4 resultados para RESONANCE SPECTRA
em Aquatic Commons
Resumo:
Studies by the Freshwater Biological Association over the last 25 years have supplied data relevant to the levels of acidity in local soils and water before the onset of industrial pollution and current interest in acid rain. This article reviews published analysis from cores of lake sediments, in or near the catchment of the River Duddon. Electron spin resonance spectra of humic acids and iodine values confirm evidence from pollen analysis for a history of progressive acidification of the source material of lake sediments since before 5000 radiocarbon years, in upland catchments of the Lake District. Processes involved included: removal of basic ions from soils by rainfall, the effects of which were intensified by removal by man of deciduous forest; acidification of soils and waters by decomposition products of Calluna and further acidification of waters by Sphagnum species which colonized habitats where drainage became impeded by paludification processes.
Resumo:
Marine sportfishing in southern California is a huge industry with annual revenues totaling many billions of dollars. However, the stocks of lingcod and six rockfish species have been declared overfished by the Pacific Fisheries Management Council. As part of a multifaceted fisheries management plan, marine conservation areas, covering many million square nautical miles, have been mandated. To monitor the recovery of the rockfish stocks in these areas, scientists are faced with the following challenges: 1) multiple species of rockfish exist in these areas; 2) the species reside near or on the bottom at depths of 80 to 300 m; and 3) they are low in numerical density. To meet these challenges, multifrequency echosounders, multibeam sonar, and cameras mounted on remotely operated vehicles are frequently used (Reynolds et al., 2001). The accuracy and precision of these echosounder results are largely dependent upon the accuracy of the species classification and target strength estimation (MacLennan and Simmonds, 1992).
Resumo:
I tentatively conclude ... that the QBO may be either modulated or amplified by atmospheric tidal resonances. The generally strong correlation between the QBO and tropical Southern Oscillation, in turn, suggests that one or probably both of these stratospheric and tropospheric oscillations are modulated or amplified by the same tidal-resonance system. ... The strikingly weaker correlation between the Southern Oscillation and El Niño events strongly suggests that some critical parameters are missing in the GCMs specifically designed to predict El Niño occurrence.
Resumo:
Recent papers provide detailed analyses of more than 40 high-resolution time series culled from the extensive paleoclimate literature that appear to define cyclical elements of the Solar-Insolation/Tidal-Resonance Climate Model. This model was earlier referred to as the Milankovitch/Pettersson Climatic Theory. This paper provides comparable analyses of an additional 20 or so, evidently supportive, climate and volcanic time series. The tree-ring, historical, pollen, cultural, time-frequency, and hydrologic records range in length from 400 to 90,000 years and spatially from Alaska to Tierra del Fuego.