided critical and accurate information on the long-term and short-term monitoring of lake water level and storage changes on the TP. We found that the total storage of the 52 lakes increased by 97.3 km3 at two stages, i.e., 6.68 km3/yr during 2000–2012 and 2.85 km3/yr during 2012–2017. The total overflow from Lake Kusai to Lake Haidingnuoer and Lake Salt during Nov 9–Dec 31 in 2011 was estimated to be 0.22 km3, providing critical information on lake overflow flood monitoring and prediction as the expansion of some TP lakes becomes a serious threat to surrounding residents and infrastructure.

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