Modeling the planform evolution of confined meandering rivers

2020 ◽  
Author(s):  
Hossein Amini ◽  
Federico Monegaglia ◽  
Simone Zen ◽  
Stefano Lanzoni ◽  
Guido Zolezzi ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Case Studies ◽  
Significant Influence ◽  
Dynamics Model ◽  
Meandering Rivers ◽  
Periodic Sequences ◽  
Morphodynamic Modeling ◽  
Strong Confinement ◽  
Meander Model ◽  
Good Agreement

<p>The presence of lateral planimetric constraints preventing free migration and avulsion has a significant influence on the planform dynamics of river meanders. This particular confined kind of meandering rivers is definitely understudied, especially in comparison to freely migrating ones. Through a semi-analytical meander model, here we attempt to investigate the effect of the confined floodplain width through a morphodynamic modeling approach. The confined floodplain width is defined as the width between symmetric lateral confinement where the river is free to migrate, on the planform pattern and dynamics. Model results illustrate that weak confinement (i.e. loose floodplain boundaries) increases planform irregularity, with the river centerline preferentially lying close to floodplain boundaries, while strong confinement (tight floodplain boundaries) leads to a remarkable planform regularity, constituted by periodic sequences of sawtooth-shaped meanders. Bend orientation is reminiscent of the sub/super-resonant regime regardless of the confinement width. Model results are supported by good agreement with available field and remote sensing observation on selected case studies of confined meandering rivers in Canada previously studied by Nicoll and Hickin (2014).</p><p> </p>

scholarly journals Best Practices In Multilanguage Satellite Remote Sensing Training: Case Studies In Spanish-Speaking Countries [Education]

2021 ◽  
Vol 9 (2) ◽  
pp. 105-111
Author(s):  
Ana Prados ◽  
Erika Podest ◽  
David G Barbato ◽  
Annelise Carleton-Hug ◽  
Brock Blevins ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Best Practices ◽  
Case Studies ◽  
Satellite Remote Sensing ◽  
Spanish Speaking ◽  
Training Case

scholarly journals Extraterrestrial Influences on Remote Sensing in the Earth’s Atmosphere

2021 ◽  
Vol 13 (5) ◽  
pp. 890
Author(s):  
Aleksandra Nina ◽  
Milan Radovanović ◽  
Luka Č. Popović
Keyword(s):  
Remote Sensing ◽  
Solar System ◽  
Solar Radiation ◽  
Significant Influence ◽  
Coming Out ◽  
Outer Space ◽  
Signal Propagation ◽  
Atmospheric Parameters ◽  
Atmospheric Disturbances ◽  
Propagation Paths

Atmospheric properties have a significant influence on electromagnetic (EM) waves, including the propagation of EM signals used for remote sensing. For this reason, changes in the received amplitudes and phases of these signals can be used for the detection of the atmospheric disturbances and, consequently, for their investigation. Some of the most important sources of the temporal and space variations in the atmospheric parameters come from the outer space. Although the solar radiation dominates in these processes, radiation coming out of the solar system also can induces enough intensive disturbance in the atmosphere to provide deflections in the EM signal propagation paths. The aim of this issue is to present the latest research linking events and processes in outer space with changes in the propagation of the satellite and ground-based signals used in remote sensing.

scholarly journals Imaging Spectroscopy for Conservation Applications

2021 ◽  
Vol 13 (2) ◽  
pp. 292
Author(s):  
Megan Seeley ◽  
Gregory P. Asner
Keyword(s):  
Remote Sensing ◽  
Decision Making ◽  
Case Studies ◽  
Spatial Scales ◽  
Imaging Spectroscopy ◽  
Remote Sensing Data ◽  
Decision Makers ◽  
High Spectral Resolution ◽  
Conservation Areas ◽  
Broad Array

As humans continue to alter Earth systems, conservationists look to remote sensing to monitor, inventory, and understand ecosystems and ecosystem processes at large spatial scales. Multispectral remote sensing data are commonly integrated into conservation decision-making frameworks, yet imaging spectroscopy, or hyperspectral remote sensing, is underutilized in conservation. The high spectral resolution of imaging spectrometers captures the chemistry of Earth surfaces, whereas multispectral satellites indirectly represent such surfaces through band ratios. Here, we present case studies wherein imaging spectroscopy was used to inform and improve conservation decision-making and discuss potential future applications. These case studies include a broad array of conservation areas, including forest, dryland, and marine ecosystems, as well as urban applications and methane monitoring. Imaging spectroscopy technology is rapidly developing, especially with regard to satellite-based spectrometers. Improving on and expanding existing applications of imaging spectroscopy to conservation, developing imaging spectroscopy data products for use by other researchers and decision-makers, and pioneering novel uses of imaging spectroscopy will greatly expand the toolset for conservation decision-makers.

scholarly journals Remote Sensing Applications for Landslide Monitoring and Investigation in Western Canada

2021 ◽  
Vol 13 (3) ◽  
pp. 366
Author(s):  
Renato Macciotta ◽  
Michael T. Hendry
Keyword(s):  
Remote Sensing ◽  
Case Studies ◽  
Slope Failure ◽  
Landslide Monitoring ◽  
Western Canada ◽  
Extensive Literature ◽  
Sensing Applications ◽  
Remote Sensing Techniques ◽  
Definition Of ◽  
River Valleys

Transportation infrastructure in mountainous terrain and through river valleys is exposed to a variety of landslide phenomena. This is particularly the case for highway and railway corridors in Western Canada that connect towns and industries through prairie valleys and the Canadian cordillera. The fluidity of these corridors is important for the economy of the country and the safety of workers, and users of this infrastructure is paramount. Stabilization of all active slopes is financially challenging given the extensive area where landslides are a possibility, and monitoring and minimization of slope failure consequences becomes an attractive risk management strategy. In this regard, remote sensing techniques provide a means for enhancing the monitoring toolbox of the geotechnical engineer. This includes an improved identification of active landslides in large areas, robust complement to in-place instrumentation for enhanced landslide investigation, and an improved definition of landslide extents and deformation mechanisms. This paper builds upon the extensive literature on the application of remote sensing techniques and discusses practical insights gained from a suite of case studies from the authors’ experience in Western Canada. The review of the case studies presents a variety of landslide mechanisms and remote sensing technologies. The aim of the paper is to transfer some of the insights gained through these case studies to the reader.

Identification of Urban Expansion onto Agricultural Lands Using Satellite Remote Sensing: Two Case Studies in Egypt

1999 ◽  
Vol 14 (1) ◽  
pp. 45-48 ◽  
Author(s):  
M. M. Fahim ◽  
KI. Khalil ◽  
F. Hawela ◽  
H. K. Zaki ◽  
M. N. El-Mowelhi ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Case Studies ◽  
Satellite Remote Sensing ◽  
Urban Expansion ◽  
Agricultural Lands

scholarly journals Validation of aerosol backscatter profiles from Raman lidar and ceilometer using balloon-borne measurements

2021 ◽  
Vol 21 (3) ◽  
pp. 2267-2285
Author(s):  
Simone Brunamonti ◽  
Giovanni Martucci ◽  
Gonzague Romanens ◽  
Yann Poltera ◽  
Frank G. Wienhold ◽  
...  
Keyword(s):  
Remote Sensing ◽  
In Situ Measurements ◽  
Aerosol Size Distribution ◽  
Spatial And Temporal Variability ◽  
Raman Lidar ◽  
Backscatter Coefficient ◽  
Custom Made ◽  
Aerosol Backscatter ◽  
Good Agreement

Abstract. Remote-sensing measurements by light detection and ranging (lidar) instruments are fundamental for the monitoring of altitude-resolved aerosol optical properties. Here we validate vertical profiles of aerosol backscatter coefficient (βaer) measured by two independent lidar systems using co-located balloon-borne measurements performed by Compact Optical Backscatter Aerosol Detector (COBALD) sondes. COBALD provides high-precision in situ measurements of βaer at two wavelengths (455 and 940 nm). The two analyzed lidar systems are the research Raman Lidar for Meteorological Observations (RALMO) and the commercial CHM15K ceilometer (Lufft, Germany). We consider in total 17 RALMO and 31 CHM15K profiles, co-located with simultaneous COBALD soundings performed throughout the years 2014–2019 at the MeteoSwiss observatory of Payerne (Switzerland). The RALMO (355 nm) and CHM15K (1064 nm) measurements are converted to 455 and 940 nm, respectively, using the Ångström exponent profiles retrieved from COBALD data. To account for the different receiver field-of-view (FOV) angles between the two lidars (0.01–0.02∘) and COBALD (6∘), we derive a custom-made correction using Mie-theory scattering simulations. Our analysis shows that both lidar instruments achieve on average a good agreement with COBALD measurements in the boundary layer and free troposphere, up to 6 km altitude. For medium-high-aerosol-content measurements at altitudes below 3 km, the mean ± standard deviation difference in βaer calculated from all considered soundings is −2 % ± 37 % (−0.018 ± 0.237 Mm−1 sr−1 at 455 nm) for RALMO−COBALD and +5 % ± 43 % (+0.009 ± 0.185 Mm−1 sr−1 at 940 mm) for CHM15K−COBALD. Above 3 km altitude, absolute deviations generally decrease, while relative deviations increase due to the prevalence of air masses with low aerosol content. Uncertainties related to the FOV correction and spatial- and temporal-variability effects (associated with the balloon's drift with altitude and different integration times) contribute to the large standard deviations observed at low altitudes. The lack of information on the aerosol size distribution and the high atmospheric variability prevent an accurate quantification of these effects. Nevertheless, the excellent agreement observed in individual profiles, including fine and complex structures in the βaer vertical distribution, shows that under optimal conditions, the discrepancies with the in situ measurements are typically comparable to the estimated statistical uncertainties in the remote-sensing measurements. Therefore, we conclude that βaer profiles measured by the RALMO and CHM15K lidar systems are in good agreement with in situ measurements by COBALD sondes up to 6 km altitude.

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