Download or read book Numerical Simulation of the Effect of Land Cover and Climate Changes on Hydrologic Regimes in an Inland Pacific Northwest Watershed written by Enhao Du and published by . This book was released on 2010 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spatial and temporal patterns of canopy alterations suggest that completely clear-cutting the entire watershed would increase runoff by 73% and 5 th percentile streamflows by 66%. The hydrologic effects were less pronounced relative to the degree of canopy removal in a partial-cut scenario where 50% of the canopy was removed across the entire watershed. Streamflow regimes approached baseline conditions after approximately 25 years of forest regeneration, and indicated almost complete recovery after 50 years. Gradually patch-cutting 5% of the watershed area every 6 years caused water yield to increase by 17% and remain very stable after 20 years. Hydrologic responses to various spatial harvest patterns were relatively similar.

Download or read book Estimating Postfire Water Production in the Pacific Northwest written by Donald F. Potts and published by . This book was released on 1989 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two hydrologic models were adapted to estimate postfire changer in water yield in Pacific Northwest watersheds. The WRENSS version of the simulation model PROSPER is used for hydrologic regimes dominated by rainfall: it calculates water available for streamflow onthe basis of seasonal precipitation and leaf area index. The WRENSS version of the simulation model WATBAL is used for hydrologic regimes dominated by snowfall; it calculates water available for streamflow based on seasonal precipitation, energy aspect and cover density. The PROSPER and WATBAL models estimate large postfire increases in water available for streamflow only for fires that have removed more than 50 percent of the leaf area are cover density, respectively. Guidelines for selecting appropriate models, and tables and figures for calculating postfire water yield are presented. This simulation approach should be useful for estimating long-term effects of fire on water production within the framework of land management planning.

Download or read book Simulating the Hydrologic Impacts of Land Cover and Climate Changes Under a Semi arid Environment written by Heyin Chen and published by . This book was released on 2013 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Changes in climate and land cover are two principal and independant variables affecting hydrologic conditions in a watershed. This paper presents a cell-based model and the hydrologic simulation for semi-arid Lower Virgin River (LVR) watershed located upstream of Lake Mead, Nevada, the largest man-made reservoir in the United States. The model is developed by considering: (a) direct runoff simulation based on the Soil Conservation Service Curve Number (SCS-CN) method; (b) surplus runoff simulation based on the Thornthwaite's water balance theory; and (c) land cover conditions based on the use of surface temperature (Ts) and Normalized Difference Vegetation Index (NDVI). It is found that this cell-based model provides acceptable predictions of total surface runoff and river discharge in the semi-arid region. Using the simulated land cover changes and the IPCC climate projections, quantitative model simulations point to climate change as the dominant factor in regulating surface stream flow and land cover changes as a secondary factor marginally enhancing the hydrologic change. The combined effect will very likely lead to large increases and decreases of stream flow into Lake Meade during the summer and winter months, respectively, an global change impact that deserves attention in climate change adaptation planning.

Download or read book Effects of Land cover Change on Streamflow written by Peter James Dennedy-Frank and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Globally, more than 700 million people live in watersheds with a degraded ability to provide hydrologic ecosystem (hydro-eco) services, such as improved water yield and moderation of peak and dry-season river flows. Restoring pre-development land cover to provide hydro-eco services has become a major driver of conservation. This dissertation investigates the hydrologic response to land-cover change in high-resolution hydrologic models of 32 watersheds spanning six continents and diverse climate zones. The watershed site models are used to explore streamflow changes for scenarios of land-cover restoration to a pre-development state, as well as land-cover development to agricultural or urban conditions. The site models are used to simulate land-cover change of 10% of watershed area, which is larger than the area typically selected for hydro-eco service investment. On average the magnitude of annual average water yield, low flow, and high flow are reduced 1-3% under restoration. The magnitude is similar but the direction reversed for development to agricultural or urban conditions. Focusing on restoration, results show that groups of watersheds have similar streamflow response characteristics to land cover-change despite the limited response magnitude. The groups are identified using a graph-connectedness approach based on the sign correlation of changes in 26 streamflow index values. Watersheds fall into three clusters characterized by their hydrologic responses to land-cover change: 1) low-flow intensifying, 2) high-flow intensifying, and 3) high-flow enhancing. Non-parametric hypothesis testing is used to identify which particular streamflow indices, watershed features, and pre-restoration flow features are characteristic of watersheds in the respective clusters. Under restoration, sites in the low-flow intensifying cluster exhibit an increase in low flow and a decrease in high flow. Sites in the high-flow intensifying cluster show high flow increases (relative to each site's median flow) and low flow decreases. The high-flow enhancing cluster behaves like the high-flow intensifying cluster, but has smaller reductions in low flows. Soil characteristics in the sites are distinct across clusters. Watersheds with smaller soil depths and available soil water content fall into the low-flow intensifying cluster, and these soil characteristics are statistically different from those of sites in the high-flow enhancing and intensifying clusters. After restoration, the low-flow intensifying watersheds typically exhibit greater infiltration and shift water to the low-flow regime. This flowvi regulating behavior is a desired effect of watershed restoration. In contrast, high-flow intensifying watersheds exhibit increased transpiration that reduces low flow. Such behavior is detrimental to regions with limited water availability. This study uses local hydrologic site models in a broad range of conditions to better understand how landcover changes affect hydrologic response and under what conditions such changes might enhance hydro-eco services. Results contribute useful guidance about the generally limited effects of land-cover change on water yield. This work also provides useful understanding about key watershed characteristics that affect streamflow responses to restoration.

Download or read book Impacts of Land Cover and Climate Change on Water Resources in Suasco River Watershed written by Ammara Talib and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT IMPACTS OF LAND COVER AND CLIMATE CHANGE ON WATER RESOURCES IN SUASCO RIVER WATERSHED September 2015 AMMARA TALIB, BS., PUNJAB UNIVERSITY LAHORE MS., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Tim Randhir Hydrological balance and biogeochemical processes in watershed are significantly influenced by changes in land use land cover (LULC) and climate change. Those changes can influence interception, evapotranspiration (ET), infiltration, soil moisture, water balance and biogeochemical cycling of carbon, nitrogen and other elements at regional to global scales. The impacts of these hydrological disturbances are generally reflected in form of increasing runoff rate and volume, more intense and frequent floods, decreasing groundwater recharge and base flow, elevated levels of sediments and increase in concentration of nutrients in both streams and shallow groundwater. Water quality of Sudbury, Assabet and Concord (SuAsCo) watershed in Massachusetts is also compromised because of influx of runoff, sediments and nutrients. There is a crucial need to evaluate the synergistic effects of LULC change and climate change on the water quality and water quantity in a watershed system. A watershed simulation model is used to simulate hydrologic processes and water quality changes in sediment loads, total nitrogen (TN), and total phosphorus (TP). The model is calibrated and validated with field-measured data. Climatic scenarios are represented by downscaled regional projections from Global Climate Model (GCM) models and regional built out scenarios of LULC are used to assess the impacts of projected LULC and climate change on water quality and water quantity. Simultaneous changes in LULC and climate significantly affect the water resources in the SuAsCo River watershed. Change in climate increased ET (4.7 %) because of high temperature, but independent change in land cover reduced ET (6.5%) because of less available vegetation. Combined change in land cover and climate reduced ET (2.1%) overall, which indicates that land cover change has significant impact on ET. Change in climate increased total run off (6%) and this increase is more significant as compared to 2.7 % increase in total runoff caused by land cover change. Change in land cover increased surface runoff more significantly (69.2%) than 7.9 % increase caused by climate change. Combined change in land cover and climate further increased the average storm peak volume (12.8 percent) because of high precipitation and impervious area in future. There is a potential for reducing runoff, sediments and nutrients loads by using conservation policies and adaptation strategies. This research provides valuable information about the dynamics of watershed system, as well as the complex processes that impair water resources.

Download or read book The Effects of Climate Change and Urbanization on the Runoff of the Rock Creek Basin written by and published by . This book was released on 2008 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate changes brought on by global warming are expected to have a significant affect on the Pacific Northwest hydrology during the 21st Century. Current research anticipates higher mean annual temperatures and an intensification of the hydrological cycle. This is of particular concern for highly urbanized basins, which are considered more vulnerable to changes in climate. Because the majority of previous studies have addressed the influences of either climate or urban land cover changes on runoff, there is a lack of research investigating the combined effect of these factors. The Rock Creek basin (RCB), located in the Portland, OR, metropolitan area, has been experiencing rapid urban growth throughout the last 30 years, making it an ideal study area for assessing the affect of climate and land cover changes on runoff. Methods for this assessment include using a combination of climate change and land cover change scenarios for 2040 with the semi distributed AVSWAT-X (Arc View Soil and Water Assessment Tool) hydrological model to determine changes in mean runoff depths at the monthly, seasonal, and annual scales. Statistically downscaled climate change results from the ECHAM5 general circulation model (GCM) found that the region would experience an increase of 1.2°C in the average annual temperature and a 6% increase in average annual precipitation between 2030 and 2059. The model results revealed an amplification of runoff from either climate or urbanization. Projected climate change plus low-density, sprawled urban development for 2040 produced the greatest change to mean annual runoff depth (+5.5%), while climate change plus higher-density urban development for 2040 resulted in the smallest change (+5.3%), when compared to the climate and land cover of 2001. The results of this study support the hypothesis that the combination of both climate change and urbanization would amplify the runoff from the RCB during the 21st Century. This has significant implications for water resource managers attempting to implement adaptive water resource policies to future changes resulting from climate and urbanization.

Download or read book Climate Change in the Northwest written by Meghan M. Dalton and published by NCA Regional Input Reports. This book was released on 2013-12-19 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate Change in the Northwest: Implications for Our Landscapes, Waters, and Communities is aimed at assessing the state of knowledge about key climate impacts and consequences to various sectors and communities in the northwest United States. It draws on a wealth of peer-reviewed literature, earlier state-level assessment reports conducted for Washington (2009) and Oregon (2010), as well as a risk-framing workshop. As an assessment, it aims to be representative (though not exhaustive) of the key climate change issues as reflected in the growing body of Northwest climate change science, impacts, and adaptation literature now available. This report will serve as an updated resource for scientists, stakeholders, decision makers, students, and community members interested in understanding and preparing for climate change impacts on Oregon, Washington, and Idaho. This more detailed, foundational report is intended to support the key findings presented in the Northwest chapter of the Third National Climate Assessment.

Download or read book Climate Change and Land Use Cover Change Impacts on Watershed Hydrology Nutrient Dynamics a Case Study in Missisquoi River Watershed written by Linyuan Shang and published by . This book was released on 2019 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Watershed regulation of water, carbon and nutrient dynamics support food, drinking water and human development. Projected climate changes and land use/cover change (LUCC) have been identified as drivers of watershed nutrient and hydrological processes and are likely to happen jointly in the future decades. Studying climate change and LUCC impacts on watersheds' streamflow and nutrients dynamics is therefore essential for future watershed management. This research aimed to unveil how climate change and LUCC affect water and nutrient dynamics in the Missisquoi River watershed, Vermont. We used 12 scenarios of future climate data (2021 - 2050) generated by three GCMs (ccsm4, mri-cgcm3, and gfdl-esm2m) under four Representative Concentration Pathways (RCPs). For LUCC, we used three different scenarios generated by the Interactive Land Use Transition Agent-Based Model (ILUTABM). The three LUCC scenarios were Business As Usual (BAU), Prefer Forest (proForest), and Prefer Agriculture (proAg). New land use maps were generated every 10 years for the period of 2021 - 2050. Combining each climate change and LUCC scenario resulted in 36 scenarios that were used to drive Regional Hydro-Ecologic Simulation System (RHESSys) ecohydrological model. In chapter 3, we used RHESSys to study streamflow. We found climate was the main driver for streamflow because climate change directly controlled the system water input. For streamflow, climate change scenarios had larger impacts than LUCC, different LUCCs under the same climate change scenario had similar annual flow patterns. In chapter 4, we used RHESSys to study streamflow NO3-N and NH4-N load. Because fertilizer application is the major source for nitrogen export, LUCC had larger impacts; watersheds with more agricultural land had larger nitrogen loads. In chapter 5, we developed RHESSys-P by coupling the DayCent phosphorus module with RHESSys to study climate change and LUCC impacts on Dissolved Phosphorus (DP) load. RHESSys-P was calibrated with observed DP data for 2002 - 2004 and validated with data for 2009 - 2010. In both calibration and validation periods, simulated DP basically captured patterns of observed DP. In the validation period, the R2 of simulated vs observed DP was 0.788. Future projection results indicated BAU and proForest annual loads were around 4.0 x 104 kg under all climate change scenarios; proAg annual loads increased from around 4.0 x 104 kg in 2021 to 1.6 x 105 kg in 2050 under all climate change scenarios. The results showed LUCC was the dominant factor for dissolved phosphorus loading. Overall, our results suggest that, while climate drives streamflow, N and P fluxes are largely driven by land use and management decisions. To balance human development and environmental quality, BAU is a feasible future development strategy.

Download or read book Assessing the Impacts of Climate Change on Fluvial Processes written by Robert Baidoc and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Watershed models are an important tool in regional planning and conservation efforts. They can provide valuable insight into the potential impacts of different land use changes and future climate change scenarios on water resources, which can lead to better, more informed decision making. Climate impacts, in particular, add a new level of uncertainty with regard to freshwater supplies as the hydrological cycle is intimately linked with changes in atmospheric temperatures. The main objective of this study is to investigate the extent of long-term climate change on streamflow and stream temperature within an agriculturally defined watershed in Northern Ontario. For this purpose, the Soil and Water Assessment Tool (SWAT) model was utilized to provide a better understanding of how hydrological processes in the Slate River Watershed will alter in response to long-term climate change scenarios. The SWAT model is a distributed/semi-distributed physically-based continuous model, developed by the USDA for the management of agricultural watersheds, and is currently one of the most popular watershed-based models used in climate change analysis of snowmelt dominated watersheds. Historic flow data was compared to a discharge model that reflected four climate models driven by SRES A1B and A2 through the middle and end of the century. Hydrology modelling was enhanced with stream temperature analysis to gain a comprehensive understanding of the extent of changing climate regimes on the Slate River. A linear regression approach representing a positive relationship between stream temperature and air temperature was used to determine the thermal classification of the Slate River. Our results indicated that the Slate River was well within the warm-water character regime. Unusual high stream temperatures were recorded at mid- August; these were accompanied by low water levels and a lack of riparian vegetative cover at the recording site, providing a possible explanation for such temperature anomalies. The results of the flow discharge modelling supported our hypothesis that tributaries within our ecosystem would experience increasing water stress in a warming climate as the average total discharge from the Slate River decreased in both climate scenarios at the middle and end of the century. Although the lack of accurate subsurface soil data within the study region prevented our discharge model from quantifying the changes in stream discharge, the strong correlation between the observed and simulated flow data as reflected by a 0.92 r2 statistic gave us confidence that discharge from the Slate River will continue to follow a decreasing trend as climate change persists into the future. This study aims to support the future endeavours of hydrologic modelling of watersheds in Northern Ontario by illustrating the current capabilities and limits of climate change analysis studies within this region.

Download or read book Physically Based Modelling of the Impacts of Climate Change on Streamflow Regime written by Nazmus Shams Sazib and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the implications of climate change on streamflow regime is complex as changes in climate vary over space and time. However, a better understanding of the impact of climate change is required for identifying how stream ecosystems vulnerable to these changes, and ultimately to guide the development of robust strategies for reducing risk in the face of changing climatic conditions. Here I used physically based hydrologic modeling to improve understanding of how climate change may impact streamflow regimes and advance some of the cyberinfrastructure and GIS methodologies that support physically based hydrologic modeling by: (1) using a physically based model to examine the potential effects of climate change on ecologically relevant aspects of streamflow regime, (2) developing data services in support of input data preparation for physically based distributed hydrologic models, and (3) enhancing terrain analysis algorithms to support rapid watershed delineation over large area. TOPNET, a physically based hydrologic model was applied over eight watersheds across the U.S to assess the sensitivity and changes of the streamflow regime due to climate change. Distributed hydrologic models require diverse geospatial and time series inputs, the acquisition and preparation of which are labor intensive and difficult to reproduce. I developed web services to automate the input data preparation steps for a physically based distributed hydrological model to enable water scientist to spend less time processing input data. This input includes terrain analysis and watershed delineation over a large area. However, limitations of current terrain analysis tools are (1) some support only a limited set of specific raster and vector data formats, and (2) all that we know of require data to be in a projected coordinate system. I enhanced terrain analysis algorithms to extend their generality and support rapid, web-based watershed delineation services. Climate change studies help to improve the scientific foundation for conducting climate change impacts assessments, thus building the capacity of the water management community to understand and respond to climate change. Web-based data services and enhancements to terrain analysis algorithms to support rapid watershed delineation will impact a diverse community of researchers involved terrain analysis, hydrologic and environmental modeling.

Download or read book Assessment of Impacts of Upstream Developments and Climate Change on Carp River Watershed written by Baba-Serges Zango and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A SWAT hydrological model is developed to evaluate the individual and combined impacts of urbanization and climate change on water quantity (discharge) and quality (N and P) of the watershed of Carp River in Ontario, Canada. Seven numerical experiments (scenarios) were developed to represent the different configurations of the watershed in terms of land use (either current or projected) and climate regime (current or future, observed or simulated). The reference period is 1990-2018, and the future period is 2021-2050. The 2017 land use was used to represent the reference period. The future land use is the projected 2050 land use obtained from the City of Ottawa. The future climate was obtained by downscaling the outputs of nine (9) Regional Climate Models (RCMs) under two Representative Concentration Pathways (RCPs): RCP4.5 and RCP 8.5. The developed scenarios are the following: • S0o (baseline scenario) corresponding to the current land use map and the observed climate regime on the reference period • S0m is similar to S0o except that RCM outputs are used instead of the observed climate on the reference period • S1 corresponds to the future land use and historical climate regime on the reference period. • S0M45/S0M85 corresponds to the current land use and the future climate regime under RCP4.5 (S0M45) and RCP8.5 (S0M85) • S1M45/S1M85 corresponds to the future land use map and future climate regime under the two RCPs. The changes or impacts on quantity and quality in each scenario were estimated by comparing the results with the baseline scenarios S0o/m (reference) at two levels: globally (at the main outlet) and locally (at the outlet of an upstream sub-watershed). For a consistency purpose, S0o is used when assessing land-use change scenario while S0m was the reference in climate change and combined effects scenario. This allowed the comparison to be consistent with the same climate data frame. The results showed that climate change is likely to be the most dominant factor affecting discharge and nitrogen, while urbanization will control the quantity of phosphorus. Unsurprisingly, the combined effect had a more significant impact on water quantity and quality. However, the impact is not additive, and the relationship is not linear. Compared with S0, the annual average discharge increased by 1.57%, 5.49%, 7.52%, 6.75%, and 9.34% in S1, S0M45, S0M85, S1M45, and S1M85, respectively. In comparison, the change for annual N load was estimated at -1.88%, 29.62%, 2.03%, 24.84%, and -1.20% respectively. Change in annual average P was respectively 26.49%, 1.07%, -4.49%, 23.81% and 19.15%. Local impact assessment indicates the impact in upstream sub-watersheds may differ from the main outlet's impact in terms of magnitude and direction of change. Therefore, only considering global change may lead to a wrong interpretation of the impacts over the watershed. It is, therefore, necessary to evaluate the impacts at the local level as well.

Download or read book Ecohydrologic Impacts of Climate and Land Use Changes on Watershed Systems written by Paul A. Ekness and published by . This book was released on 2013 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maintaining flows and quality of water resources is critical to support ecosystem services and consumptive needs. Understanding impacts of changes in climate and land use on ecohydrologic processes in a watershed is vital to sustaining water resources for multiple uses. This study completes a continental and regional scale assessment using statistical and simulation modeling to investigate ecohydrologic impacts within watershed systems. Watersheds across the continental United States have diverse hydrogeomorphic characters, mean temperatures, soil moistures, precipitation and evaporation patterns that influence runoff processes. Changes in climate affect runoff by impacting available soil moisture, evaporation, precipitation and vegetative patterns. A one percent increase in annual soil moisture may cause a five percent increase in runoff in watersheds across the continent. Low soil moisture and high temperatures influence runoff patterns in specific regions. Spring runoff is increased by the influence Spring soil moisture, Winter and Spring evaporation, and Winter and Spring evaporation. Spring runoff is decreased by increases in Winter and Spring temperatures and increases in the vegetation index. Winter runoff is affected by maximum vegetative index, temperature, soil moisture, evaporation and precipitation. Contributing factors to runoff are influenced by geomorphic and seasonal variations requiring strategies that are site-specific and use system-wide information. Regional scale watershed analysis investigates the influence of landscape metrics on temporal streamflow processes in multiple gauged watersheds in Massachusetts, U.S.A. Time of concentration, recession coefficient, base flow index, and peak flow are hydrologic metrics used to relate to landscape metrics derived using FRAGSTAT software. Peak flow increases with increasing perimeter-area fractal dimensions, and Contagion index and decreases as Landscape Shape Index increases. There was an increasing trend in the fractal dimension over time indicative of more complex shape of patches in watershed. Base flow index and recession coefficient fluctuated from low to high decreasing recently. This could be indicative of open space legislation, conservation efforts and reforestation within the state in the last ten years. Coastal systems provide valuable ecosystem services and are vulnerable to impacts of changes in climate and continental land use patterns. Effects of land use and climate change on runoff, suspended sediments, total nitrogen and total phosphorus are simulated for coastal watersheds around the Boston Bay ecosystem. The SWAT (Soil and Water Assessment Tool) model, a continuous-time, semi distributed, process-based model, is used to simulate the watershed ecohydrologic process affecting coastal bodies. Urbanization in watersheds increased runoff by as much as 80% from the baseline. Land use change poses a major threat to water quality impacts affecting coastal ecosystems. Total nitrogen increased average of 53.8% with conservative changes in climate and land use. Total phosphorus increased an average of 57.3% with conservative changes in land use and climate change. Climate change alone causes up to 40% increase in runoff and when combined with a 3.25% increase in urban development runoff increased an average of 114%. Coastal ecosystems are impacted by nutrient runoff from watersheds. Continued urbanization and changes in climate will increase total nitrogen, total phosphorus and suspended sediments in coastal ecosystems. Continental scale runoff is affected by soil moisture and vegetative cover. Cover crops, low tillage farm practices and natural vegetation contribute to less runoff. Developing policies that encourage protection of soil structure could minimize runoff and aid in maintaining sustainable water resources. Best Management Practices and Low impact development at the national level with continued stormwater legislation directed towards sustainable land use policy will improve water quantity and quality. Fragmentation observed in Massachusetts increases the number of urban parcels and decreases the size of forested areas. Faster runoff patterns are observed but recent land management may be changing this runoff pattern. Municipal and state zoning ordinance to preserve open space and large forest patches will restrict urban growth to specific regions of a watershed. This could improve quantities of water available to ecosystems. Increases in total nitrogen, phosphorus and suspended sediments to coastal ecosystems can be minimized with use of riparian buffers and Best Management Practices within coastal watersheds. Urbanization and climate change threatens coastal ecosystems and national policy to preserve and restrict development of coastal areas will preserve coastal ecosystem services.

Download or read book Watershed Hydrology written by Vijay P. Singh and published by Allied Publishers. This book was released on 2003 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Climate Variability and Land Use Change on the Water Budget of Large River Basins written by Ruud T. W. L. Hurkmans and published by . This book was released on 2009 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Case Study for Assessing the Hydrologic Impacts of Climate Change at the Watershed Scale written by Martinus Hubertus Brouwers and published by . This book was released on 2007 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the advent of the industrial era atmospheric concentrations of greenhouse gases have been on the rise leading to increasing global mean temperatures. Through increasing temperatures and changes to distributions of precipitation, climate change will intensify the hydrologic cycle which will directly impact surface water sources while the impacts to groundwater are reflected through changes in recharge to the water table. The IPCC (2001) reports that limited investigations have been conducted regarding the impacts of climate change to groundwater resources. The complexity of evaluating the hydrologic impacts of climate change requires the use of a numerical model. This thesis investigates the state of the science of conjunctive surface-subsurface water modeling with the aim of determining a suitable approach for conducting long-term transient simulations at the watershed scale. As a result of this investigation, a coupled modeling approach is adopted using HELP3 to simulate surface and vadose zone processes and HydroSphere to simulate saturated flow of groundwater. This approach is applied to the Alder Creek Watershed, which is a subwatershed of the Grand River Watershed and located near Kitchener-Waterloo, Ontario. The Alder Creek Watershed is a suitable case study for the evaluation of climate change scenarios as it has been well characterized from previous studies and it is relatively small in size. Two contrasting scenarios of climate change (i.e., drier and wetter futures) are evaluated relative to a reference scenario that is based on the historical climatic record of the region. The simulation results show a strong impact upon the timing of hydrologic processes, shifting the spring snow melt to earlier in the year leading to an overall decrease in runoff and increase in infiltration for both drier and wetter future climate scenarios. Both climate change scenarios showed a marked increase to overall evapotranspiration which is most pronounced in the summer months. The impacts to groundwater are more subdued relative to surface water. This is attributed to the climate forcing perturbations being attenuated by the shift of the spring snow melt and the transient storage effects of the vadose zone, which can be significant given the hummocky terrain of the region. The simulation results show a small overall rise of groundwater elevations resulting from the simulated increase in infiltration for both climate change scenarios.

Download or read book Hydro Environmental Impact of Climate and Land Use Change on Watersheds for Sustainable Development written by T. I. Eldho and published by . This book was released on 2024-07 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book includes the most up-to-date research findings on the topics of climate change impact assessment, land use change impact assessment, mathematical modelling, and field applications presented as case studies in the water resources engineering discipline. The book covers various aspects of hydrological and environmental processes; provides a comprehensive treatment of climate change and land use changes and their impacts, illustrated with case studies; and demonstrates recent modelling techniques for hydrological and environmental impact studies. The book may serve graduate students, engineers, professors, and researchers in providing a concise overview of climate and land use change and its impacts on hydrology, water resources, and the environment.

Download or read book Predicting the Impacts of Land Use and Climate on Regional scale Hydrologic Fluxes written by Anthony D. Kendall and published by . This book was released on 2009 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: