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461.
The physical significance of a negative correlation between a varve record from Mud Lake, British Columbia, and temperature
is discussed in the context of a process-network. The process-network is defined as the system of temporally and spatially
connected processes involved in the transfer of a signal from climate to varved glaciolacustrine sediment. The six systems
defining the network include climate, glacier, fluvial, geomorphic, terrestrial biologic and lacustrine systems to which each
process belongs. A literature review outlines significant variation in the strength and character of correlations between
components of the process-network and highlights that more comprehensive interpretations of varves as a hydroclimatic proxy
require an improved understanding of the process-network. Documenting each process in the network is integral to informing
a more complete model of this system, identifying processes that constitute signal transfer and assessing hydroclimatic proxies
based on linear correlation. Such documentation is of growing importance as varved lacustrine sediments are increasingly used
as a hydroclimatic proxy. The complex nature of the process-network requires greater emphasis on interdisciplinary cooperation
and alternative methods to the linear statistical model. 相似文献
462.
The angular variation of elastic and inelastic scattering cross-sections has been calculated and used to study the energy deposition by precipitating electrons with the help of Monte Carlo Method. Monoenergetic, power law electron spectrum with isotropic and monodinational incidence starting at an altitude of 300 km have been used to obtain the angular and energy distributions at certain height intervals. In these calculations constant magnetic field has been used. 相似文献
463.
Lithology and Mineral Resources - 相似文献
464.
Rocket-borne observations of the extinction of solar hydrogen Lyman-alpha radiation made during the solar eclipses of 20 May 1966 at Karistos for normal and 44% visibility and of 7 March 1970 at East Quoddy for normal, 10% and 0.6% visibility have been used to study the variation of temperature in the mesosphere during these events. It is seen that near the mesopause the decrease of temperature at Karistos is by 20° K for 44% visibility and at East Quoddy by 100° K for 0.6% visibility. Possible causes of these temperature variationsvis-a-vis molecular oxygen and pressure variations have been briefly discussed. 相似文献
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468.
Hilkka Pellikka Jenni Rauhala Kimmo K. Kahma Tapani Stipa Hanna Boman Antti Kangas 《Natural Hazards》2014,74(1):197-215
We present four case studies of exceptional wave events of meteorological origin, observed on the Finnish coast in the summers of 2010 and 2011. Eyewitnesses report unusually rapid and strong sea-level variations (up to 1 m in 5–15 min) and strong oscillating currents during these events. High-resolution sea-level measurements confirm the eyewitness observations, but the oscillations recorded by tide gauges mostly have a considerably smaller amplitude. The oscillations coincide with sudden jumps in surface air pressure at coastal observation stations, related to the passage of squall lines or gust fronts. These fronts propagate above the sea at a resonant speed, allowing efficient energy transfer between the atmospheric disturbance and the sea wave that it generates. Thus, we interpret the observed sea-level oscillations as small meteotsunamis, long tsunami-like waves generated by meteorological processes and resonance effects. 相似文献
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470.
Optical and SEM observations of phosphorites reveal that mineralization is concentrated on ooids and micro-oncoids. The coated grains occur within microbial mats. Microbial mats represent the formational environment of the ooids and oncoids. Both coated grains and mats exhibit similar filamentous micro-organisms. The mat filaments show no fixed orientation and they merge with the concentrically oriented filaments of the coated grains. The branching nature and chlamydospore-like structures of filaments suggest that both mat and coated grains have been formed by fungi. Some coated grains appear to have been slightly disturbed and sometimes mobilized from their sites of formation due to separation from the parent mat resulting perhaps from contraction/fragmentation. The voids so created within the mat had been later filled with either micrite or sparite. 相似文献