An integrated, multi-model capability for regional climate change simulation is needed to perform original analyses to understand and prepare for the impacts of climate change on the time and space scales that are critical to California's future environmental quality and economic prosperity. Our intent was to develop a very high resolution regional simulation capability to address consequences of climate change in California to complement the global modeling capability that is supported by DOE at LLNL and other institutions to inform national and international energy policies. The California state government, through the California Energy Commission (CEC), institutionalized the State's climate change assessment process through its biennial climate change reports. The bases for these reports, however, are global climate change simulations for future scenarios designed to inform international policy negotiations, and are primarily focused on the global to continental scale impacts of increasing emissions of greenhouse gases. These simulations do not meet the needs of California public and private officials who will make major decisions in the next decade that require an understanding of climate change in California for the next thirty to fifty years and its effects on energy use, water utilization, air quality, agriculture and natural ecosystems. With the additional development of regional dynamical climate modeling capability, LLNL will be able to design and execute global simulations specifically for scenarios important to the state, then use those results to drive regional simulations of the impacts of the simulated climate change for regions as small as individual cities or watersheds. Through this project, we systematically studied the strengths and weaknesses of downscaling global model results with a regional mesoscale model to guide others, particularly university researchers, who are using the technique based on models with less complete parameterizations or coarser spatial resolution. Further, LLNL has now built a capability in state-of-the-science mesoscale climate modeling that complements that which it has in global climate simulation, providing potential sponsors with an end-to-end simulation and analysis program.

Drought is one of the likely consequences of climate change in many regions of the world. Together with an increased demand for water resources to supply the world's growing population, it represents a potentially disastrous threat to water supplies, agriculture and food production, leading to famine and environmental degradation. Yet predicting drought is fraught with difficulty. The aim of this book is to provide a review of the historical occurrence of global drought, particularly during the 20th century and assess the likely potential changes over the 21st century under climate change. This includes documentation of the occurrence and impacts of major 20th century drought events and analysis of the contributing climatic and environmental factors that act to force, prolong and dissipate drought. Contemporary drought is placed in the context of climate variability since the last ice age, including the many severe and lengthy drought events that contributed to the demise of great civilizations, the disappearance of lakes and rivers, and the conversion of forests to deserts. The authors discuss the developing field of drought monitoring and seasonal forecasting and describe how this is vital for identifying emerging droughts and for providing timely warning to help reduce the impacts. The book provides a broad overview of large scale drought, from historic events such as the US Dust Bowl and African Sahel, and places this in the context of climate variability and change. The work is soundly based on detailed research that has looked at drought occurrence over the 20th century, global drought monitoring, modelling and seasonal prediction, and future projections from climate models.

Drought (hydrological, meteorological, and/or agronomical) disturbs water balance in certain domains and limits green/blue water resources for our basic needs, including food and energy production. This book presents the most recent insights related to drought types, their detection, and their effects on food, energy, and municipal water supplies. It also examines some novel approaches to drought management.

Droughts occur in arid and semi-arid areas of the world, but also in humid areas, and can develop over short periods (flash drought) or longer periods (seasons/decades). Even though progress has been made, it remains difficult to adequately characterize, monitor, forecast and manage droughts, due to their multi-faceted nature.Usually, drought does

This assessment provides input to the reauthorized National Integrated Drought Information System (NIDIS) and the National Climate Assessment (NCA), and it establishes the scientific foundation needed to manage for drought resilience and adaptation. Focal areas include drought characterization; drought impacts on forest processes and disturbances such as insect outbreaks and wildfire; and consequences for forest and rangeland values. Drought can be a severe natural disaster with substantial social and economic consequences. Drought becomes most obvious when large-scale changes are observed; however, even moderate drought can have long-lasting impacts on the structure and function of forests and rangelands without these obvious large-scale changes. Large, stand-level impacts of drought are already underway in the West, but all U.S. forests are vulnerable to drought. Drought-associated forest disturbances are expected to increase with climatic change. Management actions can either mitigate or exacerbate the effects of drought. A first principal for increasing resilience and adaptation is to avoid management actions that exacerbate the effects of current or future drought. Options to mitigate drought include altering structural or functional components of vegetation, minimizing drought-mediated disturbance such as wildfire or insect outbreaks, and managing for reliable flow of water.

Comprehensive coverage of understanding, prevention, and risk management of extreme drought events, with examples of approaches followed in water-stressed regions This book describes the progress made in our understanding of severe drought and explains how we can deal with—and even avoid—complete devastation brought on by such punishing events. It brings forward advanced knowledge on drought hazard analysis and management, particularly from EU-funded research projects, to assist in the development of the corresponding drought management plans. In addition, this book addresses issues of social vulnerability to drought and science-policy interfaces, which are important elements of drought management. Divided into three sections, this book covers the diagnosis of physical processes, historic drought and the trends in historic drought, and perspectives of future drought. It takes an academic approach to risk evaluation, including characterization of drought episodes, development of indicators of risk in hydrological and agricultural systems, and analysis of the role of socio-economic instruments for risk mitigation. It also discusses the interactions that have resulted in the complex institutional framework, and highlights the importance of stakeholder involvement and awareness building for successful drought management. In addition, Drought: Science and Policy features a collection of case studies that include the description of effective measures taken in the past. Addresses the growing issue of drought preparedness planning, monitoring, and mitigation Teaches methodologies and lessons focused on specific, drought-prone regions so the applications have more significance Provides examples of approaches followed in water-stressed regions (river basin and national scale) with drought analyses at the pan-European scale Drought: Science and Policy will be an invaluable reference for researchers and practitioners in the field as well as Masters students taking relevant courses in drought management and natural disaster management.