Diurnal freeze–thaw depth in rockwalls: Field measurements and theoretical considerations

1994 ◽  
Vol 19 (5) ◽  
pp. 423-435 ◽  
Author(s):  
Norikazu Matsuoka
Author(s):  
Takeru KANAZAWA ◽  
Takuro NAKAMURA ◽  
Junichi SAKAGUCHI ◽  
Kazuhiro KAWAGUCHI

2021 ◽  
Vol 35 (3) ◽  
pp. 590-622
Author(s):  
Gianni Pascoli

The Hessdalen lights (HLs in the following) are luminous, floating,  more or less spherical atmospheric phenomena,  with a lifetime  of a few  seconds to sometimes several minutes. These phenomena are seen in the Hessdalen Valley in Norway for decades.  Unfortunately  a full understanding of these baffling events is still lacking in spite of solid  working  scientific   projects  intended  to explain them. This  paper  tries  to  improve  the  situation.  It raises the questions where the energy for the creation of the HLs  comes from, and what was  its nature : (geo) chemical, electric or still other ?   We propose a new  scenario for the Hessdalen lights. It exploits the recent idea of stable and traversable wormholes  whose the potential existence  is beginning to be  recognized in physics. Even though appearing highly  speculative, this hypothesis  has not been so far explored  elsewhere  while it could supply  a full  description  of the wholeness of the  phenomenon. On the other side  even if  the probability that a HL could indeed be a wormhole is may be low,  this question should not dismissed out of hand. These  theoretical considerations could  help to increase   knowledge and understanding  of  both  the HLs  and the wormholes, drawing mutual enrichment. In other words HLs  could betray the presence of hidden wormholes and we must not let slip through our fingers  this possibility even if it is very tiny.  In this framework we discuss of the stability, the energetics and the oversized dimension of the HLs. In physics the  final arbiter  is not the theory but the experiment. Thus some “simple” experiments are eventually  suggested  (high time resolution photometry and magnetic field measurements).  Eventually, if the process described is real and after mastering it,  there is a free and inexhaustible source of energy   that would be derived,  a tremendous breakthrough after which we could forget the controlled nuclear fusion. Regarding its structure, the paper is divided in four paragraphs 1, 2,3, 4 independent of each other.  Illustrative pictures help  to understand the text.  


1971 ◽  
Vol 51 (2) ◽  
pp. 249-259 ◽  
Author(s):  
R. L. HARLAN ◽  
J. A. BANNER ◽  
R. ALLAN FREEZE

The value of electrical-resistance measurements from soil moisture blocks in a freeze-thaw environment can be enhanced by laboratory calibration in the subzero temperature range to provide a measure of unfrozen water contents. Laboratory studies show that, in the temperature range of incipient freezing and thawing (−3 to 0 C) electrical resistance as measured with Colman fiberglas resistance blocks is independent of temperature. At temperatures less than −3 C, electrical resistance is dependent upon both the nature of the porous medium and temperature, but is independent of the total water content of the soil-water system. Results from the laboratory investigations are extended to the interpretation of field measurements of electrical resistance for a soil profile at Calgary, Alberta, Canada.


2006 ◽  
Vol 52 (179) ◽  
pp. 631-643 ◽  
Author(s):  
Perry Bartelt ◽  
Othmar Buser ◽  
Katharina Platzer

AbstractA fundamental problem in avalanche science is understanding the interaction between frictional processes taking place at the basal running surface and dissipative mechanisms within the avalanche body. In this paper, we address this question by studying how kinetic energy is dissipated into heat in snow avalanches. In doing so we consider the effect of random granular fluctuations and collisions in depth-averaged snow avalanche models. We show that relationships between the size of the granular fluctuations and the energy dissipated by granular collisions can be obtained by studying the energy input required to maintain steady-state flows. The energy input for granular fluctuations comes from mechanisms operating in the basal layer. The kinetic energy of the flow at the basal layer is converted to granular agitation energy, a random kinetic energy, which in turn is dissipated as heat by both viscous shearing and inelastic collisions at higher levels in the avalanche profile. Thus granular fluctuations play a crucial role in understanding the total dissipation process. We apply our theoretical considerations to develop a constitutive model for dense snow avalanches and are able to accurately model steady-state velocity profiles of both snow-chute experiments and field measurements.


Sign in / Sign up

Export Citation Format

Share Document