scholarly journals The Circulation Response to Resolved Versus Parametrized Orographic Drag Over Complex Mountain Terrains

2018 ◽  
Vol 10 (10) ◽  
pp. 2527-2547 ◽  
Author(s):  
Annelize Niekerk ◽  
Irina Sandu ◽  
Simon B. Vosper
Keyword(s):  
Mountain Terrains ◽  
Orographic Drag

Downhill Running to Enhance Operational Performance in Mountain Terrains: Report No. 94-36

1994 ◽  
Author(s):  
P. G. Law ◽  
H. W. Goforth ◽  
W. K. Prusaczyk ◽  
T. Sopchick-Smith ◽  
A. C. Vailas
Keyword(s):  
Operational Performance ◽  
Downhill Running ◽  
Mountain Terrains

scholarly journals An Overture for eCAM: Science, Technology and Innovation Initiation for Prosperous, Healthy Nepal

2011 ◽  
Vol 2011 ◽  
pp. 1-4
Author(s):  
Krishna Kaphle ◽  
Dinesh Raj Bhuju ◽  
Pramod Kr Jha ◽  
Hom Nath Bhattarai
Keyword(s):  
Medicinal Plants ◽  
Natural Resources ◽  
Royal Academy ◽  
Science And Technology ◽  
Modern Times ◽  
Technology And Innovation ◽  
Science Technology ◽  
Per Capita ◽  
Mountain Terrains ◽  
Science Technology And Innovation

Nepal the “Shangri-La” in the lap of the Himalayas is gearing up for modern times as it starts rebuilding after a decade of senseless violence and destruction. The nation one of the poorest in the global development index is rich in natural resources and biodiversity. Reports of medicinal plants far exceeding those recorded and reported so far are encouraging and at the same time concerns for medicinal plants under threat as a result of overexploitation are emerging from Nepal. The harsh mountain terrains, lack of industrialization and harnessing potentiality of its areas of strength; water; natural resources and tourism make it poor in per capita income which averages ~ 300 US$, with half the population living under >1$ a day. Nepal is beginning to realize that the way ahead is only possible through the path of Science and Technology (ST). Nepal Academy of Science and Technology formerly known as Royal Academy of Science and Technology organized the fifth national conference held every 4 years that took place in the capital Kathmandu during November 10-12, 2008. The ST initiation event saw the participation of ~ 1400 people representing over 150 organizations from the country and experts from abroad. The theme for the fifth national meet was “Science, Technology and Innovation for Prosperous Nepal”. Complementary and Alternative Medicine (CAM) was an important theme in the event as the realization for the need of ST research focused in CAM for harnessing the chemo diversity potential was univocally approved.

Analysis of Brake Failure and Runaway Accidents in Mountain Terrain in Canada

2013 ◽  
Author(s):  
Daoxing Chen
Keyword(s):  
Dynamics Simulation ◽  
Contributing Factors ◽  
Friction Heat ◽  
Mountain Terrain ◽  
Maintenance Practice ◽  
Train Operation ◽  
Brake Application ◽  
Property Loss ◽  
Train Dynamics ◽  
Mountain Terrains

A number of serious rail runaway accidents have occurred in recent years on long and high grade downhill tracks in mountain terrains in Canada, causing fatal injuries and huge property loss. They were caused by brake failure, misunderstanding of brake features, maintenance deficiency and/or improper brake application on the trains. Train dynamics simulation, brake ratio testing, and dynamometer testing on friction heat fade helped disclose the causes and contributing factors in the cases presented in this paper. Guidelines were revised for safer train operation, equipment requirements and maintenance practice in the mountain terrain conditions.

Evaluation of WRF Simulations With Different Selections of Subgrid Orographic Drag Over the Tibetan Plateau

2017 ◽  
Vol 122 (18) ◽  
pp. 9759-9772 ◽  
Author(s):  
X. Zhou ◽  
A. Beljaars ◽  
Y. Wang ◽  
B. Huang ◽  
C. Lin ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
The Tibetan Plateau ◽  
Orographic Drag

scholarly journals Soil Erosion on Mountain Trails in Eastern Iberian Peninsula

Proceedings ◽  
2020 ◽  
Vol 30 (1) ◽  
pp. 80
Author(s):  
Artemi Cerdà ◽  
David Salesa ◽  
Jesús Rodrigo-Comino ◽  
Gaspar Mora-Navarro ◽  
Enric Terol ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Slope Angle ◽  
Parent Material ◽  
Rock Outcrops ◽  
Erosion Rates ◽  
Soil Erosion Rates ◽  
Mountain Terrains ◽  
Study Sites ◽  
Coastal Land ◽  
Clear Relation

A review on trial erosion shows that soil erosion rates are one to three orders of magnitude higher than the ones recommended as sustainable. This is threatening the sustainable managements of mountain terrains, mainly in the popular hiking paths. The warm temperatures characterize Eastern Spain in winter, which results in visitors from northern Europe to walk in the coastal land mountainous terrain. This increases the pressure to the currently highly visited most popular paths. We selected representative transects of the trails of Serra de Bérnia, Puigcampana, Penyagolosa, Montcabré, Serra del Sit, Aitana, Les Tres Creus, Caroig, Cupurutxo and Circ de la Safor. All the selected study sites have Limestone parent material, and a scrubland as vegetation cover and the selected slope angle ranged in average between 5 and 10%. The surveys showed that soil erosion rates measured with a topographical method range from 13 till 450 Mg ha−1 y−1. There is a clear relation between the number of users and the damage done on the trails; and we found that short cuts are the areas that contribute with fresh sediment. Rock outcrops are found in 34% of the measured trail sections and this is a good example how the complete soil can be lost as a consequence of recreational activities.

scholarly journals COnstraining ORographic Drag Effects (COORDE): A Model Comparison of Resolved and Parametrized Orographic Drag

2020 ◽  
Vol 12 (11) ◽  
Author(s):  
Annelize Niekerk ◽  
Irina Sandu ◽  
Ayrton Zadra ◽  
Eric Bazile ◽  
Takafumi Kanehama ◽  
...  
Keyword(s):  
Model Comparison ◽  
Orographic Drag

COnstraining ORographic Drag Effects (COORDE): A model intercomparison of resolved and parametrized orographic drag

2020 ◽  
Author(s):  
Annelize VanNiekerk ◽  
Irina Sandu
Keyword(s):  
Gravity Wave ◽  
Complex Terrain ◽  
Spatial Scales ◽  
Wave Drag ◽  
Large Spread ◽  
Numerical Experimentation ◽  
Wave Effects ◽  
Atmospheric Gravity ◽  
The Impact ◽  
Orographic Drag

<p>Mountains are know to impact the atmospheric circulation on a variety of spatial scales and through a number of different processes. They exert a drag force on the atmosphere both locally through deflection of the flow and remotely through the generation of atmospheric gravity waves. The degree to which orographic drag parametrizations are able to capture the complex impacts on the circulation from realistic orography in high resolution simulations is examined here. We present results from COnstraing ORographic Drag Effects (COORDE), a project joint with the Working Group on Numerical Experimentation (WGNE) and Global Atmospheric System Studies (GASS). The aim of COORDE is to validate parametrized orographic drag in several operational models in order to determine both systematic and model dependent errors over complex terrain. To do this, we compare the effects of parametrized orographic drag on the circulation with those of the resolved orographic drag, deduced from km-scale resolution simulations which are able to resolve orographic low-level blocking and gravity-wave effects. We show that there is a large spread in the impact from parametrized orographic drag between the models but that the impact from resolved orography is much more robust. This is encouraging as it means that the km-scale simulations can be used to evaluate the caveats of the existing orographic drag parametrizations. Analysis of the parametrized drag tendencies and stresses shows that much of the spread in the parametrized orographic drag comes from differences in the partitioning of the drag into turbulent and flow blocking drag near the surface. What is more, much of the model error over complex terrain can be attributed to deficiencies in the parametrized orographic drag, particularly coming from the orographic gravity wave drag.</p>

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