Download or read book Modeling the Potential Impacts of Climate Change on Streamflow Variability in the North Fork of Elk Creek Experimental Watershed West Central Montana written by Katie Marie Jorgensen and published by . This book was released on 2012 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study hypothesizes the effects of global climate change on the hydrologic regime of West-Central Montana, focusing on the North Fork of Elk Creek, a 6.6 km2 (2.6 mi.2) Experimental Watershed. This is important to understand in snowmelt-dominated watersheds, as it is already well documented by current trends and future climate projections that the natural hydrologic regime is experiencing alterations. There have been shifts in the 20th century of the timing of snowmelt trending towards an earlier spring peak flows and declines in the overall snow water equivalent (Regonda et al., 2005; Mote et al., 2005; Hamlet et al., 2005). The goals for this study are to analyze for significant changes in the timing of important hydrologic events, and determine how discharge throughout the year will be altered in the Elk Creek Experimental Watershed (ECEW). To address these issues, a semi-spatial hydrologic model is employed, and run using current meteorological data and under downscaled climate-change scenarios conditions, under three relevant time periods. Snowmelt Runoff Model (SRM) is deterministic and conceptual and is used to generate streamflow in snowmelt dominated basins by the degree-day method (Martinec, 1985). Data is gathered from two SNOTEL sites located within the watershed and streamflow collected directly on the North Fork of Elk Creek. The specific metrics that will be statistically analyzed are mean summer and winter flows, and trends in peak flow and center of mass date timing (Wenger et al., 2009; Regonda et al., 2005). These results can be useful for management purposes because changes in the way water is released from the mountains affects water storage, flooding, and overall watershed resilience such that current practices may need to be accordingly adjusted.

Download or read book Potential Effects of Climate Change on Streamflow Eastern and Western Slopes of the Sierra Nevada California and Nevada written by Anne E. Jeton and published by . This book was released on 1996 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Watershed Scale Response to Climate Change South Fork Flathead River Basin Montana written by Katherine J. Chase and published by . This book was released on 2012 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Potential Impacts of Climate Change on Major Watersheds of Western North America written by Daniel Barandiaran and published by . This book was released on 2011 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modelling the Potential Impacts of Climate Change on Snowpack in the St Mary River Watershed Montana written by Ryan J. MacDonald and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate change poses significant threats to mountain ecosystems in North America (Barnett et al., 2005) and will subsequently impact water supply for human and ecosystem use. To assess these threats, we must have an understanding of the local variability in hydrometeorological conditions over the mountains. This thesis describes the continued development and application of a fine scale spatial hydrometeorological model, GENESYS (GENerate Earth SYstems Science input). The GENESYS model successfully simulated daily snowpack values for a 10 year trial period and annual runoff volumes for a thirty year period. Based on the results of these simulations the model was applied to estimate potential changes in snowpack over the St. Mary River watershed, Montana. GCM derived future climate scenarios were applied, representing a range of emissions controls and applied to perturb the 1961-90 climate record using the "delta" downscaling technique. The effects of these changes in climate were assessed for thirty year time slices centered on 2020s, 2050s, and 2080s. The GENESYS simulations of future climate showed that mountain snowpack was highly vulnerable to changes in temperature and to a lesser degree precipitation. A seasonal shift to an earlier onset of spring melt and an increase in the ratio of rain to snow occurred under all climate change scenarios. Results of mean and maximum snowpack were more variable and appeared to be highly dependent on scenario selection. The results demonstrated that although annual volume of available water from snowpack may increase, the seasonal distribution of available water may be significantly altered.

Download or read book Modeling the Effects of Climate Variability on Hydrology and Stream Temperatures in the North Fork of the Stillaguamish River written by Kyra Freeman and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forecast modeling indicates that the North Fork watershed will transition from a snow- to rain-dominated basin into the 21st century as a result of increasing air temperatures. More precipitation in the winter will fall as rain rather than snow, resulting in up to a 43% increase in streamflow and a 56% decline in basin-wide snowpack. The reduced snowpack will melt out earlier and cause a decrease in spring and summer streamflow. Simulations of stream temperature indicate rising temperatures in every stream segment in the basin by the end of the 21st century as a result of higher air temperatures, declining snowpack, and lower summer streamflow. Monthly average stream temperatures could increase by up to 7.4°C. In addition, the temperature thresholds for every life cycle of endangered salmon species are increasingly exceeded through time, putting at risk already endangered salmon species. By the end of the 21st century, the main stem may experience up to a 10-fold increase in number of days per year exceeding salmon temperature thresholds. Reach-scale predictions of stream temperature trends through the basin offer water resource managers a tool for focusing riparian and groundwater restoration efforts.

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 Modeling Hydrologic Responses to Forest Management and Climate Change in Contrasting Watersheds in the Southeastern United States written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrologic pathways and processes vary greatly from the coastal plain to the mountainous upland across the southeastern United States due to large physiographic and climatic gradients. The coastal plain is generally a groundwater dominated system with a shallow water table, while the mountainous upland is hillslope controlled system. It was hypothesized that these two different regions have different hydrologic responses to forest management and climate change due to different conditions: topography, climate, soil, and vegetation. The hydrologic impacts of climate change and forest management practices are complex and nonlinear, and a model is an advanced tool for addressing such tasks. The objectives of this study were: 1) to evaluate the applicability of a physically-based, distributed hydrologic modeling system - MIKE SHE/MIKE 11 - in the southeastern United States; and 2) to use the MIKE SHE/MIKE 11 modeling system to examine the hydrologic processes and responses to forest management practices and climate change on the coastal plain and the mountainous upland in the southeastern United States. Four experimental watersheds, three wetlands on the coastal plain and one Appalachian mountainous upland, were selected. The model was first evaluated to determine if it could sufficiently describe the hydrological processes in these diverse watersheds in two contrasting regions. Next, the model was applied to simulate the hydrologic impacts of forest management and climate change at the four study sites, four simulation scenarios per site. These included the base line, clearcut, 2 & deg;C temperature increase, and 10% precipitation decrease scenarios. Water table level and streamflow amount were two responses used to evaluate the forest management and climate change impacts. This study indicated that forest management and climate change would have potential impacts on the wetland water table, especially during dry periods. The absolute magnitudes of streamflow reduction w.

Download or read book Modeling the Effects of Climate Change Forecasts on Streamflow in the Nooksack River Basin written by Susan E. Dickerson and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Nooksack River has its headwaters in the North Cascade Mountains and drains an approximately 2300 km2 watershed in northwestern Washington State. The timing and magnitude of streamflow in a high relief, snow-dominated drainage basin such as the Nooksack River basin is strongly influenced by temperature and precipitation. Forecasts of future climate made by general circulation models (GCMs) predict increases in temperature and variable changes to precipitation in western Washington, which will affect streamflow, snowpack, and glaciers in the Nooksack River basin. Anticipating the response of the river to climate change is crucial for water resources planning because municipalities, tribes, and industry depend on the river for water use and for fish habitat. I combined modeled climate forecasts and the Distributed-Hydrology-Soil-Vegetation Model (DHSVM) to simulate future changes to timing and magnitude of streamflow in the higher elevations of the Nooksack River, east of the confluence near Deming, Washington. The DHSVM is a physically based, spatially distributed hydrology model that simulates a water and energy balance at the pixel scale of a digital elevation model. I used recent meteorological and landcover data to calibrate and validate the DHSVM. Coarse-resolution GCM forecasts were downscaled to the Nooksack basin following the methods of previous regional studies (e.g., Palmer, 2007) for use as local-scale meteorological input to the calibrated DHSVM. Simulations of future streamflow and snowpack in the Nooksack River basin predict a range of magnitudes, which reflects the variable predictions of the climate change forecasts and local natural variability. Simulation results forecast increased winter flows, decreased summer flows, decreased snowpack, and a shift in timing of the spring melt peak and maximum snow water equivalent. Modeling results for future peak flow events indicate an increase in both the frequency and magnitudes of floods, but uncertainties are high for modeling the absolute magnitudes of peak flows. These results are consistent with previous regional studies which document that temperature-related effects on precipitation and melting are driving changes to snow-melt dominated basins (e.g., Hamlet et al., 2005; Mote et al., 2005; Mote et al., 2008; Adam et al., 2009).

Download or read book The Impacts of Climate Change on New York Streamflows written by Ching-pin Tung and published by . This book was released on 1992 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Prediction of Climate Change Effects on Streamflow Regime Important to Stream Ecology written by Sulochan Dhungel and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A major challenge in freshwater ecosystem management is to predict future changes in streamflow regime. This thesis focused on identifying and modeling specific characteristics of streamflow that are important to stream ecosystems. The need to evaluate the potential impacts of climate change on stream ecosystems makes it important to study how streamflow regime may change. In this thesis we sought to advance understanding of the effect of climate change on streamflow regime by (1) examining the spatial variation in streamflow attributes across the continental US, (2) modeling how these streamflow attributes vary with current climate and watershed features, and (3) using this model with future climate projections of changes in precipitation and temperature to predict how streamflow attributes change with climate change. We used long-term daily flow measurements for 601 gauged streams whose watersheds were in relatively unimpaired condition to characterize streamflow regimes. Sixteen streamflow variables were identified which in our judgment sufficiently characterized aspects of the streamflow regime most relevant to stream ecosystem structure and function. These are computed for each stream. Principal component analysis with Varimax rotation reduced the dimensionality to five uncorrelated streamflow factors that quantify lowflow, magnitude, flashiness, timing and constancy. These independent factors were used to hereafter classify the streams based on distances in factor space into three broad classes which were further divided into eight classes. We used Random Forests to develop a model to predict these stream classes using watershed and climate attributes. The model had an accuracy of about 75%. Downscaled climate projections of precipitation and temperature were used to predict the changes in these stream classes by 2100 using the RF model. Thirty-three percent of selected sites were predicted to change into a different stream class by 2100. The least changes were predicted in snow-fed streams in the west while most of changes were predicted for rain-fed small perennial streams and intermittent streams in the central and eastern US. Class changes predicted, due to projected climate change provide a basis for (i) considering the extent of projected changes and (ii) formulating approaches to protect ecosystems that may be subject to change.

Download or read book Modeling the Effects of Climate Change on Streamflow and Stream Temperature in the South Fork of the Stillaguamish River written by Katherine Mary Clarke and published by . This book was released on 2020 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Stillaguamish River in northwest Washington State is an important regional water resource for local agriculture, industry, and First Nations tribes and a critical habitat for several threatened and endangered salmonid species, including the Chinook salmon. The river is currently subject to a temperature total maximum daily load, so it is important to understand how projected climate change will affect future stream temperatures and thus salmon populations. Snowpack is the main contributor to spring and summer streamflow and helps to mitigate stream temperatures as air temperatures rise through the summer in the South Fork of the Stillaguamish River. I used gridded historical meteorological data to calibrate the physically-based Distributed Hydrology Soil Vegetation Model and River Basin Model and then applied downscaled, gridded projected climate data to predict how a changing climate will influence hydrology and stream temperature in the South Fork basin through the end of the 21st century.

Download or read book Specialty Conference on Potential Consequences of Climate Variability and Change to Water Resources of the United States May 10 12 1999 written by D. Briane Adams and published by American Water Resources Association. This book was released on 1999 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling the Effects of Forecasted Climate Change and Glacier Recession on Late Summer Streamflow in the Upper Nooksack River Basin written by Ryan D. Murphy and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Like many watersheds in the North Cascades range of Washington State, USA, streamflow in the Nooksack River is strongly influenced by precipitation and snowmelt in the spring and glacial ice melt in the warmer summer months. With a maritime climate and high relief containing approximately 34km2 of glacial ice, the streamflow response in the Nooksack River basin is sensitive to increases in temperature. Climate projections from global climate models (GCMs) for the 21st Century indicate increases in temperature with variable changes to precipitation. The watershed is a valuable freshwater resource for regional municipalities, industry, and agriculture, and provides critical habitat for endangered salmon species. Thus, understanding the impacts of forecasted climate change is critical for water resources planning purposes. I apply publically available statistically derived 1/16 degree gridded surface climate data along with the Distributed Hydrology Soil Vegetation Model (DHSVM) with newly developed coupled dynamic glacier model to simulate hydrologic and glacial processes through the end of the 21st Century. Simulation results project median winter streamflows to more than double by 2075 due to more precipitation falling as rain rather than snow, and median summer flows to decrease by more than half with a general shift in peak snowmelt derived spring flows toward earlier in the spring. Glaciers are projected to retreat significantly with smaller glaciers disappearing entirely. Ice melt contribution to streamflow is likely to play an important role in sustaining summer baseflows in the Nooksack River. Glacier melt derived streamflow is projected to increase throughout the first half of the 21st century and decrease in the latter half after glacier ice volume decreases substantially.

Download or read book Hydrologic Conditions and Streamflow Change in an Evolving Semi Arid Agricultural Watershed Smith River Montana written by Andrea Stanley and published by . This book was released on 2013 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: Agricultural land and water use has modified natural flow regimes in the western US. Understanding the effect of agricultural water use on streamflow is critical to effective water management and is often limited by the available data record. This investigation evaluates agricultural water use and streamflow in the Smith River watershed (SRW), a semi-arid agricultural watershed located on the eastern slope of the northern Rocky Mountains in west-central Montana. Questions motivating this study include: (1) Has agricultural water use modified streamflow on the Smith River? (2) What aspect of agricultural activity in the Smith River watershed is having the greatest effect on streamflow? (3) What hydrologic properties of the watershed determine streamflow sensitivity to agricultural land and water use? Three approaches are employed to address these questions: (1) construction of an annual water budget, (2) comparison of streamflow to current and historic agricultural water use intensity, and (3) simulation of watershed processes using a precipitation-runoff model. Based on the mean-annual water budget estimate of the SRW, 12 percent of mean-annual streamflow in the Smith River is consumed by irrigation water use. The hydrologic effects of increased irrigated area detected with linear regression analyses of streamflow and agricultural water use include decreased seasonal flows in April, May, and June; increased late-summer flows in August and September; and increased low-flow volumes. Numerical hydrologic model simulations demonstrate that dominant precipitation-runoff processes in the watershed cannot be adequately represented without including agricultural water use.

Download or read book Climate Change at Mono Lake written by Christropher Andrew Kent and published by . This book was released on 1992 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: