Climate and Time in Their Geological Relations: A Theory of Secular Changes of the Earth's ClimateD. Appleton, 1875 - 577 páginas |
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amount of heat antarctic aphelion arctic regions Atlantic beds bottom boulder clay Caithness Carboniferous cause coal consequently considerable density denudation deposits depth descend difference of specific difference of temperature earth's orbit eccentricity ecliptic effect Eocene equal equator equatorial column equatorial regions evidence extent fact feet flow foot foot-pounds force Geol geological geologists glacial epoch glacier globe Grangemouth greater Greenland Gulf-stream heat received ice-cap icebergs inter-tropical James Geikie John Herschel land land-ice latitude lower mass mean temperature melting miles Miocene molecules motion North North Sea northern obliquity ocean-currents oceanic circulation perihelion polar column polar regions poles present probably produce Professor quantity of heat radiation regarding result river rocks sand Scotland sea-level shear slope snow and ice southern hemisphere specific gravity stratified stream striated submergence summer sun's supposed surface theory thickness tion tropical warm periods warm water winds winter
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Página 422 - The climate of the southern part of America appears particularly favourable to the production of peat. In the Falkland Islands almost every kind of plant, even the coarse grass which covers the whole surface of the land, becomes converted into this substance...
Página 101 - It is not necessary to associate with oceanic currents the idea that they must of necessity, as on land, run from a higher to a lower level. So far from this being the case, some currents of the sea actually run up hill, while others run on a level. The Gulf Stream was of the first class.
Página 331 - ... been removed from the general surface in one year ; and there seems no danger of our overrating the mean rate of waste by selecting the Mississippi as our example, for that river drains a country equal to more than half the continent of Europe, extends through twenty degrees of latitude, and therefore through regions enjoying a great variety of climate, and some of its tributaries descend from mountains of great height. The Mississippi is also more likely to afford us a fair test of ordinary...
Página 380 - We had attained an altitude of 5000 feet above the sea-level, and were seventy miles from the coast, in the midst of a vast frozen Sahara immeasurable to the human eye. There was neither hill, mountain, nor gorge, anywhere in view. We had completely sunk the strip of land between the Mer de Glace and the sea, and no object met the eye but our feeble tent, which bent to the storm. Fitful clouds swept over the face of the full-orbed moon, which, descending towards the horizon, glimmered through the...
Página 70 - Now, it is obvious that the shifting of the equatorial current of the Atlantic only a few degrees to the south of its present position — a thing which would certainly take place under the conditions which we have been detailing — would turn the entire current into the Brazilian branch, and instead of flowing chiefly into the Gulf of Mexico, as at present, it would all flow into the Southern Ocean, and the Gulf-stream would consequently be stopped.
Página 379 - The walk to it was richly rewarded by an uncommonly extensive view, which showed us that the inland ice continued constantly to rise towards the interior, so that the horizon towards the east, north, and south was terminated by an ice-border almost as smooth as that of the ocean.
Página 520 - This proves that every molecule resumes its crystalline form the moment after the energy is transferred over to the adjoining molecule. This point being established, every difficulty regarding the descent of the glacier entirely disappears; for a molecule the moment that it assumes the fluid state is completely freed from shearing-force, and can descend by virtue of its own weight without any impediment. All that the molecule requires is simply room or space to advance in.
Página 108 - ... thereby becomes more salt, and, under certain conditions, heavier. When it becomes heavier, it sinks ; and hence we have, due to the salts of the sea, a vertical circulation, namely, a descent of heavier — because salter and cooler — water from the surface, and an ascent of water that is lighter — because it is not so salt — from the depths below
Página 27 - There is actually, therefore, nearly as much heat transferred from the tropical regions by the Gulf-stream as is received from the sun by the entire arctic regions ; the quantity conveyed by the stream to that received from the sun by those regions being as 15 to 18. But we have been assuming in our calculations that the percentage of heat absorbed by the atmosphere is no greater in polar regions than it is at the equator, which is not the case. If we make due allowance for the extra amount absorbed...
Página 104 - India seas; for on one side we have the Caribbean Sea and Gulf of Mexico, with their waters of brine ; "*"• on the other, the great Polar basin, the Baltic, and the North Sea, the two latter with waters that are but little more than brackish.* In one set of these sea-basins the water is heavy ; in the other it is light. Between them the ocean intervenes ; but water is bound to seek and to maintain its level ; and here, therefore, we unmask one of the agents concerned in causing the Gulf Stream.