Erosional development of small scale drainage networks

Shaping Planetary Surfaces: The Impact of Liquid and Frozen Water on Hillslope Topography

10.5194/egusphere-egu2020-8180 ◽

2020 ◽

Author(s):

Taylor Smith ◽

Bodo Bookhagen

Keyword(s):

Land Surface ◽

Soil Formation ◽

High Elevation ◽

Small Scale ◽

Primary Role ◽

Planetary Scale ◽

Thaw Cycle ◽

Drainage Networks ◽

Freeze Thaw Cycle ◽

The Impact

The availability of liquid water plays a primary role in controlling the development of topography. Hillslope asymmetry (HA), or slope differences between terrain aspects, has been well-documented in small-scale and field-based studies throughout the world. In this study, we apply a consistent HA analysis method across the entire globe and find that poleward facing hillslopes are on average steeper than equator-facing hillslopes, with the exception of high-latitude, high-elevation, and low-temperature regions where equator-facing slopes tend to be steeper.To test the impact of different land cover and climate regimes on HA, we use global and high-resolution elevation, vegetation and land-surface temperature data to examine erosional process differences between poleward- and equator-facing hillslopes. We find that vegetation supports poleward-steepening, and that low temperatures and high freeze-thaw cycle frequencies enhance equator-steepening of hillslopes. We further show that HA is propagated into the size and form of fluvial drainage networks. We posit that insolation plays a key role in controlling soil-water availability and retention, and thus drives asymmetries in vegetation cover, soil formation rates and landscape form at the planetary scale.

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On the sensitivity of geospatial low impact development locations to the centralized sewer network

Water Science & Technology ◽

10.2166/wst.2018.060 ◽

2018 ◽

Vol 77 (7) ◽

pp. 1851-1860 ◽

Cited By ~ 12

Author(s):

Jonatan Zischg ◽

Peter Zeisl ◽

Daniel Winkler ◽

Wolfgang Rauch ◽

Robert Sitzenfrei

Keyword(s):

Green Infrastructure ◽

Network Performance ◽

Low Impact Development ◽

Small Scale ◽

Runoff Reduction ◽

Drainage Networks ◽

Hybrid Solutions ◽

Random Placement ◽

Hydraulic Network ◽

Pollution Removal

Abstract In the future, infrastructure systems will have to become smarter, more sustainable, and more resilient requiring new methods of urban infrastructure design. In the field of urban drainage, green infrastructure is a promising design concept with proven benefits to runoff reduction, stormwater retention, pollution removal, and/or the creation of attractive living spaces. Such ‘near-nature’ concepts are usually distributed over the catchment area in small scale units. In many cases, these above-ground structures interact with the existing underground pipe infrastructure, resulting in hybrid solutions. In this work, we investigate the effect of different placement strategies for low impact development (LID) structures on hydraulic network performance of existing drainage networks. Based on a sensitivity analysis, geo-referenced maps are created which identify the most effective LID positions within the city framework (e.g. to improve network resilience). The methodology is applied to a case study to test the effectiveness of the approach and compare different placement strategies. The results show that with a simple targeted LID placement strategy, the flood performance is improved by an additional 34% as compared to a random placement strategy. The developed map is easy to communicate and can be rapidly applied by decision makers when deciding on stormwater policies.

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Climatic and Biotic Controls on Topographic Asymmetry at the Global Scale

10.5194/egusphere-egu21-9758 ◽

2021 ◽

Author(s):

Taylor Smith ◽

Bodo Bookhagen

Keyword(s):

Vegetation Cover ◽

High Elevation ◽

Global Scale ◽

Small Scale ◽

Primary Role ◽

Analysis Method ◽

Driving Mechanisms ◽

Drainage Networks ◽

Scale Field ◽

Work Supports

Insolation differences play a primary role in controlling microclimate and vegetation cover, which together influence the development of topography. Topographic asymmetry (TA), or slope differences between terrain aspects, has been well documented in small-scale, field-based, and modeling studies. Here we combine a suite of environmental (e.g., vegetation, temperature, solar insolation) and topographic (e.g., elevation, drainage network) data to explore the driving mechanisms and markers of TA on a global scale. Using a novel empirical TA analysis method, we find that (1) steeper terrain has higher TA magnitudes, (2) globally, pole-facing terrain is on average steeper than equator-facing terrain, especially in mid-latitude, tectonically quiescent, and vegetated landscapes, and (3) high-elevation and low-temperature regions tend to have terrain steepened towards the equator. We further show that there are distinct differences in climate and vegetation cover across terrain aspects, and that TA is reflected in the size and form of fluvial drainage networks. Our work supports the argument that insolation asymmetries engender differences in local microclimates and vegetation on opposing terrain aspects, which broadly encourage the development of asymmetric topography across a range of lithologic, tectonic, geomorphic, and climatic settings.

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Reasons to strike first

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000840 ◽

2019 ◽

Vol 42 ◽

Author(s):

William Buckner ◽

Luke Glowacki

Keyword(s):

Intergroup Conflict ◽

Small Scale

Abstract De Dreu and Gross predict that attackers will have more difficulty winning conflicts than defenders. As their analysis is presumed to capture the dynamics of decentralized conflict, we consider how their framework compares with ethnographic evidence from small-scale societies, as well as chimpanzee patterns of intergroup conflict. In these contexts, attackers have significantly more success in conflict than predicted by De Dreu and Gross's model. We discuss the possible reasons for this disparity.

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Exploring Coronal Structures with SOHO

International Astronomical Union Colloquium ◽

10.1017/s0252921100064915 ◽

2000 ◽

Vol 179 ◽

pp. 403-406

Author(s):

M. Karovska ◽

B. Wood ◽

J. Chen ◽

J. Cook ◽

R. Howard

Keyword(s):

Solar Corona ◽

Image Enhancement ◽

Coronal Mass Ejections ◽

Dynamical Evolution ◽

Small Scale ◽

Low Contrast ◽

Contrast Structures ◽

Scale Structures ◽

Small Scale Structures ◽

Coronal Structures

AbstractWe applied advanced image enhancement techniques to explore in detail the characteristics of the small-scale structures and/or the low contrast structures in several Coronal Mass Ejections (CMEs) observed by SOHO. We highlight here the results from our studies of the morphology and dynamical evolution of CME structures in the solar corona using two instruments on board SOHO: LASCO and EIT.

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Scanning tunneling microscopy and atomic force microscopy: New tools for biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155864 ◽

1989 ◽

Vol 47 ◽

pp. 778-779

Author(s):

CE Bracker ◽

P. K. Hansma

Keyword(s):

Physical Property ◽

Scanning Probe ◽

Scanning Tunneling ◽

Small Scale ◽

Tunneling Microscopy ◽

Force Microscopy ◽

New Family ◽

Small Probe ◽

Atomic Force ◽

Transmission Electron

A new family of scanning probe microscopes has emerged that is opening new horizons for investigating the fine structure of matter. The earliest and best known of these instruments is the scanning tunneling microscope (STM). First published in 1982, the STM earned the 1986 Nobel Prize in Physics for two of its inventors, G. Binnig and H. Rohrer. They shared the prize with E. Ruska for his work that had led to the development of the transmission electron microscope half a century earlier. It seems appropriate that the award embodied this particular blend of the old and the new because it demonstrated to the world a long overdue respect for the enormous contributions electron microscopy has made to the understanding of matter, and at the same time it signalled the dawn of a new age in microscopy. What we are seeing is a revolution in microscopy and a redefinition of the concept of a microscope.Several kinds of scanning probe microscopes now exist, and the number is increasing. What they share in common is a small probe that is scanned over the surface of a specimen and measures a physical property on a very small scale, at or near the surface. Scanning probes can measure temperature, magnetic fields, tunneling currents, voltage, force, and ion currents, among others.

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Superstructures and ordering phenomena in ceramic superconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166014 ◽

1996 ◽

Vol 54 ◽

pp. 710-711

Author(s):

R. Gronsky

Keyword(s):

Domain Growth ◽

Small Displacement ◽

Small Scale ◽

Ceramic Superconductors ◽

Oxygen Sublattices ◽

Tweed Contrast ◽

Diffraction Patterns ◽

Representative Image ◽

Static Lattice ◽

Modulation Wavelength

It is now well established that the phase transformation behavior of YBa2Cu3O6+δ is significantly influenced by matrix strain effects, as evidenced by the formation of accommodation twins, the occurrence of diffuse scattering in diffraction patterns, the appearance of tweed contrast in electron micrographs, and the generation of displacive modulation superstructures, all of which have been successfully modeled via simple Monte Carlo simulations. The model is based upon a static lattice formulation with two types of excitations, one of which is a change in oxygen occupancy, and the other a small displacement of both the copper and oxygen sublattices. Results of these simulations show that a displacive superstructure forms very rapidly in a morphology of finely textured domains, followed by domain growth and a more sharply defined modulation wavelength, ultimately evolving into a strong <110> tweed with 5 nm to 7 nm period. What is new about these findings is the revelation that both the small-scale deformation superstructures and coarser tweed morphologies can result from displacive modulations in ordered YBa2Cu3O6+δ and need not be restricted to domain coarsening of the disordered phase. Figures 1 and 2 show a representative image and diffraction pattern for fully-ordered (δ = 1) YBa2Cu3O6+δ associated with a long-period <110> modulation.

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Indirect Assessment of Attitudes with Response-Time-Based Measures

Zeitschrift für Sozialpsychologie ◽

10.1024/0044-3514.37.3.131 ◽

2006 ◽

Vol 37 (3) ◽

pp. 131-139 ◽

Cited By ~ 15

Author(s):

Juliane Degner ◽

Dirk Wentura ◽

Klaus Rothermund

Keyword(s):

Social Cognitive ◽

Incremental Validity ◽

Self Report ◽

Small Scale ◽

Implicit Measures ◽

Scale Theory ◽

Starting Point ◽

Self Reports ◽

Predicting Behavior ◽

Social Cognitive Theories

Abstract: We review research on response-latency based (“implicit”) measures of attitudes by examining what hopes and intentions researchers have associated with their usage. We identified the hopes of (1) gaining better measures of interindividual differences in attitudes as compared to self-report measures (quality hope); (2) better predicting behavior, or predicting other behaviors, as compared to self-reports (incremental validity hope); (3) linking social-cognitive theories more adequately to empirical research (theory-link hope). We argue that the third hope should be the starting point for using these measures. Any attempt to improve these measures should include the search for a small-scale theory that adequately explains the basic effects found with such a measure. To date, small-scale theories for different measures are not equally well developed.

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