Download or read book Reconstructing Glacier Evolution Using a Flowline Model written by Julia Eis and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glacier mass change is one of the main causes of past sea-level rise and glaciers will continue to be a major contributor in the 21st century. Despite their importance, knowledge about past glacier mass changes is strongly limited. Whereas detailed observations exist for a very small number of glaciers, empirical evidence on a regional or global scale is largely incomplete, both spatially and temporally. The reconstruction of past glacier states by automatic numerical methods could fill this lack of information. Such reconstructions play a major role to fully understand the sea-level budget. They are crucial in terms of model validation, can be used to detect and improve model uncertainties, and they increase the confidence in projections. A framework, which provides all requirements to obtain these reconstructions is the Open Global Glacier Model (OGGM). It is an open source numerical glacier model, that is globally applicable by modeling each glacier individually, and developed for the simulation of glacier changes. However, providing realistic glacier changes with OGGM during the course of the entire 20th century requires an adequate initial state for every of the ∼200.000 glaciers worldwide. To find these initial states, this thesis presents an approach using the only given information for every individual glacier: past climate information and present-day geometry. Synthetic experiments showed that even under perfectly known but incomplete boundary conditions, this is an ill-posed inverse problem, leading to non-unique solutions. The synthetic environment enables the determination of the accuracy of the method, but on the other hand comparisons with real world observations are not possible. In order to facilitate such comparisons, a glacier-specific calibration of the mass balance model is introduced. This procedure finally allows for a validation.
Download or read book Glacier Evolution in a Changing World written by Danilo Godone and published by BoD – Books on Demand. This book was released on 2017-10-04 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glaciers have always played an important role in human history, and currently, they are carefully observed as climate change sentinels. Glacier melt rate is increasing, and its mass balance is continuously negative. This issue deserves accurate and in-depth studies in order to, adequately, monitor its state. This circumstance in fact endangers the water supply, affecting human settlements but also creating new environments allowing the colonization by pioneer communities and the formation of new landscapes. This book is subdivided into two main sections in order to deal with the two topics of worldwide research on glaciers and ecology in glacial environments. In the first one "Glaciers in the World," several reviews and studies are collected. It is an overview of glaciers, their state, and research carried out in different continents and contexts. The second section "Glacial Ecosystems" focuses, on the other hand, on glacier environments and ecological researches.
Download or read book Numerical Modelling written by Peep Miidla and published by BoD – Books on Demand. This book was released on 2012-03-23 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book demonstrates applications and case studies performed by experts for professionals and students in the field of technology, engineering, materials, decision making management and other industries in which mathematical modelling plays a role. Each chapter discusses an example and these are ranging from well-known standards to novelty applications. Models are developed and analysed in details, authors carefully consider the procedure for constructing a mathematical replacement of phenomenon under consideration. For most of the cases this leads to the partial differential equations, for the solution of which numerical methods are necessary to use. The term Model is mainly understood as an ensemble of equations which describe the variables and interrelations of a physical system or process. Developments in computer technology and related software have provided numerous tools of increasing power for specialists in mathematical modelling. One finds a variety of these used to obtain the numerical results of the book.
Download or read book Glaciers and Glaciation 2nd edition written by Douglas Benn and published by Routledge. This book was released on 2014-02-04 with total page 817 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glaciers and Glaciation is the classic textbook for all students of glaciation. Stimulating and accessible, it has established a reputation as a comprehensive and essential resource. In this new edition, the text, references and illustrations have been thoroughly updated to give today's reader an up-to-the minute overview of the nature, origin and behaviour of glaciers and the geological and geomorphological evidence for their past history on earth. The first part of the book investigates the processes involved in forming glacier ice, the nature of glacier-climate relationships, the mechanisms of glacier flow and the interactions of glaciers with other natural systems such as rivers, lakes and oceans. In the second part, the emphasis moves to landforms and sediment, the interpretation of the earth's glacial legacy and the reconstruction of glacial depositional environments and palaeoglaciology.
Download or read book Past to Future and Land to Sea Constraining Global Glacier Models by Observations and Exploring Ice ocean Interactions written by Jan-Hendrik Malles and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glacier mass loss is an iconic process induced by anthropogenic climate change. It threatens human livelihood at coasts affected by the rising sea level and in glacierized hydrological basins where the glacial runoff is essential for water availability. Moreover, as glacier mass loss adds large amounts of freshwater to the oceans, it might alter ocean circulation in a way that affects marine ecosystems and the climate system. Only recently, satellite-data processing revealed mass changes on an individual glacier level (outside the large ice sheets), but only for the last two decades. Glacier mass change observations become increasingly sparse going back in time. Therefore, the glaciers' past contribution to global mean sea level rise can only be reconstructed using numerical models. Since glacier mass change will continue during this century, it is vital to understand how this will affect global mean sea level, ocean circulation, and regional hydrology. Again, this is only possible using numerical models. Hence, it is essential to improve these models by incorporating previously neglected processes of glacier mass change into them, mainly in the form of parametrizations, and by constraining them using observations. Moreover, it is crucial to understand the uncertainties of results produced by numerical models, as they can never fully represent the natural world, which also hinges on the amount and quality of observational data. This work will tackle aspects of three issues in numerically modeling glacier mass changes: past glacier mass change reconstructions' uncertainties, future mass change projections' uncertainties, specifically regarding marine-terminating glaciers, and ice-ocean interactions in the northern hemisphere outside the Greenland ice sheet. All three issues are relevant in addressing the question of how glaciers respond to changes in their mass balance due to climatic changes and what consequences such changes have for the Earth system and, ultimately, human livelihood. It is found that the further outside the glaciological and meteorological observations' spatial and temporal domain a numerical model is applied, the more uncertain reconstructed glacier mass changes become. Similarly, one primary source of uncertainty in future glacier mass change projections is the difference in climate models' outputs of near-surface temperatures and precipitation. More accurately describing marine-terminating glacier dynamics and considering volume changes below sea level reduces estimates of future glacier contribution to global mean sea level rise systematically. However, significant uncertainties due to uncertainty about appropriate values for parameters involved in modeling (marine-terminating) glaciers' dynamics are detected. Concerning ice-ocean interactions, it was found that including the freshwater input from glacier mass loss in the northern hemisphere (outside the Greenland ice sheet) in an ocean general circulation model significantly impacts the simulated high-latitude ocean circulation. Finally, a first estimate of the ice mass glaciers lose due to melting directly into the ocean was produced.
Download or read book Past and Future Evolution of French Alpine Glaciers in a Changing Climate written by Jordi Bolibar Navarro and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The European Alps are among the most affected regions in the world by climate change, displaying some of the strongest glacier retreat rates. Long-term interactions between society, mountain ecosystems and glaciers in the region raise important questions on the future evolution of glaciers and their derived environmental and socioeconomical impacts. In order to correctly assess the regional response of glaciers in the French Alps to climate change, there is a need for adequate modelling tools. In this work, we explore new ways to tackle both glacier evolution and glacio-hydrological modelling at a regional scale. Glacier evolution modelling has traditionally been performed using empirical or physical approaches, which are becoming increasingly challenging to optimize with the ever growing amount of available data. Here, we present, to our knowledge, the first effort ever to apply deep learning (i.e. deep artificial neural networks) to simulate the evolution of glaciers. Since both the climate and glacier systems are highly nonlinear, traditional linear mass balance models offer a limited representation of climate-glacier interactions. We show how important nonlinearities in glacier mass balance are captured by deep learning, substantially improving model performance over linear methods.This novel method was first applied in a study to reconstruct annual mass balance changes for all glaciers in the French Alps for the 1967-2015 period. Using climate reanalyses, topographical data and glacier inventories, we demonstrate how such an approach can be successfully used to reconstruct large-scale mass balance changes from observations. This study also offered new insights on how glaciers evolved in the French Alps during the last half century, confirming the rather neutral observed mass balance rates in the 1980s and displaying a well-marked acceleration in mass loss from the 2000s onwards. Important differences between regions are found, with the Mont-Blanc massif presenting the lowest mass loss and the Chablais being the most affected one. Secondly, we applied this modelling framework to simulate the future evolution of all glaciers in the region under multiple (N=29) climate change scenarios. Our estimates indicate that most ice volume in the region will be lost by the end of the 21st century independently from future climate scenarios. We predict average glacier volume losses of 74%, 80% and 88% under RCP 2.6 (n=3), RCP 4.5 (n=13) and RCP 8.5 (n=13), respectively. By the end of the 21st century the French Alps will be largely ice-free, with glaciers only remaining in the Mont-Blanc and Pelvoux massifs.
Download or read book Glaciation written by David J. A. Evans and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: David Evans introduces glaciers and ice sheets as systems, discussing the processes that shape them, and their impacts on our planet in terms of erosional and depositional processes. He explains how we can use this knowledge in reconstructing glaciers and ice sheets of the past, and discusses the impacts on glaciers of climate change.
Download or read book Reconstructing Mass Balance of South Cascade Glacier Using Tree ring Records written by Kailey Marcinkowski and published by . This book was released on 2012 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mountain hemlock growth chronologies were used to reconstruct the mass balance of South Cascade Glacier, an alpine glacier in the North Cascade Range of Washington State (USA). The net balance reconstruction spans 350 years, from 1659 to 2009. Summer and winter balances were also reconstructed for 1346-2009 and 1615-2009, respectively. Relationships between mass balance and winter precipitation, temperature, the Pacific Decadal Oscillation index, and the El Niño Southern Oscillation index suggest that these climatic variables and indices influence glacier balance fluctuations at various temporal scales. Periods of above-average net, summer, and winter mass balance occurred mainly in 1790-1800, 1810-1820, 1845-1860, 1865-1890, and 1970-1990. Above- and below-average reconstructed mass balances at South Cascade Glacier were concurrent with similar periods from other glacier balance reconstructions and moraine dates in the Pacific Northwest region of North America. Agreement among these records suggests that changes in South Cascade Glacier mass balance are good indicators of regional balance fluctuations, and glaciers in the Pacific Northwest are responding similarly to regional external climate forcings. The current rate of decline, from 2000 to 2009, in the reconstructed mass balance record has been faster than any other decline in a century. This decreasing trend is projected to continue in accordance with increasing temperatures, and will likely affect glacier-influenced water resources in the Pacific Northwest.
Download or read book Ice Surface Reconstruction and Energy Balance Modeling of Alpine Glaciers written by Colin Daniel Poellot and published by . This book was released on 2000 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glacial deposits on San Francisco Mountain, Arizona, were mapped in order to provide constraints on ice extents in separate valleys for late Pleistocene glacial events. Qualitative and semi-quantitative relative dating methods were employed in order to correlate moraines between drainages and to provide a basis for distinguishing between separate glacial events within drainages. Morphologic and surficial weathering characteristics that were measured include degree of moraine dissection, moraine crestal width, moraine inner and outer slope angle, surface boulder frequency, percentage of weathered surface boulders, percentage of pitted surface boulders, maximum pit depth, and percentage of split boulders. Results of the relative dating study support past studies that differentiate 3 separate drift sequences on the mountain. Five separate glacier surfaces were reconstructed from the mapped moraine crests, four for the most recent glaciation, and one for the intermediate glacial event. ELAs from the reconstructed glaciers range from 3140 to 3400 meters. In addition, a numerical model was developed that uses an energy balance approach to calculate annual ablation over a glacier surface. The energy balance approach used in the model was designed to allow the model to test sensitivity of former glaciers to changes in temperature or precipitation. Required model inputs include a two-dimensional elevation map of the glacier surface and surrounding topography, as well as climate records that include daily values of air temperature, wind speed, precipitation, atmospheric vapor pressure, incoming shortwave radiation, and incoming longwave radiation. Model outputs include the net specific balance and equilibrium line altitude of the glacier. Model simulations of mass balance are compared with observed data from the 1990 ablation season at Haut Glacier d'Arolla, Valais, Switzerland. Calculated ablation values closely match observed values, thereby supporting the validity of the model. A preliminary model run was also accomplished for the 5 Pleistocene glaciers reconstructed on San Francisco Mountain, Arizona, using output from a regional climate model as input. The model delivers a glacier that is nearly in mass balance for one of the reconstructions.
Download or read book Ice Composition and Glacier Dynamics written by Roland A. Souchez and published by Springer. This book was released on 2012-11-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ice composition has until now been mostly used for reconstructing the environment of the past. A great research effort is made today to model the climate system in which the ice cover at the earth sur face plays a prominent role. To obtain a correct model of the ice sheets, due attention must be paid to the physical processes operating at the interfaces, i. e. the boundary conditions. The idea behind the title of this book is that the study of ice composition can shed some light on the various processes operating at the ice bedrock and ice-ocean interfaces and more generally on glacier dy namics. The book is not intended as a treatise on some specialized topic of glaciology. It is mainly the product of the experience of the two authors gained over several years research on the subject. The two authors are both members of the same university department and personal friends. The book was prepared in the following way. After a first draft of the complete book had been written by the first author, it was put in the hands of the second. The final version sent to the publishers is therefore the result of ex tended discussion, while at the same time preserving the unity of style that would have been lost had the two authors written selected chapters of the book individually. The book is organized into two distinct parts.
Download or read book Analysis of a Paleoglacier Reconstruction Model for Valley Glaciers of the Wind River Range Wyoming written by Taylor Rae Garton and published by . This book was released on 2019 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Remote Sensing Technology and the Three Poles written by Manish Pandey and published by John Wiley & Sons. This book was released on 2022-12-12 with total page 485 pages. Available in PDF, EPUB and Kindle. Book excerpt: ADVANCES IN REMOTE SENSING TECHNOLOGY AND THE THREE POLES Covers recent advances in remote sensing technology applied to the “Three Poles”, a concept encompassing the Arctic, Antarctica, and the Himalayas Advances in Remote Sensing Technology and the Three Poles is a multidisciplinary approach studying the lithosphere, hydrosphere (encompassing both limnosphere, and oceanosphere), atmosphere, biosphere, and anthroposphere, of the Arctic, the Antarctic and the Himalayas. The drastic effects of climate change on polar environments bring to the fore the often subtle links between climate change and processes in the hydrosphere, biosphere, and lithosphere, while unanswered questions of the polar regions will help plan and formulate future research projects. Sample topics covered in the work include: Terrestrial net primary production of the Arctic and modeling of Arctic landform evolution Glaciers and glacial environments, including a geological, geophysical, and geospatial survey of Himalayan glaciers Sea ice dynamics in the Antarctic region under a changing climate, the Quaternary geology and geomorphology of Antarctica Continuous satellite missions, data availability, and the nature of future satellite missions, including scientific data sharing policies in different countries Software, tools, models, and remote sensing technology for investigating polar and other environments For postgraduates and researchers working in remote sensing, photogrammetry, and landscape evolution modeling, Advances in Remote Sensing Technology and the Three Poles is a crucial resource for understanding current technological capabilities in the field along with the latest scientific research that has been conducted in polar areas.
Download or read book Glaciers and Climate Change written by J. Oerlemans and published by CRC Press. This book was released on 2001-01-01 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text brings together meteorology and the theory of glacier flow, providing a fundamental understanding of how glaciers respond to climate change. Attention is paid to the microclimate of glaciers and the physical processes regulating the exchange of energy and mass between glacier surface and atmosphere. Simple analytical and numerical models are used to: · investigate glaciers sensitivity to climate change · estimate response times · make an interpretation of historical glacier records · assess the contribution of glacier melt to sea-level rise Modern developments in glacier research, including satellite measurements are discussed in detail, making this a valuable reference source.
Download or read book Global Land Ice Measurements from Space written by Jeffrey S. Kargel and published by Springer. This book was released on 2014-07-08 with total page 936 pages. Available in PDF, EPUB and Kindle. Book excerpt: An international team of over 150 experts provide up-to-date satellite imaging and quantitative analysis of the state and dynamics of the glaciers around the world, and they provide an in-depth review of analysis methodologies. Includes an e-published supplement. Global Land Ice Measurements from Space - Satellite Multispectral Imaging of Glaciers (GLIMS book for short) is the leading state-of-the-art technical and interpretive presentation of satellite image data and analysis of the changing state of the world's glaciers. The book is the most definitive, comprehensive product of a global glacier remote sensing consortium, Global Land Ice Measurements from Space (GLIMS, http://www.glims.org). With 33 chapters and a companion e-supplement, the world's foremost experts in satellite image analysis of glaciers analyze the current state and recent and possible future changes of glaciers across the globe and interpret these findings for policy planners. Climate change is with us for some time to come, and its impacts are being felt by the world's population. The GLIMS Book, to be released about the same time as the IPCC's 5th Assessment report on global climate warming, buttresses and adds rich details and authority to the global change community's understanding of climate change impacts on the cryosphere. This will be a definitive and technically complete reference for experts and students examining the responses of glaciers to climate change. World experts demonstrate that glaciers are changing in response to the ongoing climatic upheaval in addition to other factors that pertain to the circumstances of individual glaciers. The global mosaic of glacier changes is documented by quantitative analyses and are placed into a perspective of causative factors. Starting with a Foreword, Preface, and Introduction, the GLIMS book gives the rationale for and history of glacier monitoring and satellite data analysis. It includes a comprehensive set of six "how-to" methodology chapters, twenty-five chapters detailing regional glacier state and dynamical changes, and an in-depth summary and interpretation chapter placing the observed glacier changes into a global context of the coupled atmosphere-land-ocean system. An accompanying e-supplement will include oversize imagery and other other highly visual renderings of scientific data.
Download or read book The Physics of Glaciers written by W. S. B. Paterson and published by Elsevier. This book was released on 2016-10-27 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: This updated and expanded version of the second edition explains the physical principles underlying the behaviour of glaciers and ice sheets. The text has been revised in order to keep pace with the extensive developments which have occurred since 1981. A new chapter, of major interest, concentrates on the deformation of subglacial till. The book concludes with a chapter on information regarding past climate and atmospheric composition obtainable from ice cores.
Download or read book Untangling the Quaternary Period written by Richard B. Waitt and published by Geological Society of America. This book was released on 2021-04-20 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This volume brings together nineteen papers of interdisciplinary Quaternary science honoring Stephen Porter. Special Paper 548 features papers from six continents, on wide-ranging topics including glaciation, paleoecology, landscape evolution, megafloods, and loess. The topical and geographical range of the papers, as well as their interdisciplinary nature, honor Porter's distinct approach to Quaternary science and leadership that influence the field to this day"--
Download or read book Drift Exploration in Glaciated Terrain written by Geological Society of London and published by Geological Society of London. This book was released on 2001 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume describes the use of till geochemical and indicator mineral methods for mineral exploration in the glaciated terrain of Canada. The principles and examples described in this volume will have direct applications for exploration companies looking for diamonds, precious and base metals and uranium in glaciated parts of North America, northern Europe and Asia and mountainous regions of South America.
