Detection and Attribution of Lake Victoria’s Water-Level Fluctuations in a Changing Climate

This study investigated the influence of land-use and precipitation change and variability on Lake Victoria’s water-level fluctuations. Extreme precipitation events, corresponding to extreme water-levels, over the lake and its catchment area were identified and their return periods estimated by fitting them into a generalized extreme value (GEV) distribution. Using general circulation models from the 6th phase of the Coupled Model Intercomparison Project (CMIP6)’s Detection & Attribution Model Intercomparison Project (DAMIP), an assessment of the potential contribution of human-induced climate change on the observed precipitation patterns over the study area was done. The greatest precipitation anomalies for the period 1900-2020 were recorded in 1961’s October-December (OND) season and 2019’s June-August (JJA) and OND seasons, corresponding to the period when the highest water-levels were recorded in Lake Victoria. While land-use change in the study domain was observed, extended and unusually heavy June to December 2019 precipitation bore the greatest responsibility for the 2019/2020 high water-levels in Lake Victoria. The OND precipitation event of 2019 was a 1-in-52-year event compared to the 1961’s 1-in-693 years. Differences in return periods at various parts of the lake imply a high spatial climate variability within the lake itself. An analysis of the fraction of attributable risk (FAR) showed natural variability to have a greater influence on the JJA and OND precipitation patterns over Lake Victoria than human-induced climate change. However, variability over the land area of the study domain was mainly driven by human-induced climate change rather than natural variability, implying a unique climate system over Lake Victoria. Findings from the current study enhance the understanding of Lake Victoria’s water budget and motivate for further research to inform effective strategies on the planning and use of Lake Victoria’s water resources in a changing climate.

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The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6

Geoscientific Model Development ◽

10.5194/gmd-9-3461-2016 ◽

2016 ◽

Vol 9 (9) ◽

pp. 3461-3482 ◽

Cited By ~ 251

Author(s):

Brian C. O'Neill ◽

Claudia Tebaldi ◽

Detlef P. van Vuuren ◽

Veronika Eyring ◽

Pierre Friedlingstein ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

21St Century ◽

Integrated Assessment ◽

Climate Model ◽

Model Intercomparison ◽

Wide Range ◽

Scenario Model ◽

Intercomparison Project

Abstract. Projections of future climate change play a fundamental role in improving understanding of the climate system as well as characterizing societal risks and response options. The Scenario Model Intercomparison Project (ScenarioMIP) is the primary activity within Phase 6 of the Coupled Model Intercomparison Project (CMIP6) that will provide multi-model climate projections based on alternative scenarios of future emissions and land use changes produced with integrated assessment models. In this paper, we describe ScenarioMIP's objectives, experimental design, and its relation to other activities within CMIP6. The ScenarioMIP design is one component of a larger scenario process that aims to facilitate a wide range of integrated studies across the climate science, integrated assessment modeling, and impacts, adaptation, and vulnerability communities, and will form an important part of the evidence base in the forthcoming Intergovernmental Panel on Climate Change (IPCC) assessments. At the same time, it will provide the basis for investigating a number of targeted science and policy questions that are especially relevant to scenario-based analysis, including the role of specific forcings such as land use and aerosols, the effect of a peak and decline in forcing, the consequences of scenarios that limit warming to below 2 °C, the relative contributions to uncertainty from scenarios, climate models, and internal variability, and long-term climate system outcomes beyond the 21st century. To serve this wide range of scientific communities and address these questions, a design has been identified consisting of eight alternative 21st century scenarios plus one large initial condition ensemble and a set of long-term extensions, divided into two tiers defined by relative priority. Some of these scenarios will also provide a basis for variants planned to be run in other CMIP6-Endorsed MIPs to investigate questions related to specific forcings. Harmonized, spatially explicit emissions and land use scenarios generated with integrated assessment models will be provided to participating climate modeling groups by late 2016, with the climate model simulations run within the 2017–2018 time frame, and output from the climate model projections made available and analyses performed over the 2018–2020 period.

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Lake water level response to drought in a lake-rich region explained by lake and landscape characteristics

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2019-0270 ◽

2020 ◽

Vol 77 (11) ◽

pp. 1836-1845

Author(s):

K. Martin Perales ◽

Catherine L. Hein ◽

Noah R. Lottig ◽

M. Jake Vander Zanden

Keyword(s):

Climate Change ◽

Water Level ◽

Lake Water ◽

Water Levels ◽

Water Level Fluctuations ◽

Lake Area ◽

Lake Water Level ◽

Landscape Characteristics ◽

Lake Ecology ◽

Coarse Woody Habitat

Climate change is altering hydrologic regimes, with implications for lake water levels. While lakes within lake districts experience the same climate, lakes may exhibit differential climate vulnerability regarding water level response to drought. We took advantage of a recent drought (∼2005–2010) and estimated changes in lake area, water level, and shoreline position on 47 lakes in northern Wisconsin using high-resolution orthoimagery and hypsographic curves. We developed a model predicting water level response to drought to identify characteristics of the most vulnerable lakes in the region, which indicated that low-conductivity seepage lakes found high in the landscape, with little surrounding wetland and highly permeable soils, showed the greatest water level declines. To explore potential changes in the littoral zone, we estimated coarse woody habitat (CWH) loss during the drought and found that drainage lakes lost 0.8% CWH while seepage lakes were disproportionately impacted, with a mean loss of 40% CWH. Characterizing how lakes and lake districts respond to drought will further our understanding of how climate change may alter lake ecology via water level fluctuations.

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The Land Use Model Intercomparison Project (LUMIP) contribution to CMIP6: rationale and experimental design

Geoscientific Model Development ◽

10.5194/gmd-9-2973-2016 ◽

2016 ◽

Vol 9 (9) ◽

pp. 2973-2998 ◽

Cited By ~ 131

Author(s):

David M. Lawrence ◽

George C. Hurtt ◽

Almut Arneth ◽

Victor Brovkin ◽

Kate V. Calvin ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Experimental Design ◽

Land Cover ◽

Land Cover Change ◽

Land Management ◽

Model Intercomparison ◽

Land Use Model ◽

Intercomparison Project ◽

Process Level

Abstract. Human land-use activities have resulted in large changes to the Earth's surface, with resulting implications for climate. In the future, land-use activities are likely to expand and intensify further to meet growing demands for food, fiber, and energy. The Land Use Model Intercomparison Project (LUMIP) aims to further advance understanding of the impacts of land-use and land-cover change (LULCC) on climate, specifically addressing the following questions. (1) What are the effects of LULCC on climate and biogeochemical cycling (past–future)? (2) What are the impacts of land management on surface fluxes of carbon, water, and energy, and are there regional land-management strategies with the promise to help mitigate climate change? In addressing these questions, LUMIP will also address a range of more detailed science questions to get at process-level attribution, uncertainty, data requirements, and other related issues in more depth and sophistication than possible in a multi-model context to date. There will be particular focus on the separation and quantification of the effects on climate from LULCC relative to all forcings, separation of biogeochemical from biogeophysical effects of land use, the unique impacts of land-cover change vs. land-management change, modulation of land-use impact on climate by land–atmosphere coupling strength, and the extent to which impacts of enhanced CO2 concentrations on plant photosynthesis are modulated by past and future land use.LUMIP involves three major sets of science activities: (1) development of an updated and expanded historical and future land-use data set, (2) an experimental protocol for specific LUMIP experiments for CMIP6, and (3) definition of metrics and diagnostic protocols that quantify model performance, and related sensitivities, with respect to LULCC. In this paper, we describe LUMIP activity (2), i.e., the LUMIP simulations that will formally be part of CMIP6. These experiments are explicitly designed to be complementary to simulations requested in the CMIP6 DECK and historical simulations and other CMIP6 MIPs including ScenarioMIP, C4MIP, LS3MIP, and DAMIP. LUMIP includes a two-phase experimental design. Phase one features idealized coupled and land-only model simulations designed to advance process-level understanding of LULCC impacts on climate, as well as to quantify model sensitivity to potential land-cover and land-use change. Phase two experiments focus on quantification of the historic impact of land use and the potential for future land management decisions to aid in mitigation of climate change. This paper documents these simulations in detail, explains their rationale, outlines plans for analysis, and describes a new subgrid land-use tile data request for selected variables (reporting model output data separately for primary and secondary land, crops, pasture, and urban land-use types). It is essential that modeling groups participating in LUMIP adhere to the experimental design as closely as possible and clearly report how the model experiments were executed.

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The Land Use Model Intercomparison Project (LUMIP): Rationale and experimental design

10.5194/gmd-2016-76 ◽

2016 ◽

Cited By ~ 8

Author(s):

David M. Lawrence ◽

George C. Hurtt ◽

Almut Arneth ◽

Victor Brovkin ◽

Kate V. Calvin ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Experimental Design ◽

Land Cover ◽

Land Cover Change ◽

Land Management ◽

Model Intercomparison ◽

Land Use Model ◽

Intercomparison Project ◽

Process Level

Abstract. Human land-use activities have resulted in large to the Earth surface, with resulting implications for climate. In the future, land-use activities are likely to expand and intensify further to meet growing demands for food, fiber, and energy. The Land Use Model Intercomparison Project (LUMIP) aims to further advance understanding of the impacts of land-use and land-cover change (LULCC) on climate, specifically addressing the questions: (1) What are the effects of LULCC on climate and biogeochemical cycling (past–future)? (2) What are the impacts of land management on surface fluxes of carbon, water, and energy and are there regional land-management strategies with promise to help mitigate and/or adapt to climate change? In addressing these questions, LUMIP will also address a range of more detailed science questions to get at process-level attribution, uncertainty, data requirements, and other related issues in more depth and sophistication than possible in a multi-model context to date. There will be particular focus on the separation and quantification of the effects on climate from land-use change relative to fossil fuel emissions, separation of biogeochemical from biogeophysical effects of land-use, the unique impacts of land-cover change versus land management change, modulation of land-use impact on climate by land-atmosphere coupling strength, and the extent that impacts of enhanced CO2 concentrations on plant photosynthesis are modulated by past and future land use. LUMIP involves three major sets of science activities: (1) development of an updated and expanded historical and future land-use dataset, (2) an experimental protocol for specific LUMIP experiments for CMIP6, and (3) definition of metrics and diagnostic protocols that quantify model performance, and related sensitivities, with respect to-. In this paper, we describe the LUMIP simulations that will formally be part of CMIP6. These experiments are explicitly designed to be complementary to experiments from the CMIP core, ScenarioMIP, and C4MIP. LUMIP includes a two-phase experimental design. Phase one features idealized coupled and land-only model experiments designed to advance process-level understanding of LULCC impacts on climate, as well as to quantify model sensitivity to potential land-cover and land-use change. Phase two experiments focus on quantification of the historic impact of land use and the potential for future land management decisions to aid in mitigation of climate change. This paper documents these simulations in detail, explains their rationale, outlines plans for analysis, and describes a new subgrid land-use tile data request (primary and secondary land, crops, pasture, urban). It is essential that modeling groups participating in LUMIP adhere to the experimental design as closely as possible.

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Future Precipitation Patterns in the Lake Victoria Basin Using CMIP6 Projections

10.20944/preprints202107.0584.v1 ◽

2021 ◽

Author(s):

Obed M. Ogega ◽

Enrico Scoccimarro ◽

Hussen S. Endris ◽

Maurice Nyadawa ◽

James Mbugua ◽

...

Keyword(s):

Water Level ◽

Lake Victoria ◽

High Water ◽

Water Levels ◽

Water Level Fluctuations ◽

Mean Annual Precipitation ◽

Lake Victoria Basin ◽

Climate Services ◽

Precipitation Patterns ◽

Enhanced Production

In late/early 2019/2020, unprecedented high-water-levels were observed in Lake Victoria causing massive flooding in the low-lying lake-adjacent areas and disrupting human and natural systems in the Lake Victoria Basin (LVB). The high lake water-level coincided with unusually heavy and prolonged 2019 June to December precipitation in the LVB. The current study estimates future precipitation patterns over the LVB using HighResMIP and ScenarioMIP general circulation model (GCM) simulations from the 6th phase of the Coupled Model Intercomparison Project (CMIP6). Results show that HighResMIP and ScenarioMIP simulations can adequately reproduce LVB’s precipitation patterns – albeit with location-specific biases. Generally, the GCM simulations tend to over-estimate precipitation patterns over Lake Victoria while under-estimating precipitation patterns over the lake-adjacent areas. Projections show significant future precipitation changes over the LVB relative to the 1970-1999 baseline, with more pronounced changes over the lake than in lake-adjacent areas. Overall, mean annual precipitation is projected to increase by about 18% and 31% by the end of the century, under SSP2-4.5 and SSP5-8.5 scenarios, respectively. Additionally, mean daily precipitation intensity (SDII) is projected to increase by up-to 14% while the maximum 5-day precipitation values (RX5Day) increase by up-to 71% under the SSP5-8.5 scenario. Heavy precipitation events, represented by the width of the right tail distribution of precipitation (99p-90p), are projected to increase by 50% and 94% under SSP2-4.5 and SSP5-8.5, respectively. Given that direct precipitation accounts for about 80% of Lake Victoria’s water budget, the lake’s future water-level fluctuations are likely to be more rampant and unpredictable under the changing climate. Hence, enhanced production and use of climate services is recommended to minimize the risk posed by potentially high water-level fluctuations in Lake Victoria and, ultimately, enhance the socio-economic safety of communities in the LVB.

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AUTOMATIC WATER LEVEL MONITORING WITH IOT AND LPWAN

International Conference on Technics Technologies and Education ◽

10.15547/ictte.2019.02.041 ◽

2019 ◽

pp. 95-103

Author(s):

Krum Videnov ◽

Vanya Stoykova

Keyword(s):

Water Level ◽

Real Time ◽

Early Warning ◽

Water Sources ◽

Water Levels ◽

Water Level Fluctuations ◽

Level Monitoring ◽

Water Level Monitoring

Monitoring water levels of lakes, streams, rivers and other water basins is of essential importance and is a popular measurement for a number of different industries and organisations. Remote water level monitoring helps to provide an early warning feature by sending advance alerts when the water level is increased (reaches a certain threshold). The purpose of this report is to present an affordable solution for measuring water levels in water sources using IoT and LPWAN. The assembled system enables recording of water level fluctuations in real time and storing the collected data on a remote database through LoRaWAN for further processing and analysis.

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The effects of ENSO, climate change and human activities on the water level of Lake Toba, Indonesia: a critical literature review

Geoscience Letters ◽

10.1186/s40562-021-00191-x ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Hendri Irwandi ◽

Mohammad Syamsu Rosid ◽

Terry Mart

Keyword(s):

Climate Change ◽

Water Level ◽

Human Activities ◽

Southern Oscillation ◽

Climatic Conditions ◽

Water Levels ◽

Dominant Factor ◽

Climate Projections ◽

Continuous Increase ◽

The Future

AbstractThis research quantitatively and qualitatively analyzes the factors responsible for the water level variations in Lake Toba, North Sumatra Province, Indonesia. According to several studies carried out from 1993 to 2020, changes in the water level were associated with climate variability, climate change, and human activities. Furthermore, these studies stated that reduced rainfall during the rainy season due to the El Niño Southern Oscillation (ENSO) and the continuous increase in the maximum and average temperatures were some of the effects of climate change in the Lake Toba catchment area. Additionally, human interventions such as industrial activities, population growth, and damage to the surrounding environment of the Lake Toba watershed had significant impacts in terms of decreasing the water level. However, these studies were unable to determine the factor that had the most significant effect, although studies on other lakes worldwide have shown these factors are the main causes of fluctuations or decreases in water levels. A simulation study of Lake Toba's water balance showed the possibility of having a water surplus until the mid-twenty-first century. The input discharge was predicted to be greater than the output; therefore, Lake Toba could be optimized without affecting the future water level. However, the climate projections depicted a different situation, with scenarios predicting the possibility of extreme climate anomalies, demonstrating drier climatic conditions in the future. This review concludes that it is necessary to conduct an in-depth, comprehensive, and systematic study to identify the most dominant factor among the three that is causing the decrease in the Lake Toba water level and to describe the future projected water level.

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The effect of water level on lateral movements of fish between river and off-channel habitats and implications for management

Marine and Freshwater Research ◽

10.1071/mf08246 ◽

2010 ◽

Vol 61 (3) ◽

pp. 271 ◽

Cited By ~ 37

Author(s):

Jarod Lyon ◽

Ivor Stuart ◽

David Ramsey ◽

Justin O'Mahony

Keyword(s):

Water Level ◽

Fish Community ◽

Life History Strategy ◽

Water Levels ◽

Water Level Fluctuations ◽

Main River Channel ◽

Murray River ◽

Wetland Biodiversity ◽

Eastern Australia ◽

Riverine Wetland

Off-channel habitats, such as wetlands and backwaters, are important for the productivity of river systems and for many species of native fish. This study aimed to investigate the fish community, timing and cues that stimulated movement to and from off-channel habitats in the highly regulated Lake Hume to Lake Mulwala reach of the Murray River, south-eastern Australia. In 2004–05, 193 712 fish were collected moving bi-directionally between a 50-km section of the Murray River and several off-channel habitats. Lateral fish movements approximated water level fluctuations. Generally as water levels rose, fish left the main river channel and moved into newly flooded off-channel habitats; there was bi-directional movement as water levels peaked; on falling levels fish moved back to the permanent riverine habitats. Fish previously classified as ‘wetland specialists’, such as carp gudgeons (Hypseleotris spp.), have a more flexible movement and life-history strategy including riverine habitation. The high degree of lateral movement indicates the importance of habitat connectivity for the small-bodied fish community. Wetlands adjacent to the Murray River are becoming increasingly regulated by small weirs and ensuring lateral fish movement will be important in maintaining riverine-wetland biodiversity.

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Regulation of Vegetation and Evapotranspiration by Water Level Fluctuation in Shallow Lakes

Water ◽

10.3390/w13192651 ◽

2021 ◽

Vol 13 (19) ◽

pp. 2651

Author(s):

Qiang Liu ◽

Liqiao Liang ◽

Xiaomin Yuan ◽

Sirui Yan ◽

Miao Li ◽

...

Keyword(s):

Water Level ◽

Open Water ◽

Water Area ◽

Water Level Fluctuation ◽

Water Levels ◽

Water Level Fluctuations ◽

Water Evaporation ◽

Level Fluctuation ◽

Open Water Area ◽

Annual Scale

Water level fluctuations play a critical role in regulating vegetation distribution, composition, cover and richness, which ultimately affect evapotranspiration. In this study, we first explore water level fluctuations and associated impacts on vegetation, after which we assess evapotranspiration (ET) under different water levels. The normalized difference vegetation index (NDVI) was used to estimate the fractional vegetation cover (Fv), while topography- and vegetation-based surface-energy partitioning algorithms (TVET model) and potential evaporation (Ev) were used to calculate ET and water evaporation (Ep). Results show that: (1) water levels were dramatically affected by the combined effect of ecological water transfer and climate change and exhibited significant decreasing trends with a slope of −0.011 m a−2; and (2) as predicted, there was a correlation between water level fluctuation at an annual scale with Phragmites australis (P. australis) cover and open-water area. Water levels also had a controlling effect on Fv values, an increase in annual water levels first increasing and then decreasing Fv. However, a negative correlation was found between Fv values and water levels during initial plant growth stages. (iii) ET, which varied under different water levels at an annual scale, showed different partition into transpiration from P. australis and evaporation from open-water area and soil with alterations between vegetation and open water. All findings indicated that water level fluctuations controlled biological and ecological processes, and their structural and functional characteristics. This study consequently recommends that specifically-focused ecological water regulations (e.g., duration, timing, frequency) should be enacted to maintain the integrity of wetland ecosystems for wetland restoration.

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Determination of diurnal water level fluctuations in headwaters

Hydrology Research ◽

10.2166/nh.2016.039 ◽

2016 ◽

Vol 47 (4) ◽

pp. 888-901 ◽

Cited By ~ 1

Author(s):

Marek Marciniak ◽

Anna Szczucińska

Keyword(s):

Water Temperature ◽

Water Level ◽

Air Temperature ◽

Hyporheic Zone ◽

Water Pressure ◽

Water Levels ◽

Water Level Fluctuations ◽

Diurnal Changes ◽

Atmospheric Conditions ◽

Diurnal Fluctuations

The aim of this paper is to study diurnal fluctuations of the water level in streams draining headwaters and to identify the controlling factors. The fieldwork was carried out in the Gryżynka River catchment, western Poland. The water levels of three streams draining into the headwaters via a group of springs were monitored in the years 2011–2014. Changes in the water pressure and water temperature were recorded by automatic sensors – Schlumberger MiniDiver type. Simultaneously, Barodiver type sensors were used to record air temperature and atmospheric pressure, as it was necessary to adjust the data collected by the MiniDivers calculate the water level. The results showed that diurnal fluctuations in water level of the streams ranged from 2 to 4 cm (approximately 10% of total water depth) and were well correlated with the changes in evapotranspiration as well as air temperature. The observed water level fluctuations likely have resulted from processes occurring in the headwaters. Good correlation with atmospheric conditions indicates control by daily variations of the local climate. However, the relationship with water temperature suggests that fluctuations are also caused by changes in the temperature-dependent water viscosity and, consequently, by diurnal changes in the hydraulic conductivity of the hyporheic zone.

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