Modelling the impact of future socio-economic and climate change scenarios on river microbial water quality

In this study, we investigated the impact of climate change on streamflow and water quality (TSS, T-N, and T-P loads) in the upper Dong Nai River Basin using the Soil and Water Assessment Tool (SWAT) hydrological model. The calibration and validation results indicated that the SWAT model is a reasonable tool for simulating streamflow and water quality for this basin. Based on the well-calibrated SWAT model, the responses of streamflow, sediment load, and nutrient load to climate change were simulated. Climate change scenarios (RCP 4.5 and RCP 8.5) were developed from five GCM simulations (CanESM2, CNRM-CM5, HadGEM2-AO, IPSL-CM5A-LR, and MPI-ESM-MR) using the delta change method. The results indicated that climate in the study area would become warmer and wetter in the future. Climate change leads to increases in streamflow, sediment load, T-N load, and T-P load. Besides that, the impacts of climate change would exacerbate serious problems related to water shortage in the dry season and soil erosion and degradation in the wet season. In addition, it is indicated that changes in sediment yield and nutrient load due to climate change are larger than the corresponding changes in streamflow.

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A Practical Approach to Developing Climate Change Scenarios for Water Quality Models

Journal of Hydrometeorology ◽

10.1175/jhm-d-18-0213.1 ◽

2019 ◽

Vol 20 (6) ◽

pp. 1197-1211 ◽

Cited By ~ 4

Author(s):

Rakesh K. Gelda ◽

Rajith Mukundan ◽

Emmet M. Owens ◽

John T. Abatzoglou

Keyword(s):

Climate Change ◽

Water Quality ◽

New York ◽

Wind Speed ◽

Solar Radiation ◽

Climate Change Scenarios ◽

Quality Models ◽

Hourly Data ◽

Water Quality Models ◽

The Impact

Abstract Climate model output is often downscaled to grids of moderately high spatial resolution (~4–6-km grid cells). Such projections have been used in numerous hydrological impact assessment studies at watershed scales. However, relatively few studies have been conducted to assess the impact of climate change on the hydrodynamics and water quality in lakes and reservoirs. A potential barrier to such assessments is the need for meteorological variables at subdaily time scales that are downscaled to in situ observations to which lake and reservoir water quality models have been calibrated and validated. In this study, we describe a generalizable procedure that utilizes gridded downscaled data; applies a secondary bias-correction procedure using equidistance quantile mapping to map projections to station-based observations; and implements temporal disaggregation models to generate point-scale hourly air and dewpoint temperature, wind speed, and solar radiation for use in water quality models. The proposed approach is demonstrated for six locations within New York State: four within watersheds of the New York City water supply system and two at nearby National Weather Service stations. Disaggregation models developed using observations reproduced hourly data well at all locations, with Nash–Sutcliffe efficiency greater than 0.9 for air temperature and dewpoint, 0.4–0.6 for wind speed, and 0.7–0.9 for solar radiation.

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Watershed-Scale Surface Runoff and Water Quality Response to Climate Change, Urbanization, and Implementation of LIDs

10.20944/preprints201901.0184.v1 ◽

2019 ◽

Author(s):

Mohammad Nazari-Sharabian ◽

Moses Karakouzian ◽

Sajjad Ahmad

Keyword(s):

Climate Change ◽

Water Quality ◽

Climate Change Impacts ◽

Climate Change Scenarios ◽

Storm Water Management Model ◽

Quality Properties ◽

Pollutant Loads ◽

Impact Of Urbanization ◽

Quality Response ◽

The Impact

The Storm Water Management Model (SWMM) was used to evaluate the impact of urbanization, climate change, and implementation of Low Impact Developments (LIDs) at the Mahabad Dam watershed, Iran. Several scenarios of urbanization, with and without climate change impacts, in different locations were defined, including near outlet, middle, far end, and whole watershed. Climate change was considered to change the intensity of rainfall and increase evaporation. Vegetative swales were implemented as LIDs to evaluate their applicability to reduce pollutant loads. Digital Elevation Model (DEM) of the area was input into ArcGIS, and the watershed was delineated using the ArcSWAT extension to identify topographic features. Water quality properties were defined in the software, and each scenario was run for a twelve-hour simulation. The results indicated that urbanization affects the imperviousness of sub-catchments, and location of urbanization affects the amount and timing of runoff and pollutant yields. Fifty-percent urbanization near the watershed outlet resulted in 23.1% and 27.4% increases in runoff and pollutant loads, respectively. Fifty-percent urbanization in the middle resulted in 28.8% and 35.4% increases in runoff and pollutant loads; and, at the far end, 23.1% and 3.9% increases in runoff and pollutant loads were the result; Fifty-percent urbanizing the whole watershed gave 58.6% and 66.3% increases in runoff and pollutant loads, respectively; Under climate change scenarios (higher intensity, shorter duration rainfall) peaks occurred earlier. Moreover, results showed LIDs decreased pollution loads up to 25%.

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Impacts of climate change scenarios on dissolved oxygen in the River Thames, UK

Hydrology Research ◽

10.2166/nh.2009.096 ◽

2009 ◽

Vol 40 (2-3) ◽

pp. 138-152 ◽

Cited By ~ 30

Author(s):

B. A. Cox ◽

P. G. Whitehead

Keyword(s):

Climate Change ◽

Water Quality ◽

Dissolved Oxygen ◽

Probability Distributions ◽

Stochastic Modelling ◽

River System ◽

Treated Wastewater ◽

Climate Change Scenarios ◽

Quality Model ◽

The Impact

A water quality model is used to assess the impact of possible climate change on dissolved oxygen (DO) in the Thames. The Thames catchment is densely populated and, typically, many pressures are anthropogenic. However, that same population also relies on the river for potable water supply and as a disposal route for treated wastewater. Thus, future water quality will be highly dependent on future activity. Dynamic and stochastic modelling has been used to assess the likely impacts on DO dynamics along the river system and the probability distributions associated with future variability. The modelling predictions indicate that warmer river temperatures and drought act to reduce dissolved oxygen concentrations in lowland river systems.

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THE IMPACT OF CLIMATE CHANGE ON WATER QUALITY IN THE CORDILLERA BLANCA, PERU

10.1130/abs/2018am-323092 ◽

2018 ◽

Author(s):

Carmen Longo ◽

◽

Elizabeth Balgord ◽

Timothy F. Diedesch ◽

John All

Keyword(s):

Climate Change ◽

Water Quality ◽

Cordillera Blanca ◽

Impact Of Climate Change ◽

The Impact

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Urban Geometry Optimization to Mitigate Climate Change: Towards Energy-Efficient Buildings

Sustainability ◽

10.3390/su13010027 ◽

2020 ◽

Vol 13 (1) ◽

pp. 27

Author(s):

Hatem Mahmoud ◽

Ayman Ragab

Keyword(s):

Climate Change ◽

Heat Stress ◽

Thermal Efficiency ◽

Energy Demand ◽

Building Blocks ◽

Climate Projections ◽

Climate Change Scenarios ◽

Urban Geometry ◽

Outdoor Spaces ◽

The Impact

The density of building blocks and insufficient greenery in cities tend to contribute dramatically not only to increased heat stress in the built environment but also to higher energy demand for cooling. Urban planners should, therefore, be conscious of their responsibility to reduce energy usage of buildings along with improving outdoor thermal efficiency. This study examines the impact of numerous proposed urban geometry cases on the thermal efficiency of outer spaces as well as the energy consumption of adjacent buildings under various climate change scenarios as representative concentration pathways (RCP) 4.5 and 8.5 climate projections for New Aswan city in 2035. The investigation was performed at one of the most underutilized outdoor spaces on the new campus of Aswan University in New Aswan city. The potential reduction of heat stress was investigated so as to improve the thermal comfort of the investigated outdoor spaces, as well as energy savings based on the proposed strategies. Accordingly, the most appropriate scenario to be adopted to cope with the inevitable climate change was identified. The proposed scenarios were divided into four categories of parameters. In the first category, shelters partially (25–50% and 75%) covering the streets were used. The second category proposed dividing the space parallel or perpendicular to the existing buildings. The third category was a hybrid scenario of the first and second categories. In the fourth category, a green cover of grass was added. A coupling evaluation was applied utilizing ENVI-met v4.2 and Design-Builder v4.5 to measure and improve the thermal efficiency of the outdoor space and reduce the cooling energy. The results demonstrated that it is better to cover outdoor spaces with 50% of the overall area than transform outdoor spaces into canyons.

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Potential Impacts of Future Climate Change Scenarios on Ground Subsidence

Water ◽

10.3390/w12010219 ◽

2020 ◽

Vol 12 (1) ◽

pp. 219 ◽

Cited By ~ 2

Author(s):

Antonio-Juan Collados-Lara ◽

David Pulido-Velazquez ◽

Rosa María Mateos ◽

Pablo Ezquerro

Keyword(s):

Climate Change ◽

Land Subsidence ◽

Ground Subsidence ◽

Lower Percentage ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Fine Grained ◽

Fine Grained Material ◽

The Impact

In this work, we developed a new method to assess the impact of climate change (CC) scenarios on land subsidence related to groundwater level depletion in detrital aquifers. The main goal of this work was to propose a parsimonious approach that could be applied for any case study. We also evaluated the methodology in a case study, the Vega de Granada aquifer (southern Spain). Historical subsidence rates were estimated using remote sensing techniques (differential interferometric synthetic aperture radar, DInSAR). Local CC scenarios were generated by applying a bias correction approach. An equifeasible ensemble of the generated projections from different climatic models was also proposed. A simple water balance approach was applied to assess CC impacts on lumped global drawdowns due to future potential rainfall recharge and pumping. CC impacts were propagated to drawdowns within piezometers by applying the global delta change observed with the lumped assessment. Regression models were employed to estimate the impacts of these drawdowns in terms of land subsidence, as well as to analyze the influence of the fine-grained material in the aquifer. The results showed that a more linear behavior was observed for the cases with lower percentage of fine-grained material. The mean increase of the maximum subsidence rates in the considered wells for the future horizon (2016–2045) and the Representative Concentration Pathway (RCP) scenario 8.5 was 54%. The main advantage of the proposed method is its applicability in cases with limited information. It is also appropriate for the study of wide areas to identify potential hot spots where more exhaustive analyses should be performed. The method will allow sustainable adaptation strategies in vulnerable areas during drought-critical periods to be assessed.

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Impact of an accelerated melting of Greenland on malaria distribution over Africa

Nature Communications ◽

10.1038/s41467-021-24134-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Alizée Chemison ◽

Gilles Ramstein ◽

Adrian M. Tompkins ◽

Dimitri Defrance ◽

Guigone Camus ◽

...

Keyword(s):

Climate Change ◽

Malaria Transmission ◽

Ice Sheet ◽

Transmission Risk ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Climate Change Risk ◽

System A ◽

Climate Simulations ◽

The Impact

AbstractStudies about the impact of future climate change on diseases have mostly focused on standard Representative Concentration Pathway climate change scenarios. These scenarios do not account for the non-linear dynamics of the climate system. A rapid ice-sheet melting could occur, impacting climate and consequently societies. Here, we investigate the additional impact of a rapid ice-sheet melting of Greenland on climate and malaria transmission in Africa using several malaria models driven by Institute Pierre Simon Laplace climate simulations. Results reveal that our melting scenario could moderate the simulated increase in malaria risk over East Africa, due to cooling and drying effects, cause a largest decrease in malaria transmission risk over West Africa and drive malaria emergence in southern Africa associated with a significant southward shift of the African rain-belt. We argue that the effect of such ice-sheet melting should be investigated further in future public health and agriculture climate change risk assessments.

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Selection of models to describe the temperature-dependent development of Neoleucinodes elegantalis (Lepidoptera: Crambidae) and its application to predict the species voltinism under future climate conditions

Bulletin of Entomological Research ◽

10.1017/s0007485321000195 ◽

2021 ◽

pp. 1-9

Author(s):

Hevellyn Talissa dos Santos ◽

Cesar Augusto Marchioro

Keyword(s):

Climate Change ◽

Linear Model ◽

Future Climate ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Temperature Dependent ◽

Dependent Development ◽

Degree Day ◽

Non Linear ◽

The Impact

Abstract The small tomato borer, Neoleucinodes elegantalis (Guenée, 1854) is a multivoltine pest of tomato and other cultivated solanaceous plants. The knowledge on how N. elegantalis respond to temperature may help in the development of pest management strategies, and in the understanding of the effects of climate change on its voltinism. In this context, this study aimed to select models to describe the temperature-dependent development rate of N. elegantalis and apply the best models to evaluate the impacts of climate change on pest voltinism. Voltinism was estimated with the best fit non-linear model and the degree-day approach using future climate change scenarios representing intermediary and high greenhouse gas emission rates. Two out of the six models assessed showed a good fit to the observed data and accurately estimated the thermal thresholds of N. elegantalis. The degree-day and the non-linear model estimated more generations in the warmer regions and fewer generations in the colder areas, but differences of up to 41% between models were recorded mainly in the warmer regions. In general, both models predicted an increase in the voltinism of N. elegantalis in most of the study area, and this increase was more pronounced in the scenarios with high emission of greenhouse gases. The mathematical model (74.8%) and the location (9.8%) were the factors that mostly contributed to the observed variation in pest voltinism. Our findings highlight the impact of climate change on the voltinism of N. elegantalis and indicate that an increase in its population growth is expected in most regions of the study area.

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Irrigation water requirements for seed corn and coffee under potential climate change scenarios

Journal of Water and Climate Change ◽

10.2166/wcc.2015.025 ◽

2015 ◽

Vol 7 (1) ◽

pp. 39-51 ◽

Cited By ~ 9

Author(s):

Ali Fares ◽

Ripendra Awal ◽

Samira Fares ◽

Alton B. Johnson ◽

Hector Valenzuela

Keyword(s):

Climate Change ◽

Irrigation Water ◽

Co2 Emission ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Deep Percolation ◽

Canopy Interception ◽

Water Requirements ◽

Seed Corn ◽

The Impact

The impact of potential future climate change scenarios on the irrigation water requirements (IRRs) of two major agricultural crops (coffee and seed corn) in Hawai'i was studied using the Irrigation Management System (IManSys) model. In addition to IRRs calculations, IManSys calculates runoff, deep percolation, canopy interception, and effective rainfall based on plant growth parameters, site specific soil hydrological properties, irrigation system efficiency, and long-term daily weather data. Irrigation water requirements of two crops were simulated using historical climate data and different levels of atmospheric CO2 (330, 550, 710 and 970 ppm), temperature (+1.1 and +6.4 °C) and precipitation (±5, ±10 and ±20%) chosen based on the Intergovernmental Panel on Climate Change (IPCC) AR4 projections under reference, B1, A1B1 and A1F1 emission scenarios. IRRs decreased as CO2 emission increased. The average percentage decrease in IRRs for seed corn is higher than that of coffee. However, runoff, rain canopy interception, and deep percolation below the root zone increased as precipitation increased. Canopy interception and drainage increased with increased CO2 emission. Evapotranspiration responded positively to air temperature rise, and as a result, IRRs increased as well. Further studies using crop models will predict crop yield responses to these different irrigation scenarios.

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