This volume provides an up to date overview of climate variability during the 20th century in the context of natural and anthropogenic variability. It compiles a number of contributions to a workshop held in Gwatt, Switzerland, in July 2006 dealing with different aspects of climate change, variability, and extremes during the past 100 years. The individual contributions cover a broad range of topics. The volume fills a gap in this exciting field of research.

A top priority in climate research is obtaining broad-extent and long-term data to support analyses of historical patterns and trends, and for model development and evaluation. Along with directly measured climate data from the present and recent past, it is important to obtain estimates of long past climate variations spanning multiple centuries and millennia. These longer time perspectives are needed for assessing the unusualness of recent climate changes, as well as for providing insight on the range, variation and overall dynamics of the climate system over time spans exceeding available records from instruments, such as rain gauges and thermometers. Tree rings have become increasingly valuable in providing this long-term information because extensive data networks have been developed in temperate and boreal zones of the Earth, and quantitative methods for analyzing these data have advanced. Tree rings are among the most useful paleoclimate information sources available because they provide a high degree of chronological accuracy, high replication, and extensive spatial coverage spanning recent centuries. With the expansion and extension of tree-ring data and analytical capacity new climatic insights from tree rings are being used in a variety of applications, including for interpretation of past changes in ecosystems and human societies. This volume presents an overview of the current state of dendroclimatology, its contributions over the last 30 years, and its future potential. The material included is useful not only to those who generate tree-ring records of past climate-dendroclimatologists, but also to users of their results-climatologists, hydrologists, ecologists and archeologists. 'With the pressing climatic questions of the 21st century demanding a deeper understanding of the climate system and our impact upon it, this thoughtful volume comes at critical moment. It will be of fundamental importance in not only guiding researchers, but in educating scientists and the interested lay person on the both incredible power and potential pitfalls of reconstructing climate using tree-ring analysis.', Glen M. MacDonald, UCLA Institute of the Environment, CA, USA 'This is an up-to-date treatment of all branches of tree-ring science, by the world's experts in the field, reminding us that tree rings are the most important source of proxy data on climate change. Should be read by all budding dendrochronology scientists.', Alan Robock, Rutgers University, NJ, USA

The Medieval Warm Period and the Little Ice Age are widely considered to have been the major features of the Earth's climate over the past 1000 years. In this volume the issue of whether there really was a Medieval Warm Period, and if so, where and when, is addressed. The types of evidence examined include historical documents, tree rings, ice cores, glacial-geological records, borehole temperature, paleoecological data and records of solar receipts inferred from cosmogenic isotopes. Growth in the availability of several of these types of data in recent years, and technical advances in their derivation and use, warrant this state-of-the-art re-examination of Medieval Warm Period. The book will be of value to all those with an interest in the natural variability of the climate system, for example those concerned with anticipating and detecting anthropogenic climate change.

Hurricanes of the North Atlantic Ocean have left their imprint on the landscape and human cultures for thousands of years. In modern times, fewer lifes have been lost due, in part, to the development of modern communication systems, and to improved understanding of the mechanisms of storm formation and movement. However, the immense growth of human populations in coastal areas, which are at risk to hurricanes, has resulted in very large increases in the amount of property damage sustained in the last decade in the Atlantic, Gulf of Mexico and Caribbean regions. This book is of interest to climatologists and meteorologists and as source of information for policymakers and emergency management planners.

This book provides a unique, in-depth view of past, present and potential future climatic change in mountain regions, and in particular on the mechanisms which are responsible for this change. Other books which focus on environmental change in mountains focus more generally on the impacts of this change on mountain systems, rather than on the regional features of climatic change itself. The book enters into a high level of detail concerning results of international investigations which involve specialists from numerous climate-related disciplines. The book can be used in an academic and research context, for advanced graduate and doctoral students, as well as researchers working in various domains of relevance to climatic change issues. The book also has relevance in the context of future activities of the Intergovernmental Panel on Climate Change (IPCC), in terms of providing up-to-date knowledge of fundamental mechanisms and consequences of climatic change in mountain regions.

A top priority in climate research is obtaining broad-extent and long-term data to support analyses of historical patterns and trends, and for model development and evaluation. Along with directly measured climate data from the present and recent past, it is important to obtain estimates of long past climate variations spanning multiple centuries and millennia. These longer time perspectives are needed for assessing the unusualness of recent climate changes, as well as for providing insight on the range, variation and overall dynamics of the climate system over time spans exceeding available records from instruments, such as rain gauges and thermometers. Tree rings have become increasingly valuable in providing this long-term information because extensive data networks have been developed in temperate and boreal zones of the Earth, and quantitative methods for analyzing these data have advanced. Tree rings are among the most useful paleoclimate information sources available because they provide a high degree of chronological accuracy, high replication, and extensive spatial coverage spanning recent centuries. With the expansion and extension of tree-ring data and analytical capacity new climatic insights from tree rings are being used in a variety of applications, including for interpretation of past changes in ecosystems and human societies. This volume presents an overview of the current state of dendroclimatology, its contributions over the last 30 years, and its future potential. The material included is useful not only to those who generate tree-ring records of past climate-dendroclimatologists, but also to users of their results-climatologists, hydrologists, ecologists and archeologists. 'With the pressing climatic questions of the 21st century demanding a deeper understanding of the climate system and our impact upon it, this thoughtful volume comes at critical moment. It will be of fundamental importance in not only guiding researchers, but in educating scientists and the interested lay person on the both incredible power and potential pitfalls of reconstructing climate using tree-ring analysis.', Glen M. MacDonald, UCLA Institute of the Environment, CA, USA 'This is an up-to-date treatment of all branches of tree-ring science, by the world's experts in the field, reminding us that tree rings are the most important source of proxy data on climate change. Should be read by all budding dendrochronology scientists.', Alan Robock, Rutgers University, NJ, USA

This volume provides an up to date overview of climate variability during the 20th century in the context of natural and anthropogenic variability. It compiles a number of contributions to a workshop held in Gwatt, Switzerland, in July 2006 dealing with different aspects of climate change, variability, and extremes during the past 100 years. The individual contributions cover a broad range of topics. The volume fills a gap in this exciting field of research.

The Hadley and Walker Circulations are fundamental regulators of the Earth's energy budget. Although the Hadley Circulation is a well-known concept, surprisingly little attention has been paid to understanding both short and long-term variability of the system. This book reviews current knowledge of Hadley and Walker circulation dynamics and their interactions with the major global monsoon systems, and evaluates paleoclimatic records within the domain of the Hadley Circulation that shed light on past variability of climate over the last 1000 years, the Holocene (the last 11,500 years), glacial periods, and warm climate periods in the past. The book examines potentially important factors that may have affected the Hadley and Walker Circulations on these different time scales and evaluates changes in the Hadley Circulation and the monsoons as simulated by coupled models of past climate conditions, and predicted future conditions under an enhanced greenhouse effect. This book is meant to serve as a fundamental reference work for current and future researchers, graduate students in the atmospheric sciences and geosciences, and climate specialists involved in interdisciplinary research.

Climate and Water: Transboundary Challenges in the Americas explores some of the ways that climate, hydrology, and water resource management converge at the borders between jurisdictions and countries in the western Hemisphere. This book is unique in focusing on case studies of climate-hydrology-water resource management in diverse contexts in South, Central, and North America. This book is singular in highlighting important problems arising from the very existence of boundaries drawn and defined by society. Addressing such problems takes on increasing urgency as the world becomes ever more inter connected and interdependent.

Target groups for this book include water resource managers and decision makers at levels from the international to the local; scientists involved in interdisciplinary studies of basic and applied climatology, hydrology, and environmental studies; and readers specializing in institutional analyses, including transboundary water law, policy analysis, and risk assessment. This book is also a useful text for college classes addressing natural resources management in general, and the transfer of scientific knowledge to society.

Glaciers in the Andes are particularly important natural archives of present and past climatic and environmental changes, in significant part because of the N-S trend of this topographic barrier and its influence on the atmospheric circulation of the southern hemisphere. Strong gradients in the seasonality and amount of precipitation exist between the equator and 30 Degrees S. Large differences in amount east and west of the Andean divide also occur, as well as a change from tropical summer precipitation (additionally modified by the seasonal shift of the circulation belts) to winter precipitation in the west wind belt (e. g. , Yuille, 1999; Garraud and Aceituno, 2001). The so-called 'dry axis' lies between the tropical and extra tropical precipitation regimes (Figure 1). The high mountain desert within this axis responds most sensitively to the smallest changes in effective moisture. An important hydro-meteorological feature on a seasonal to inter-annual time-scale is the occurrence of EN SO events, which strongly control the mass balance of glaciers in this area (e. g. , Wagnon et ai. , 2001; Francou et ai. , in press). The precipitation pattern is an important factor for the interpretation of climatic and environmental records extracted from ice cores, because much of this information is related to conditions at the actual time of precipitation, and this is especially so for stable isotope records. Several ice cores have recently been drilled to bedrock in this area. From Huascanin (Thompson et ai. , 1995), Sajama (Thompson et ai.

This book provides a unique, in-depth view of past, present and potential future climatic change in mountain regions, and in particular on the mechanisms which are responsible for this change. Other books which focus on environmental change in mountains focus more generally on the impacts of this change on mountain systems, rather than on the regional features of climatic change itself. The book enters into a high level of detail concerning results of international investigations which involve specialists from numerous climate-related disciplines. The book can be used in an academic and research context, for advanced graduate and doctoral students, as well as researchers working in various domains of relevance to climatic change issues. The book also has relevance in the context of future activities of the Intergovernmental Panel on Climate Change (IPCC), in terms of providing up-to-date knowledge of fundamental mechanisms and consequences of climatic change in mountain regions.

The Medieval Warm Period and the Little Ice Age are widely considered to have been the major features of the Earth's climate over the past 1000 years. In this volume the issue of whether there really was a Medieval Warm Period, and if so, where and when, is addressed. The types of evidence examined include historical documents, tree rings, ice cores, glacial-geological records, borehole temperatures, paleoecological data and records of solar receipts inferred from cosmogenic isotopes. Growth in the availability of several of these types of data in recent years, and technical advances in their derivation and use, warrant this state-of-the-art re-examination of the Medieval Warm Period. The book will be of value to all those with an interest in the natural variability of the climate system, for example those concerned with anticipating and detecting human-produced climate change.

Extreme climatic events present society with significant challenges in a rapidly warming world. Ordinary citizens, the insurance industry and governments are concerned about the apparent increase in the frequency of weather and climate events causing extreme, and in some instances, catastrophic, impacts. Originally published in 2008, Climate Extremes and Society focuses on the recent and potential future consequences of weather and climate extremes for different socioeconomic sectors. The book also examines actions that may enable society to better respond to climate variability. It provides examples of the impact of climate and weather extremes on society. How have these extremes varied in the past, and how might they change in the future? What type of efforts will help society adapt to potential future changes in climate and weather extremes? The book is designed for all policy-makers, engineers and scientists who have an interest in the effects of climate extremes on society.

The El Nino/Southern Oscillation (ENSO) phenomenon is a recurrent feature of the climate in tropical regions. A primary example of large scale coupled ocean-atmosphere interactions, ENSO has received much attention in past years, as a result of widespread climatic anomalies (severe drought and floods, Indian monsoon failure, etc.) that are often associated with the development of such episodes. To enhance our understanding of the mechanisms involved in the low frequency behavior of ENSO and to help improve our ability to forecast the future behavior of this phenomenon, we have combined analysis of the modern aspects of ENSO morphology, modelling and variability with chapters dealing with its historical and prehistorical behavior. this volume examines different approaches to reconstructing ENSO based on a variety of proxy sources. It also illustrates how, in the past, the climatic manifestations associated with ENSO may have been different, in the frequency of occurrence as well as amplitude. This 1993 book will be of importance to all professional scientists and researchers in climatology, meteorology and the earth and environmental sciences, while graduate students in these disciplines will find the book a useful reference source.

The El Nino/Southern Oscillation (ENSO) phenomenon is a recurrent feature of the climate in tropical regions. A primary example of large scale coupled ocean-atmosphere interactions, ENSO has received much attention in past years, as a result of widespread climatic anomalies (severe drought and floods, Indian monsoon failure, etc.) that are often associated with the development of such episodes. To enhance our understanding of the mechanisms involved in the low frequency behavior of ENSO and to help improve our ability to forecast the future behavior of this phenomenon, we have combined analysis of the modern aspects of ENSO morphology, modelling and variability with chapters dealing with its historical and prehistorical behavior. this volume examines different approaches to reconstructing ENSO based on a variety of proxy sources. It also illustrates how, in the past, the climatic manifestations associated with ENSO may have been different, in the frequency of occurrence as well as amplitude. This 1993 book will be of importance to all professional scientists and researchers in climatology, meteorology and the earth and environmental sciences, while graduate students in these disciplines will find the book a useful reference source.