Arthur C

A notable Austrian contribution to the literature comes from Kreichgauer (1902), who writes: “From the time ice ages were discovered, new hypotheses have constantly been put forward to explain their connection with known climatic factors. The most obvious assumption, that the Earth's axis had shifted its direction to such an extent that the poles fell into the center of the respective glaciation, found many supporters. While assessing the climatic conditions in detail is provisionally impossible, two major aspects can nevertheless be gained for the Diluvium by observing them, which make themselves felt quite clearly. a) The signature of the overall North Atlantic Diluvium is the cold; its dominance was interrupted by a major retreat of the glaciers, during which approximately today's conditions had set in. b) In Siberia, on the contrary, features of greater warmth predominate; a time similar to today's, or colder, seems to have preceded the Diluvium. Important for our subject is the mutual relationship between the body of the Earth and the Earth's axis. A change in this respect would indeed result in an altered position of all points of the Earth's surface relative to the sun…without the direction of the rotational axis in space, and thus likewise that of the celestial poles, needing to be changed. If I push a long needle through the axis of symmetry of an apple, I can make the apple rotate around this axis—imagine the direction of the needle to be unchangeable, but the apple to be impaled on different diameters of itself; by this, the relationship of the parts of the apple to the rotational axis becomes ever different. The situation is similar with the axis changes within the Earth. If one shifts the Earth against the fixed axis so that it is, as it were, impaled in always different directions, then it is clear that while the climates on Earth in relation to the axis remain unchanged, always different points of the Earth's surface would come near the poles or under the equator. This is what the ice ages seem to indicate. The well-known Italian astronomer Schiaparelli carried out highly complicated mathematical investigations and showed how these parts would have to behave under different cases relative to the rotational axis imagined as approximately fixed in space. For the simplest case, that the Earth consists of a relatively thin crust and a fluid core, the result is immediately clear: purely internal forces can cause shifts of the two parts in space with an almost unchanged axis, and thus bring different points near the poles and likewise guide them under the equator line. Such displacements are, regardless of the opposing resistance, no more conspicuous than the movement of a ship on the ocean; indeed, purely internal forces act directly on this as well.” The author presents a unified mechanical theory of Earth's shape and gravity. Rotation generates centrifugal force, an expression of inertia where each mass particle tends to continue in a straight, tangential line—which acts outward at the equator and diminishes toward the poles. The rotating Earth responds by redistributing mass equatorward to build up a 21.3 km equatorial bulge, or “Schubring,” governed by hydrostatic equilibrium. This resulting oblate shape directly alters gravity’s magnitude and distorts its direction by latitude, causing the local vertical to deviate from the planet's geometric center by a maximum of 11.5arcminutes at the 45th parallel. He further enforces the intermediate axis theorem: three mutually perpendicular principal axes of inertia passing through its center of gravity, around which it can rotate as smoothly as a perfect sphere. Rotation around either of the first two axes, defined by their contrasting structural orientations and rotational resistances, results in a stable equilibrium. However, "The third takes a middle position between the two others with respect to resistance; in the elliptical disc it would be the minor axis. Analytical mechanics now establishes the important theorem that the equilibrium of forces is stable only in the first and second case, but labile in the third; that is, if one disturbs the body slightly while it rotates around the first or second axis, this has little influence. In the third case, however, the slightest shock would suffice to completely destroy the peace of the rotation." This inherent instability means that internal mass imbalances can dynamically drive a shifting lithosphere: “The force described in the last sections is obviously capable of bringing about a displacement of the crust…the displacement sometimes also proceeded much more rapidly, especially since the end of the last Atlantic Ice Age, which may have been 8,000 to 10,000 years ago. At least the finds of very numerous, well-preserved remains of large mammals in northernmost Siberia are favorable to the hypothesis of a rapid displacement at that time.“ The behavior of the pivot points in his model is established: the surface phenomena point with certainty to a rotation of the outer crust around two fixed locations. He determines these locations from the origin of the shifting forces, placing the pivot points "approximately at 135° east and 45° west of Greenwich, roughly in the West Indian and East Indian island seas. From the 135th meridian circle, together with the equator, four spherical triangles are bounded.” Finally, he shows that the wandering of the pole is understandable from geological processes: “For this it is necessary to mention a process that has periodically intervened deeply in the development of the Earth's crust, namely the far-reaching marine transgressions”, citing (Penck, II, 638 to 640.) "Not only uplifted coral reefs, but beneath them juvenile deep-sea formations have also been found, so that in all cases it is possible to demonstrate that even in recent times a deeper sea occupied the place of the island. Beneath the reef limestone, which covers Barbados to a height of 300 meters, lies the Radiolarian earth described by Ehrenberg, which tends to form only at great depths, and beneath that follow dark sandy clays and sandstones of indeterminate age." . . . . On the Solomon Islands, "under young coral limestones up to a sea-level height of 300 meters, marl formations occur whose Foraminifera fauna is still found today in the surrounding seas at a depth of 1800–3700 meters. . . . On the Nicobars there is a Radiolarian earth which, according to Haeckel, originates, like that of Barbados, from more than 3700 meters depth.” Ultimately, the physical and empirical lines of evidence converge to validate this dynamic model of planetary rotation. As regards the Ice Ages and the organisms, the book shows that a “great, indeed decisive, significance [lies] in the pursuit of the thread running through the lines of evidence which must be [uncovered] for the more recent Earth history.” By tracking paleoclimatic and fossil records, “one can sufficiently monitor the displacement at individual geological moments” to fully grasp this shifting planetary system. “Die Äquatorfrage in der Geologie” by Kreichgauer, Damian (1902) Lehrer der Mineralogie und Geologie (Teacher of Geology and Mineral physics) Mödling (Niederösterreich)-[ coincidentally-Tami's place of birth] archive.org/details/dieaquat…

Ewing and Donn (1956) identified repeated alternations between glacial and interglacial stages throughout the Pleistocene epoch. On the question of the most recent glacial termination, they drew on a substantial body of sediment core evidence gathered across the preceding two decades. Faunal studies from equatorial Atlantic cores, Gulf of Mexico sites, and Caribbean Sea samples all pointed to a single, well-marked transition. Radiocarbon measurements confirmed that the characteristic break marking a change from cold to warm pelagic fauna occurred ≈11,000 years ago. A 1960 paper by Broecker et al. and colleagues provided a sweeping empirical corroboration of precisely this picture. Their study compiled evidence from geographically isolated systems, spanning the Atlantic Ocean, the Caribbean, the Great Basin of North America, and northwestern Europe, and found that in each case the data pointed to the same moment. Surface ocean temperatures in the Atlantic increased by several degrees centigrade, and pollen profiles from northwestern Europe indicated a pronounced warm period coinciding with all of these changes. In each case, radiocarbon dating suggested that the changes occurred in a short timeframe, converging on the same moment identified by Ewing and Donn. The Broecker team concluded that "certainly if the abruptness of such a major change in world climate can be firmly established it will be of the utmost importance that acceptable theories are able to account for it." Broecker's study of Atlantic core data showed with particular precision that the faunal transition in surface ocean temperatures had a midpoint within approximately 300 years of 11,000 years ago. The stagnation of the Cariaco Trench, documented by the abrupt appearance of anaerobic sediment above an older oxidized clay layer, was similarly dated to within 300 years of that moment. The overall picture, drawn from independent lines of physical, biological, and chemical evidence, was one of a rapid, globally synchronized reorganization of climate. Where Broecker and colleagues documented the speed and geographic reach of this transition, Ewing and Donn had earlier addressed the deeper question of why glacial conditions arose in the first place. Their proposed answer drew on the following argument, presented here in their own words: "Reconsideration of the hypothesis of pole-wandering. Following the recognition of the extent and distribution of Pleistocene glaciers, many scientists sought an explanation of glacial climates in terms of major shifts in the positions of the poles. Much of the early work was summarized in 1883 by Hann, who believed that great secular changes in climate could only be accomplished by changes in the earth's axis of rotation. Kelvin and other physicists demonstrated that significant pole shifts would be impossible in view of the accepted evidence for high rigidity of the earth, thereby directing most subsequent studies toward alternative explanations. In recent years attention has again been directed toward this hypothesis as it became clear that the earth could not be considered as a completely rigid body. Vening Meinesz assumed a pole shift of many degrees as the basis of his explanation of the major fracture pattern of the earth's crust. Runcorn indicated that the earth's surface could undergo large displacements relative to the interior as a result of convection currents. In considering the direction of magnetic fields indicated by studies of paleomagnetism, Runcorn believed that the variation in these fields could be fully explained by pole wandering. The possibility that adequate forces exist to produce relative movement between the earth's surface and the interior has led us to reopen the question of the effects of pole wandering on secular changes in climate. It should be noted that the poles wander, according to present conception, in a relative sense. The differential movement between an outer shell and the interior results in different points on the surface assuming the positions of the poles. Climatic consequences of pole migration. The poles are presently located in positions of extreme thermal isolation, in marked contrast to the conditions that would prevail if both were in the open ocean. If the North Pole were located in the North Pacific (for example, 35°N and 180°W) and the South Pole at the antipodes of this, in the South Atlantic Ocean, the free interchange of water with the polar regions would preclude formation of polar ice caps. The free interchange would further tend to equalize temperature extremes both geographically and seasonally. A resulting weak and uniform latitudinal temperature gradient would occur, in contrast to the present zonality. This kind of climate must have prevailed between the Permian and Pleistocene glaciations (and probably during the long intervals between other glacial periods), according to inferences made from the geologic record by all authorities. Milankovitch, Köppen, and Creer et al. have all placed the North Pole in the North Pacific Ocean for a long interval beginning with the Cambrian. Although Milankovitch gave no dating, the other investigators estimated that the pole arrived in the Arctic Ocean during the Tertiary. On the basis of the worldwide distribution of corals of various ages, T. H. Y. Ma concluded that sudden displacements of the solid earth shell with respect to the interior occurred. He also located pre-Cretaceous pole positions at distances of more than 90 degrees from their present positions in order to reconcile the fossil record with the appropriate climate, and concluded that abrupt shifts of the earth's crust…carried the poles to their present locations.” Lastly, Ewing and Donn note a long-recognized but puzzling feature of the Pleistocene sea level record: elevated beaches around the world, sometimes reaching heights of approximately 100 meters. Both studies hint at a framework straining the limits of uniformitarianism, suggesting that the boundary between gradual process and catastrophic reorganization may be less firm than the prevailing consensus cared to admit. A Theory of Ice Ages Maurice Ewing and William L. Donn (1956) science.org/doi/10.1126/scie… Evidence for an Abrupt Change in Climate Close to 11,000 Years Ago Broecker et al. (1960) earth.geology.yale.edu/~ajs/…