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Brenner considers the impacts of this paper, in light of subsequent Maya paleoclimate/paleoenvironmental studies published in the last four decades. This special issue considers physical geography in the Maya Lowlands, a tropical, mostly low-lying carbonate platform in the Yucatan Peninsula of Mexico, Belize, Guatemala, and parts of Honduras and El Salvador. Indeed, much of what we know about this region's environments (i.e., its physical geography and paleoenvironment) derives from work sponsored by archaeology projects funded by the National Geographic Society, the National Science Foundation, the UK Overseas Development Agency, and many other entities, including early support from the Carnegie Institution. Garrison and colleagues overview the use of lidar survey methods in the Maya region, highlighting how Maya archaeology has aided progress in physical geography. [Extracted from the article]

Sound is produced by many geomorphic and hydrological processes, such as rockfalls and landslides, ocean waves, fluvial flood flows and collisions among moving bedload clasts. In these and other areas of study, acoustic methods have found useful application to detect and quantify the operation of important landscape processes. In some, such as the recording of river discharge, the occurrence of rare events such as exfoliation or the presence and movement of dust devils (willy-willies), the use of acoustic methods is still in a relatively early stage of development and testing. The use of acoustic methods in the recording of rainfall occurrence and intensity is also developing and has the capacity to yield data with higher temporal resolution than can be achieved using conventional rain gauges. Novel acoustic methods include the analysis of the sound recorded by security cameras, which potentially form a vast network of observing stations. The frequencies of sound generated by land-surface processes include audible sound, ultrasound and infrasound at frequencies below the human hearing range. All appear to provide opportunities for further development of useful research tools and methodologies. [ABSTRACT FROM AUTHOR]

Thus, an accurate representation of landform in a given area plays an essential role in revealing the formation mechanisms and indicating the landform evolution process. It presents the most recent and updated global set of landscape variables, describing the spatial properties (dimensions, slope, curvature, relief) of landforms (morphometry) for the whole globe. The dataset comprises 26 layers, organized into three categories of metrics, able to describe the rate of change (Figure 1(a), (d)), the heterogeneity (Figure 1(b), (d)) and geomorphology (Figure 1(c), (e)) of the landscape globally, for a variety of environments. [Extracted from the article]

Physical geography is a process, conducted by people, of integration and synthesis of ideas and observations to advance scientific understanding of Earth's surface and atmosphere and to apply this knowledge to the greater good of the planet and its people. Therefore, physical geography matters; that is, physical geography makes a difference to people and contributes to environmental decision making at various scales. Based upon presentations and discussion at the 2019 AAG Annual Meeting (see editorial above in this issue), we provide here a historical perspective and distillation of how and why, in our opinions, physical geography matters. Although we provide several specific examples, these represent only a small portion of the large body of excellent and relevant physical geography research. [ABSTRACT FROM AUTHOR]

Physical geography focuses on the Earth surface system and is dedicated to revealing how people affect the environment and how the environment reacts to people. Based on its characteristic spatial cognitive perspective, the inductive–deductive combined approach, and the comprehensive research paradigm that integrates multiple elements, processes, and scales, physical geography always provides an important scientific basis for understanding human–nature interactions and solving sustainable development issues in different eras. Putting theory into practice, physical geography plays a pivotal role in realizing the UN Sustainable Development Goals and China's goal of ecological civilization. At present, China is in a stage of rapid socio-economic development and global conditions are changing more quickly than ever. Based on its disciplinary characteristics and traditional advantages, physical geography in China should always develop around social needs and play an increasing role in resource- and environment-related policies and outreach. Future development of physical geography as a discipline in China is expected, taking spatial cognition as the basic perspective and human–nature interaction as the core content, along with the combination of deductive and inductive approaches and the strengthening of interregional integration, all under the goal of sustainability. Considering the shared environmental challenges and the complexity of interconnections between countries in the context of globalization, the academic exploration and practice of physical geography in China have been providing scientific support for the sustainable development of China and beyond. [ABSTRACT FROM AUTHOR]

The recent publication of several books on the history and ecology of beavers (Castor canadensis and Castor fiber) illustrates a renewed interest in the construction activities of beavers and their impacts on landscapes. Over one hundred years ago, two popular books on these same topics were published, In Beaver World and The Romance of the Beaver. These books, their authors, and their legacies can still inform today's readers interested in beavers, ecosystem engineering, and zoogeomorphology. [ABSTRACT FROM AUTHOR]

Past studies of archaeological bog finds, such as bog bodies, wooden trackways and a wide variety of other materials, are characterized by a strong focus on material culture. Their original environmental and cultural context has received far less attention. This paper centres on the original landscape setting of bog bodies. Interdisciplinary reconstructions of the physical and cultural landscape at the time of deposition can lead to significant new and more detailed insights into the context and meaning of this remarkable phenomenon. We aim to show the value of such interdisciplinary research by reconstructing the original physical and cultural landscape setting of the most iconic bog body of The Netherlands: Yde Girl. This approximately 16-year-old girl was killed about 2000 years ago and deposited in a bog south of the modern-day village of Yde (province of Drenthe). Our interdisciplinary research team used a combination of research methods from physical geography, geomorphology, palynology and archaeology to analyse both the site itself and its wider environment. This kind of integrated, detailed landscape research on bog bodies has hardly been done yet. We expect that our research design, methodology and results may also be applied in future research of other bog bodies. Furthermore, they may inspire research on other types of archaeological find categories from peatlands. [ABSTRACT FROM AUTHOR]

In this introduction to the special issue on necrogeography and physical geography, a focus on landforms and landscapes is presented and applied to subdisciplinary areas, including geomorphology, climatology, biogeography, and soil science. The primary aim is to present past directions taken in the field by physical geographers and provide further areas for their potential engagement. The seven papers contained in this special issue are lastly conveyed in terms of their contribution to necrogeography as an applied physical geography in cemeteries, although not exclusively. [ABSTRACT FROM AUTHOR]

Even as it remains an informal term defining the emergence of humans as a force transforming Earth as a system, the Anthropocene is stimulating novel research and discussion across the academy and well beyond. While geography has always been deeply connected with the coupled human--environment paradigm, physical geographer's embrace of the Anthropocene still appears lukewarm at best. While there are good reasons to hesitate, including the fact that the Anthropocene is not yet, and might never be, formalized in the Geologic Time Scale, physical geographers have much to gain by embracing what is rapidly becoming the most influential scholarly discussion on human--environmental relations in a generation. This editorial was commissioned for the author's debut as Contributing Editor of Progress in Physical Geography. [ABSTRACT FROM AUTHOR]

One of the most prominent American geomorphologists, Neil E. Salisbury, passed away in May 2015. This paper examines his legacy in geomorphology over the course of his career, and hopefully will be seen as honoring his memory. [ABSTRACT FROM AUTHOR]

The geomorphic relationships known as hydraulic geometry (HG) were first introduced by Leopold and Maddock in 1953, and their application remains critically important for assessing water resources the world over. The practical utility of HG for discharge monitoring, habitat studies, and understanding geomorphic change over time is unquestioned, but its elevation beyond empirically observed relationship to physical principle is not complete, despite universal acceptance of its existence. This review summarizes six decades of HG research while surveying rational, extremal, and empirical attempts to derive HG’s underlying physical principles. In addition, so called non-Leopoldian forms of HG are discussed, expanding HG beyond its original construction to examine a range of research that invokes HG in novel ways. The recent discovery of at-many-stations hydraulic geometry (AMHG) is also discussed in the context of previous HG literature. Finally, some common themes linking disparate HG research communities are described in conjunction with suggestions for possible new directions for HG research in the future. [ABSTRACT FROM PUBLISHER]

The chapter on local-scale geomorphology (Chapter 4) includes weathering (mechanical, chemical, influence of climate), slope and mass-movement/flow, and fluvial systems. Introducing Geomorphology, 2nd ed. Adrian Harvey's I Introducing Geomorphology i is not, as the author points out, a textbook per se, but rather an introduction to the science of geomorphology. [Extracted from the article]

This editorial is the product of the Progress in Physical Geography lecture at the April 2013 meeting of the Association of American Geographers. The paper was presented by George Malanson, the North American Editor, and the co-authors presented critiques based on a draft. Subsequently, the manuscript was developed and revised based on discussion at the meeting and additional exchange among the co-authors. [ABSTRACT FROM AUTHOR]

Isaiah Bowman’s book Forest Physiography (1911), subtitled Physiography of the United States and Principles of Soils in Relation to Forestry, was the first regional physiography text in the USA. This paper briefly describes Bowman’s background, the writing of the text, and its impact and legacy. [ABSTRACT FROM PUBLISHER]

Soil moisture is a critical component of the earth system and plays an integrative role among the various subfields of physical geography. This paper highlights not just how soil moisture affects atmospheric, geomorphic, hydrologic, and biologic processes but that it lies at the intersection of these areas of scientific inquiry. Soil moisture impacts earth surface processes in such a way that it creates an obvious synergistic relationship among the various subfields of physical geography. The dispersive and cohesive properties of soil moisture also make it an important variable in regional and microclimatic analyses, landscape denudation and change through weathering, runoff generation and partitioning, mass wasting, and sediment transport. Thus, this paper serves as a call to use research in soil moisture as an integrative and unifying theme in physical geography. [ABSTRACT FROM AUTHOR]

The field of tectonic geomorphology is in a state of tension. The widespread availability of high-quality, high-resolution digital topographic data encourages the development of simple morphological 'tools' which can be used to deduce recent tectonic evolution. Meanwhile, process geomorphologists recognize that current models have a significant empirical basis, and lack insight into the underlying physics of erosion processes. Most tectonic geomorphology research is concerned with rivers, but glaciers, debris flows and hillslope processes also play a key role in hypotheses linking climate to tectonics, via surface processes, while submarine geomorphology has barely been investigated in a tectonic context. Studies combining field data collection, exposure, burial and low-temperature thermochronologic dating, digital topographic analysis, laboratory experiments and numerical models are successfully incorporating physics into geomorphic process 'laws', and demonstrating key tectonic geomorphology hypotheses. The approaches required for further progress have been outlined, but many exciting challenges remain. [ABSTRACT FROM AUTHOR]

Earth system science (ESS) is an approach to: 'obtain a scientific understanding of the entire Earth system on a global scale by describing how its component parts and their interactions have evolved, how they function, and how they may be expected to continue to evolve on all timescales' (Bretherton, 1998). The aim of this review is to introduce some key examples showing the role of Earth surface processes, the traditional subject of geomorphology, within the interacting Earth system. The paper considers three examples of environmental systems in which geomorphology plays a key role: (1) links between topography, tectonics, and atmospheric circulation; (2) links between geomorphic processes and biogeochemical cycles; and (3) links between biological processes and the Earth's surface. Key research needs are discussed, including the requirement for better opportunities for interdisciplinary collaboration, clearer mathematical frameworks for Earth system models, and more sophisticated interaction between natural and social scientists. [ABSTRACT FROM AUTHOR]

Rivers self-organize their pattern/planform through feedbacks between bars, channels, floodplain and vegetation, which emerge as a result of the basic spatial sorting process of wash load sediment and bed sediment. The balance between floodplain formation and destruction determines the width and pattern of channels. Floodplain structure affects the style and rate of channel avulsion once aggradation takes place. Downstream fining of bed sediment and the sediment balance of fines in the pores of the bed sediment provide the 'template' or sediment boundary conditions, from which sorting at smaller scales leads to the formation of distinct channel patterns. Bar patterns provide the template of bank erosion and formation as well as the dynamics of the channel network through bifurcation destabilization. However, so far we have been unable to obtain dynamic meandering in laboratory experiments and in physics-based models that can also produce braiding, which reflects our lack of understanding of what causes the different river patterns. [ABSTRACT FROM AUTHOR]

Modern geomorphology was founded in the nineteenth century as an exercise of historical interpretation of landscapes. After the mid-twentieth century it dominantly became a quest to understand the processes by which landscapes are modified. This focused attention on the measurement of sediment fluxes on synoptic timescales and on a reductionist, Newtonian programme of construction of low-order theories about those fluxes, largely imported from engineering science. The period also saw the emergence of an applied geomorphology. Toward the end of the twentieth century the subject was dramatically transformed by improved technologies for remote sensing and surveying of Earth's surface, the advent of personal computation and of large-scale computation, and important developments of absolute dating techniques. These technical innovations in turn promoted recognition of geomorphology as a 'system science' and facilitated the reintegration of tectonics into geomorphology, opening the way for a renewed consideration of the history of the landscape. Finally, increasing recognition of the dominance of human agency in contemporary modification of Earth's terrestrial surface has become a significant theme. Important influences on the continuing development of the subject will include the search for physically sound laws for material fluxes; reconciling geomorphological information and process representations across spatial and temporal scales, in both observation and theory; comprehending complexity in geomorphological processes and landform histories; incorporating the geomorphological role of living organisms, particularly micro-organisms; understanding the role of climate in geomorphology, both in the contemporary changing climate and in the long term; and fully admitting the now dominant role of humans as geomorphic agents. Geomorphology is simultaneously developing in diverse directions: on one hand, it is becoming a more rigorous geophysical science - a significant part of a larger earth science discipline; on another, it is becoming more concerned with human social and economic values, with environmental change, conservation ethics, with the human impact on environment, and with issues of social justice and equity. [ABSTRACT FROM AUTHOR]

In this progress report we review recent work which has investigated the process of glaciohydraulic supercooling and its significance for a range of glaciological and geological phenomena. Since our last report (Knight and Cook, 2008), glaciohydraulic supercooling has been identified in new locations and under hitherto unrecognized conditions, both for modern and formerly glaciated environments. Recent work has examined the record of supercooling preserved in the landform and sediment record, within tunnel valleys and in sequences of melt-out till. We suggest that supercooling may also have important implications for glacier dynamics because of the role it may play in controlling the geometry of subglacial over deepenings, which in turn acts as a control on the dynamics of tidewater glaciers. Despite these numerous recent scientific advances, there remains a need to critically evaluate the importance of supercooling for the various aspects of sediment entrainment and flux, glacial geomorphology and ice dynamics with which it has become associated. We illustrate how collaboration with researchers in other branches of cryospheric science, such as sea-ice scientists, might shed new light on the significance of supercooling within these various aspects of glacier science. [ABSTRACT FROM AUTHOR]

Remotely sensed imagery has been used extensively in geomorphology since the availability of early Landsat data, with its value measurable by the extent to which it can meet the investigative requirements of geomorphologists. Geomorphology focuses upon landform description/classification, process characterization and the association between landforms and processes, while remote sensing is able to provide information on the location/distribution of landforms, surface/subsurface composition and surface elevation. The current context for the application of remote sensing in geomorphology is presented with a particular focus upon the impact of new technologies, in particular: (1) the wide availability of digital elevation models; and (2) the introduction of hyperspectral imaging, radiometrics and electromagnetics. Remote sensing is also beginning to offer capacity in terms of close-range (<200 m) techniques for very highresolution imaging. This paper reviews the primary sources for DEMs from satellite and airborne platforms, as well as briefly reviewing more traditional multispectral scanners, and radiometric and electromagnetic systems. Examples of the applications of these techniques are summarized and presented within the context of geomorphometric analysis and spectral modelling. Finally, the wider issues of access to geographic information and data distribution are discussed. [ABSTRACT FROM AUTHOR]

In recent decades views of change, disturbance, response, and recovery in geomorphology have expanded considerably. Conceptual frameworks emphasizing single-path, single-outcome trajectories of change have been supplemented - not replaced - by multi-path, multi-outcome perspectives. Geomorphology has also seen a transition from the idea of normative standards such as characteristic, (steady-state) equilibrium, zonal, and mature forms to the recognition that some systems may have multiple potential characteristic or equilibrium forms - and that some may have no particular normative state at all. These trends are not presented as a replacement of outmoded ideas, but rather as a broadening of approaches. The single-path single-outcome frameworks can generally be viewed as special cases of the broader pluralistic analytical structures. In this context, two perspectives - an adaptation of White's hazards matrix, and the landscape sensitivity concept - are suggested which lend themselves to studies of recent and contemporary changes in earth surface systems. These perspectives can be synthesized into a framework for the assessment of geomorphic changes and responses based on the 'four Rs': response (reaction and relaxation times), resistance (relative to the drivers of change), resilience (recovery ability, based on dynamical stability), and recursion (positive and/or negative feedbacks). [ABSTRACT FROM AUTHOR]

This review highlights recent work in coastal geomorphology that challenges existing wisdom, breaks new ground or contributes in some way to wider principles. Sediment transport by currents and by waves remains a major focus of coastal process geomorphology, and the contribution of this work to our appreciation of landform dynamics is particularly evident at the beach scale. Reconstructive studies over Holocene to historical timescales are yielding new insights into the adjustment of coastal sedimentary systems to progressive environmental forcing, high-magnitude events and human activities. Coastal geomorphology is currently buoyed by opportunities afforded by the implied threats of climate change and sea-level rise, and by the conceptual and technical challenges of predicting morphodynamic behaviour at the all-important 'engineering' scales. Of some concern is the lack of dialogue with other major strands of geomorphology. One of the main challenges, to create models capable of revealing emergent aspects of spatially distributed interactions between form and process, is common to all geomorphologists engaged with the meso-scale. Yet coastal specialists seem reluctant both to draw inspiration from and also to contribute ideas to what might be seen as a single, extremely broad, research front. More generally, there is little exchange of ideas or contribution to a shared intellectual endeavour. Coastal geomorphology is at the forefront of the discipline when it comes to the exploitation of new environmental instrumentation and remote sensing technologies. It can only be hoped that the plethora of high-resolution multitemporal data sets will contribute to the advance of geomorphological thinking rather than merely being used to constrain sediment budgets as a basis for the management of localized erosion problems. [ABSTRACT FROM AUTHOR]

The article focuses on some principles of S. C. Happ and colleagues regarding geomorphology, such as sediment budgets and valley sedimentation in Mississippi Coastal Plain. It explores the impact of human activity on land structure, the origins and pioneers of sediment budgets, and the scale and comprehensiveness of the study. It discusses the work of G. K. Gilbert that laid the foundations of human understanding to the phenomenon as well as the essential of colour and organic material in identifying presettlement soils.

The article discusses the progress of arid geomorphology and earth system science (ESS). It stated that the ESS is the study of the Earth as a single, integrated physical and socil system with human activity being brought in the core of the Earth system. The concept of ESS recognizes that pressing environmental problems require understanding of how components interface with the social, political and economic dimensions of human societies in the context of global environmental change. Moreover, the ESS response to external forcing depends on the nature of coupling between different landscape components.

The article discusses the significance of glaciohydraulic supercooling. It mentions that supercooling is placed in the relationship between climate and subglacial geomorphic processes. It also reveled that supercooling has increased its profile across the glacier science community. In addition, geographical research on glaciohydraulic supercooling and its impact on glaciological, geomorphological and sedimentological phenomena is likely to involve the use not only of field mapping but also of a range of technique.

Although natural selection operates at the gene or individual level, a number of proposals, hypotheses and theories exist postulating the evolution of entities such as ecosystems, and indeed the entire biosphere. Further, there exist theories of evolution that are based not on the relative advantages (be they competitive or mutualistic) conferred on individuals, populations, or taxa, but on community, ecosystem, or biosphere-level goal functions, typically related to productivity criteria. A key question is why nature would seek to optimize energy flux or efficiency, biogeochemical cycling, or anything else. While development along some optimal pathway does occur, whether this is a rule, a tendency, or merely a possibility is not clear. This paper reviews theories of evolution and ecosystem development based explicitly or implicitly on goal functions. If the environment is conceptualized as a multidimensional resource space allocated among organisms, then only three assumptions are necessary for a developmental pathway toward increasing productivity: (1) higher rates of resource procurement and use are associated with ecological or selective advantages; (2) the environment is biologically saturated (or tending in that direction); and (3) the resource space is not contracting due to external abiotic forcings. This suggests that a tendency for evolution along a pathway toward maximum energy and/more matter fluxes, storages, transformations, or cycling does not require goal functions or natural selection operating at levels beyond the individual. Key research needs involve rigorous testing of these assumptions (particularly the first two), and the relative importance of, and relationships between, various notions of productivity. [ABSTRACT FROM AUTHOR]

Historical data and artifacts, as commonly used in historical geography, can provide powerful tools for dating geomorphological processes over the past century or more and applications can range from months to millennia. Investigations in geomorphology and environmental management can be greatly enhanced by the use of historical techniques. The approach is useful for tracing human-induced changes as well as for those occurring naturally. Several primary techniques are introduced in this essay. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the past, present and future research developments in arid geomorphology, a study of dry landforms, including their origin and evolution, and the processes that shape them. It highlights the certain pervasive, emerging or overarching themes in arid geomorphological research, with 'arid' defined broadly to include hyper-arid, semi-arid and dry-subhumid regions as well. It discusses various studies which provide significant technical and methodological developments that is relevant for the application to arid geomorphological investigations, resulting to significant advances in the ability to quantify rates of processes, and the frequency and timing of changes.

The analysis and interpretation of remote sensing data facilitates investigation of land surface complexity on large spatial scales. We introduce here a geometrically high-resolution data set provided by the airborne High Resolution Stereo Camera (HRSC-A). The sensor records digital multispectral and panchromatic stereo bands from which a very high-resolution ground elevation model can be produced. After introducing the basic principles of the HRSC technique and data, applications of HRSC data within the multidisciplinary Research Training Group 437 are presented. Applications include geomorphologic mapping, geomorphometric analysis, mapping of surficial grain-size distribution, rock glacier kinematic analysis, vegetation monitoring and three-dimensional landform visualization. A final evaluation of the HRSC data based on three years of multipurpose usage concludes this presentation. A combination of image and elevation data opens up various possibilities for visualization and three-dimensional analysis of the land surface, especially in geomorphology. Additionally, the multispectral imagery of the HRSC data has potential for land cover mapping and vegetation monitoring. We consider HRSC data a valuable source of high-resolution terrain information with high applicability in physical geography and earth system science. [ABSTRACT FROM AUTHOR]

The article presents Brian Sissons and his research with D. E. Smith and R. A. Cullingford on the "Lateglacial and Postglacial Shorelines in South-East Scotland" which was published in 1966 in the journal "Transactions of the Institute of British Geographers." Sissons and others described the Scotland's Lateglacial and Halocene relative sea-level change in the research. Likewise, they were able to provide and to summarize new geomorphological and stratigraphic data on various raised and buried shorelines.

The article comments on the book "Climatic Geomorphology," by Julius Budel. It is a translation of the German book from 1977 "Klima-geomorphologie," Berlin-Stuttgart: Gebruder Borntraeger. For a mathematically skilled and modelling-orientated present-day geomorphologist hungry for numerical values and increasingly sophisticated software, it would be tempting to dismiss the book altogether as a long outdated which did not stand the test of time and does not meet recent criteria for evaluation. It is, however, true that Büdel's book abounds in bold, authoritarian statements and its many sections suffer from an unnecessary either/or approach in which Budel was right and other people were wrong.

The article discusses issues related coastal geomorphology in the U.S. It should be noted that there continues to be a clear trend away from the centrality of geomorphology and geography. It even appears that coastal geomorphologists are no longer publishing in major geomorphology journals. There is little evidence to suggest that coastal geomorphology is making significant contributions to the broader theoretical framework of geomorphology. The author offers some commentary on the position of coastal geomorphology within Geomorphology and Physical Geography, based on the progress made over the last three years.

Over the past 10 to 15 years there has been a surge in interest in step-pool streams in fluvial geomorphological research. This reflects recognition of the geomorphic significance of step pools in high-gradient channels, and a growing interest in rivers in mountainous regions in general. This paper synthesizes the recent literature on step pools, with particular reference to theory construction and progress made over the past decade and a half. Four groups of contributions are identified. The first focuses on understanding morphological relations in order to seek causal mechanisms. The second emphasizes processes that result from the step-pool configuration. The third is a group of integrative studies that seek broader explanations for step-pool sequences. The fourth and growing body of literature applies what has been learned about step pools toward managing and restoring steep channels. We conclude by highlighting some future possible research directions toward gaining a complete explanation for step pools in stream channels. [ABSTRACT FROM AUTHOR]

Discusses the findings of various research on process-based fluvial geomorphology. Importance of fluvial geomorphology in characterizing the watershed; Determination of erosion processes and the evolution of landscape form; Problem of predicting the equilibrium alluvial channel form.

Contemporary knowledge on aeolian dune dynamics is reviewed to enable an appraisal of evolutionary mechanisms involved in linear dune stratigraphic sequence development. The degrees of depositional record retention in the dune structures are evaluated and the corollary applied to methods used in the interpretation of luminescence dating chronologies acquired from such sedimentary accumulations. It is demonstrated that morphogenetic aspects of dune development are an imperative element to invoke when carrying out palaeoenvironmental reconstruction using luminescence dating ages acquired from linear dune sequences. To help depict the role of dune morphogenesis, hypothetical scenarios that simulate the preservation of stratigraphical records in linear dune sequences are presented using two different theories that have been advanced to explain origin and development of linear dunes: bidirectional wind regime and helical roll vortices. It is illustrated that linear dune systems that evolve under bidirectional wind influence are intrinsically inefficient at preserving complete records of their depositional history and this places major constraints for palaeoenvironmental reconstruction using luminescence chronologies. When linear dunes develop under the influence of helical roll vortices, on the other hand, it is shown that the degree of sequence preservation would be higher. The possibility of lateral migration of linear dune structures is indicated to be an additional limitation that may encumber the interpretation of luminescence ages. [ABSTRACT FROM AUTHOR]

Lakes and reservoirs act as sinks for both catchment and atmospherically derived particulates and so their sediments can provide valuable information on temporal changes in these inputs. While the use of lake sediments as environmental archives is well established, reservoir sediments have less frequently been used as temporal records. Yet, for investigating pollution histories, reservoirs are ostensibly of greater interest: they are generally located close to urban and industrial sources of pollution and accumulate sediment rapidly and over similar time periods to major emissions of pollutants. The lack of interest in reservoir sediments stems from the perception that fluctuating water levels are likely to result in significant sediment disturbance. This perception is sustained, perhaps mistakenly, by a lack of research into reservoir sedimentary systems. There is, therefore, a need to review the available published research on reservoir sedimentation processes and patterns, the relatively few studies that have used reservoir sediments and relevant studies from the lake-sediment literature, and thus critically evaluate the potential and problems of using reservoir sediments as temporal records of pollution. Current understanding of the processes of sedimentation and resulting distributions are reviewed. Some significant differences between sedimentation in lakes and reservoirs are highlighted and the implications for sampling and interpretation of sedimentary records discussed. It is suggested that, at present, a valuable resource is being underutilized and it is demonstrated that, where sediment deposition patterns are taken into account, reservoir sedimentary records can provide important data for reconstructing past atmospheric and catchment pollutant inputs. [ABSTRACT FROM AUTHOR]

Modelling ice and snow melt is of large practical and scientific interest, including issues such as water resource management, avalanche forecasting, glacier dynamics, hydrology and hydrochemistry, as well as the response of glaciers to climate change. During the last few decades, a large variety of melt models have been developed, ranging from simple temperature-index to sophisticated energy-balance models. There is a recent trend towards modelling with both high temporal and spatial resolution, the latter accomplished by fully distributed models. This review discusses the relevant processes at the surface-atmosphere interface, and their representation in melt models. Despite considerable advances in distributed melt modelling there is still a need to refine and develop models with high spatial and temporal resolution based on moderate input data requirements. While modelling of incoming radiation in mountain terrain is relatively accurate, modelling of turbulent fluxes and spatial and temporal variability in albedo constitute major uncertainties in current energy-balance melt models, and thus need further research. [ABSTRACT FROM AUTHOR]

Flood frequency analysis (FFA) is a form of risk analysis, yet a risk analysis of the activity of FFA itself is rarely undertaken. The recent literature of FFA has been characterized by: (1) a proliferation of mathematical models, lacking theoretical hydrologic justification, but used to extrapolate the return periods of floods beyond the gauged record; (2) official mandating of particular models, which has resulted in (3) research focused on increasingly reductionist and statistically sophisticated procedures for parameter fitting to these models from the limited gauged data. These trends have evolved to such a refined state that FFA may be approaching the 'limits of splitting'; at the very least, the emphasis was shifted early in the history of FFA from predicting and explaining extreme flood events to the more soluble issue of fitting distributions to the bulk of the data. However, recent evidence indicates that the very modelling basis itself may be ripe for revision. Self-similar (power law) models are not only analytically simpler than conventional models, but they also offer a plausible theoretical basis in complexity theory. Of most significance, however, is the empirical evidence for self-similarity in flood behaviour. Self-similarity is difficult to detect in gauged records of limited length; however, one positive aspect of the application of statistics to FFA has been the refinement of techniques for the incorporation of historical and palaeoflood data. It is these data types, even over modest timescales such as 100 years, which offer the best promise for testing alternative models of extreme flood behaviour across a wider range of basins. At stake is the accurate estimation of flood magnitude, used widely for design purposes: the power law model produces far more conservative estimates of return period of large floods compared to conventional models, and deserves closer study. [ABSTRACT FROM AUTHOR]

This review seeks to examine connections between hydrology and biogeochemistry at the landscape scale. A review of research on landscape structure and organization provides a context for what follows, and seeks to integrate work at relevant scales in ecology and geomorphology; the degree of functional 'connectedness' between different landscape elements provides the key theme. Following a review of hillslope hydrology, links between hillslope runoff pathways and nutrient dynamics are then considered. We focus in particular on riparian zones, where nutrient dynamics has relevance for water-quality management in catchments. In conclusion, we argue that future studies need to focus on the critical near-stream zone, given its importance in coupling hillslope and channel systems. [ABSTRACT FROM AUTHOR]

Miniature varieties of cryogenic mounds that are capable of forming in seasonally frozen ground are commonly referred to as earth hummocks (e.g., North America), thúfur (e.g., Greenland and Iceland) and pounus (Fennoscandia). Over the past few decades there has been a consistent interest to study earth hummocks from a variety of environmental settings. This review summarizes the current knowledge of earth hummocks, highlighting aspects on the external and internal morphology, and thermal characteristics, which may assist to explain hummock formation. Several hypotheses have been proposed for the genesis of earth hummocks, including the 'cryoexpulsion' of clasts, hydrostatic and cryostatic pressure, cellular circulation, and differential frost heave. These hypotheses are critically evaluated and some research gaps identified. It emerges that considerable advances have been made towards an improved understanding of earth hummock development, modification and disintegration. Much progress has been made in the application of earth hummock studies to a variety of environmental research approaches such as palaeoenvironmental reconstructions and assessing their impact on hillslope drainage. [ABSTRACT FROM AUTHOR]

The article informs that several journals published special issues in 2003 in which all, or the majority, of papers focused on arid zone geomorphology. Most of these special issues arise from recent conferences and they cover a variety of themes including wind erosion, linkages between fluvial, lacustrine and aeolian systems in drylands and late Quaternary environmental change in African drylands. A special issue of the journal "Quaternary Science Reviews" focused on loess and the Dust Indicators and Records of Terrestrial and Marine Palaeoenvironmental database, whilst papers from the First International Workshop on Sandstorms and Associated Dustfall were published in the journal "Water, Air and Soil Pollution."

Dambos are shallow, seasonally waterlogged, tropical and subtropical African wetlands. Their importance, through their role in agriculture and water supply to downstream river networks, has been widely acknowledged. As a result, much research has been conducted on the hydrological functions of dambos and their hydrogeological structures, in an attempt to better understand, utilize and manage this regionally ubiquitous landform. However, these studies have resulted in little consensus regarding the geomorphology of dambos, their hydrological regimes and the hydrogeological model that drives those regimes. This review paper, focusing on dambo hydrology, hydrogeology and their primary determinants, highlights the key issues of the debate and draws some overriding conclusions from the divergent literature. Five hypotheses are proposed based on these conclusions, in an attempt to focus future dambo research efforts. [ABSTRACT FROM AUTHOR]

Presents a progress report from the published works relating to coastal geomorphology from last year in Australia. Productiveness of its goal to provide a useful and quick reference for academics, scientist and students; Identification of Quaternary evolution of the lower Saxony coast over a number of transgression based on sedimentary evidence; Identification of tsunami as a significant agent of coastal evolution.

Focuses on the effects of weather and climate impact on human activities in the U.S. Usage of climate data and information on broad range of social, economic and environmental applications; Implications of heat waves on lifestyles and health of affected population.

Comments on the issues regarding the notion on physical geography by Charles Darwin. Arguments over the elements of Darwin's theory about expedition and geography; Assertion on the emphasis of an analogy with the organism in preference to ecology; Interpretation of the evolution theory of Darwin in the sense of change through time or social struggle and selection.

Examines the scope of research into fluvial geomorphology for the two-year period between July 2001 and July 2003. Importance of palaeofluvial investigations on the evolution of fluvial systems and the imprint of the past on present-day forms; Function of sediment delivery in the transfer of residues from hillslopes to bodies of waters; Significance of predicting channel pattern and morphology in climate changes.

The article focuses on Coastal geomorphology in the twenty-first century. Coastal geomorphology has, over the last decade, experienced a particularly unique stage of evolution, where established theory has been both confirmed and challenged, if not overtaken, by rapid advances in field logistics and instrumentation, computing capabilities and applications and by an increased globalization of the science itself. Despite all the recent advances, significant and often persistent questions remain in the knowledge of coastal systems.

Reports on the views of Ronald Peel on the nature of desert geomorphology in Great Britain. Explanation about the questions of the climatic history of the present arid zone; Evidences for more humid conditions; Difficulty in quantifying the degree of climate change.

Editorial. Provides an overview of advances in periglacial research. History of systematic studies of periglacial geomorphology; Periglacial research topics addressed in the December 2002 issue of the journal 'Progress in Physical Geography'; Increased interest of other earth scientists in periglacial research; Processes that have been assigned special roles in periglacial environments.