Quaternary Environmental Change in the Tropics


Book Description

The global climate changes that led to the expansion and contraction of high latitude ice sheets during the Quaternary period were associated with equally dramatic changes in tropical environments. These included shifts in vegetation zones, changes in the hydrology and ecology of lakes and rivers, and fluctuations in the size of mountain glaciers and sandy deserts. Until recently it was thought that such changes were triggered by fluctuations in the distribution of polar ice cover. Now there is increasing recognition that the tropics themselves have acted as drivers of global climate change over a range of timescales. The aim of Quaternary Environmental Change in the Tropics is to provide a synthesis of the changes that occurred in tropical terrestrial and marine systems during the Pleistocene and Holocene, complementing data-derived reconstructions with output from state-of-the-art climate models. It is targeted at final-year undergraduate students and research specialists, but will provide an introduction to tropical Quaternary research for a variety of other readers.




Climate Variability and Change in High Elevation Regions: Past, Present & Future


Book Description

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° 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.




Past Climate Variability in South America and Surrounding Regions


Book Description

South America is a unique place where a number of past climate archives are ava- able from tropical to high latitude regions. It thus offers a unique opportunity to explore past climate variability along a latitudinal transect from the Equator to Polar regions and to study climate teleconnections. Most climate records from tropical and subtropical South America for the past 20,000 years have been interpreted as local responses to shift in the mean position and intensity of the InterTropical Conv- gence Zone due to tropical and extratropical forcings or to changes in the South American Summer Monsoon. Further South, the role of the Southern Hemisphere westerly winds on global climate has been highly investigated with both paleodata and coupled climate models. However the regional response over South America during the last 20,000 years is much more variable from place to place than pre- ously thought. The factors that govern the spatial patterns of variability on millennial scale resolution are still to be understood. The question of past natural rates and ranges of climate conditions over South America is therefore of special relevance in this context since today millions of people live under climates where any changes in monsoon rainfall can lead to catastrophic consequences.




Tropical Geomorphology


Book Description

Although similar geomorphic processes take place in other regions, in the tropics these processes operate at different rates and with varying intensities. Tropical geomorphology therefore provides many new discoveries regarding geomorphic processes. This textbook describes both the humid and arid tropics. It provides thoroughly up-to-date concepts and relevant case studies, and emphasises the importance of geomorphology in the management and sustainable development of the tropical environment, including climate change scenarios. The text is supported by a large number of illustrations, including satellite images. Student exercises accompany each chapter. Tropical Geomorphology is an ideal textbook for any course on tropical geomorphology or the tropical environment, and is also invaluable as a reference text for researchers and environmental managers in the tropics.




The Quaternary in the Tropics


Book Description




Tropical Rainforest Responses to Climatic Change


Book Description

This updated and expanded second edition of a much lauded work provides a current overview of the impacts of climate change on tropical forests. The authors also investigate past, present and future climatic influences on the ecosystems with the highest biodiversity on the planet. Tropical Rainforest Responses to Climatic Change, Second Edition, looks at how tropical rain forest ecology is altered by climate change, rather than simply seeing how plant communities were altered. Shifting the emphasis on to ecological processes, e.g. how diversity is structured by climate and the subsequent impact on tropical forest ecology, provides the reader with a more comprehensive coverage. A major theme of the book is the interaction between humans, climate and forest ecology. The authors, all foremost experts in their fields, explore the long term occupation of tropical systems, the influence of fire and the future climatic effects of deforestation, together with anthropogenic emissions. Incorporating modelling of past and future systems paves the way for a discussion of conservation from a climatic perspective, rather than the usual plea to stop logging. This second edition provides an updated text in this rapidly evolving field. The existing chapters are revised and updated and two entirely new chapters deal with Central America and the effect of fire on wet forest systems. In the first new chapter, the paleoclimate and ecological record from Central America (Lozano, Correa, Bush) is discussed, while the other deals with the impact of fire on tropical ecosystems. It is hoped that Jonathon Overpeck, who has been centrally involved in the 2007 and 2010 IPCC reports, will provide a Foreword to the book.







Understanding Earth's Deep Past


Book Description

There is little dispute within the scientific community that humans are changing Earth's climate on a decadal to century time-scale. By the end of this century, without a reduction in emissions, atmospheric CO2 is projected to increase to levels that Earth has not experienced for more than 30 million years. As greenhouse gas emissions propel Earth toward a warmer climate state, an improved understanding of climate dynamics in warm environments is needed to inform public policy decisions. In Understanding Earth's Deep Past, the National Research Council reports that rocks and sediments that are millions of years old hold clues to how the Earth's future climate would respond in an environment with high levels of atmospheric greenhouse gases. Understanding Earth's Deep Past provides an assessment of both the demonstrated and underdeveloped potential of the deep-time geologic record to inform us about the dynamics of the global climate system. The report describes past climate changes, and discusses potential impacts of high levels of atmospheric greenhouse gases on regional climates, water resources, marine and terrestrial ecosystems, and the cycling of life-sustaining elements. While revealing gaps in scientific knowledge of past climate states, the report highlights a range of high priority research issues with potential for major advances in the scientific understanding of climate processes. This proposed integrated, deep-time climate research program would study how climate responded over Earth's different climate states, examine how climate responds to increased atmospheric carbon dioxide and other greenhouse gases, and clarify the processes that lead to anomalously warm polar and tropical regions and the impact on marine and terrestrial life. In addition to outlining a research agenda, Understanding Earth's Deep Past proposes an implementation strategy that will be an invaluable resource to decision-makers in the field, as well as the research community, advocacy organizations, government agencies, and college professors and students.




The Holocene


Book Description

The Holocene provides students, researchers and lay-readers with the remarkable story of how the natural world has been transformed since the end of the last Ice Age around 15,000 years ago. This period has witnessed a shift from environmental changes determined by natural forces to those dominated by human actions, including those of climate and greenhouse gases. Understanding the environmental changes - both natural and anthropogenic - that have occurred during the Holocene is of crucial importance if we are to achieve a sustainable environmental future. Revised and updated to take full account of the most recent advances, the third edition of this classic text includes substantial material on the scientific methods that are used to reconstruct and date past environments, as well as new concepts such as the Anthropocene. The book is fully-illustrated, global in coverage, and contains case studies, a glossary and more than 500 new references.




Innovative Approaches Towards Low Carbon Economics


Book Description

Climate change is an inevitable and urgent global challenge with long-term implications for the sustainable development of all countries. To overcome this human crisis, the scientific consensus is driving global action towards low carbon economics. Though this action has to involve all sectors (industries, governments, and citizens) and at all levels (global, national and regional levels), the implementation of climate strategies will predominantly be at the regional level. By establishing an innovative range of model technologies, this book aims to develop systematic quantificational methods, such as uncertain multi-objective programming models and system dynamics models, to provide a new approach to low carbon economics that can serve as a paradigm for general regions. At the same time, it offers decision makers a number of effective strategies for some key issues in regional low carbon development, such as greenhouse gas control, ecological capacity evaluation, regional economic prediction, energy structure optimization, land resource utilization, industrial structure adjustment, low carbon industrial chains, low carbon transportation systems and low carbon tourism. It also provides researchers with a new perspective on how to address social problems using quantitative techniques.