Hydrology And Global Environmental Change

Hydrology and Global Environmental Change presents the hydrological contribution to, and consequences of, global environmental change. Assuming little or no prior knowledge on the part of the reader, the book looks at the main processes of global environmental change - global scale processes, large regional processes, repetitive processes - and how the hydrological cycle, processes and regimes impact on GEC and vice-versa.

Examines the implications of possible climate changes and variability on both global and regional water resources.

Global climate change is typically understood and modeled using global climate models (GCMs), but the outputs of these models in terms of hydrological variables are only available on coarse or large spatial and time scales, while finer spatial and temporal resolutions are needed to reliably assess the hydro-environmental impacts of climate change. To reliably obtain the required resolutions of hydrological variables, statistical downscaling is typically employed. Statistical Downscaling for Hydrological and Environmental Applications presents statistical downscaling techniques in a practical manner so that both students and practitioners can readily utilize them. Numerous methods are presented, and all are illustrated with practical examples. The book is written so that no prior background in statistics is needed, and it will be useful to graduate students, college faculty, and researchers in hydrology, hydroclimatology, agricultural and environmental sciences, and watershed management. It will also be of interest to environmental policymakers at the local, state, and national levels, as well as readers interested in climate change and its related hydrologic impacts. Features: Examines how to model hydrological events such as extreme rainfall, floods, and droughts at the local, watershed level. Explains how to properly correct for significant biases with the observational data normally found in current Global Climate Models (GCMs). Presents temporal downscaling from daily to hourly with a nonparametric approach. Discusses the myriad effects of climate change on hydrological processes.

Climate theory dictates that core elements of the climate system, including precipitation, evapotranspiration, and reservoirs of atmospheric and soil moisture, should change as the climate warms, both in their means and extremes. A major challenge that faces the climate and hydrologic science communities is understanding the nature of these ongoing changes in climate and hydrology and the apparent anomalies that exist in reconciling their extreme manifestations. The National Research Council (NRC) Committee on Hydrologic Science (COHS) held a workshop on January 5-6, 2010, that examined how climate warming translates into hydrologic extremes like floods and droughts. The workshop brought together three groups of experts. The first two groups consisted of atmospheric scientists and hydrologists focused on the scientific underpinnings and empirical evidence linking climate variability to hydrologic extremes. The third group consisted of water managers and decision-makers charged with the design and operation of water systems that in the future must be made resilient in light of a changing climate and an environment of hydrologic extremes. Global Change and Extreme Hydrology summarizes the proceedings of this workshop. This report presents an overview of the current state of the science in terms of climate change and extreme hydrologic events. It examines the "conventional wisdom" that climate change will "accelerate" the hydrologic cycle, fuel more evaporation, and generate more precipitation, based on an increased capacity of a warmer atmosphere to hold more water vapor. The report also includes descriptions of the changes in frequency and severity of extremes, the ability (or inability) to model these changes, and the problem of communicating the best science to water resources practitioners in useful forums.

This volume brings together insights on the interactions between environmental change and human security in the Middle East and Africa. These regions face particular challenges in relation to environmental degradation, the decline of natural resources and consequent risks to current and future human security. The chapters provide topical analysis from a range of disciplines on the theory, discourse, policy and practice of responding to global environmental change and threats to human security. Case studies from Morocco, Tunisia, Egypt, Turkey, Iraq and Syria provide empirical evidence, with a focus section dedicated to the critical issue of water resources and water security in the region. The contributions demonstrate above all that the risks posed to human security arise through multiple and interconnected processes operating across diverse spatial and temporal scales. The complexity of these processes requires new ways of thinking and intervening. As a contribution, the current volume provides engaging insights from theory and practice for those seeking to address the challenges of environmental change.

Water is an extremely important factor in global environmental change. Water influences the processes causing change. The human and economic consequences of changes in the water system can be very significant. The aim of this NATO Advanced Study Institute was to present a state-of-the-art assessment of the role of water in global change, ranging from a consideration of atmospheric processes to the social and political impacts of changes in water resources. Many initiatives have recently been developed, such as international conferences and research programmes in particular themes, but there was still a need for information from these diverse activities to be brought together. One of the aims of the ASI was to encourage cross-fertilization between the various disciplines looking at water in the global system. This book contains the expanded written versions of the lectures presented during the AS! held in Italy in May/June 1994. It falls into two basic parts. The first twelve chapters cover the role of water in the climate system and climate modelling. Various areas of the water balance including global budgets, the effect of each element of the water balance on regional and global climates, and procedures used to model hydrological processes at all scales are discussed. Precipitation, ice, lake, groundwater, land surface and atmospheric considerations are included together with hydrological process linkage to climate models. Ocean effects were not covered as they were considered to be outside the scope of this particular AS!.

Hydrology and Global Environmental Change presents the hydrological contribution to, and consequences of, global environmental change. Assuming little or no prior knowledge on the part of the reader, the book looks at the main processes of global environmental change - global scale processes, large regional processes, repetitive processes - and how the hydrological cycle, processes and regimes impact on GEC and vice-versa.

This book offers a comprehensive overview of the challenges in hydrological modeling. Hydrology, on both a local and global scale, has undergone dramatic changes, largely due to variations in climate, population growth and the associated land-use and land-cover changes. Written by experts in the field, the book provides decision-makers with a better understanding of the science, impacts, and consequences of these climate and land-use changes on hydrology. Further, offering insights into how the changing behavior of hydrological processes, related uncertainties and their evolution affect the modeling process, it is of interest for all researchers and practitioners using hydrological modeling.