The Geologic Record Of Climatic Change

In order to answer important questions about ecosystems and biodiversity, scientists can look to the past geological recordâ€"which includes fossils, sediment and ice cores, and tree rings. Because of recent advances in earth scientists' ability to analyze biological and environmental information from geological data, the National Science Foundation and the U.S. Geological Survey asked a National Research Council (NRC) committee to assess the scientific opportunities provided by the geologic record and recommend how scientists can take advantage of these opportunities for the nation's benefit. The committee identified three initiatives for future research to be developed over the next decade: (1) use the geological record as a "natural laboratory" to explore changes in living things under a range of past conditions, (2) use the record to better predict the response of biological systems to climate change, and (3) use geologic information to evaluate the effects of human and non-human factors on ecosystems. The committee also offered suggestions for improving the field through better training, improved databases, and additional funding.

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.

Reconstructing Earth’s Climate History There has never been a more critical time for students to understand the record of Earth’s climate history, as well as the relevance of that history to understanding Earth’s present and likely future climate. There also has never been a more critical time for students, as well as the public-at-large, to understand how we know, as much as what we know, in science. This book addresses these needs by placing you, the student, at the center of learning. In this book, you will actively use inquiry-based explorations of authentic scientific data to develop skills that are essential in all disciplines: making observations, developing and testing hypotheses, reaching conclusions based on the available data, recognizing and acknowledging uncertainty in scientific data and scientific conclusions, and communicating your results to others. The context for understanding global climate change today lies in the records of Earth’s past, as preserved in archives such as sediments and sedimentary rocks on land and on the seafloor, as well as glacial ice, corals, speleothems, and tree rings. These archives have been studied for decades by geoscientists and paleoclimatologists. Much like detectives, these researchers work to reconstruct what happened in the past, as well as when and how it happened, based on the often-incomplete and indirect records of those events preserved in these archives. This book uses guided-inquiry to build your knowledge of foundational concepts needed to interpret such archives. Foundational concepts include: interpreting the environmental meaning of sediment composition, determining ages of geologic materials and events (supported by a new section on radiometric dating), and understanding the role of CO2 in Earth’s climate system, among others. Next, this book provides the opportunity for you to apply your foundational knowledge to a collection of paleoclimate case studies. The case studies consider: long-term climate trends, climate cycles, major and/or abrupt episodes of global climate change, and polar paleoclimates. New sections on sea level change in the past and future, climate change and life, and climate change and civilization expand the book’s examination of the causes and effects of Earth’s climate history. In using this book, we hope you gain new knowledge, new skills, and greater confidence in making sense of the causes and consequences of climate change. Our goal is that science becomes more accessible to you. Enjoy the challenge and the reward of working with scientific data and results! Reconstructing Earth’s Climate History, Second Edition, is an essential purchase for geoscience students at a variety of levels studying paleoclimatology, paleoceanography, oceanography, historical geology, global change, Quaternary science and Earth-system science.

The question of whether the earth's climate is changing in some significant human-induced way remains a matter of much debate. But the fact that climate is variable over time is well known. These two elements of climatic uncertainty affect water resources planning and management in the American West. Managing Water Resources in the West Under Conditions of Climate Uncertainty examines the scientific basis for predictions of climate change, the implications of climate uncertainty for water resources management, and the management options available for responding to climate variability and potential climate change.