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Glaciares Pirenaicos: seguimiento y temas relacionados

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Baixriberenc:
si lo creo, afirmo que la temperatura es mas de un grado mas alta que hace 200 años en los pirineos, eso seguro y que no sean 4 o 5 grados, la nieve del propio glaciar refleja el 90% de luz solar provocando que los rayos no calienten el suelo generando a su vez mas frio, por lo que debido a este efecto y a los frios de la epoca la temperatura alli donde los glaciares eran extensos podria ser de 4 grados mas baja que ahora, o tal vez no, tal vez con las mismas temperaturas que hay ahora pero con muchas mas precipitaciones en hinvierno...como se si es debido a la falta de precipitacion o a la falta de frio? no lo se... No sabemos como afecta un grado de calentamiento global a una zona especifica, segun los expertos ese calientamento global traeria frio por culpa del desviamiento de la corriente del golfo, no obstante los pirineos se derriten sobre calentarse el globo 1 grado seguimos perdiendo glaciar, la verdad es que hay opiniones para todos los gustos, y yo no me fio de casi ninguna jaja.

habichuela:
Sobre glaciares:

Stone Age trade routes yield spectacular finds on alpine pass - clothes, weapons and devices also from Roman time and the Middle Ages

Holger Kroker scientist of the archaeological service Berne found among other things a Roman booklet (garb latch):
In the hot summer of 2003 two wanderers from the Swiss Thun did not trust their eyes. They stood at the edge of an icefield at the Schnidejoch above Lenk, when they discovered a birchbark arrow-quiver. A dating with the archaeological service of the canton Berne showed that the birchbark is nearly 5000 years old. Meanwhile the Bernese archaeologist searched the area thoroughly and found some evidence for a much-used connection between that Bernese upper country and north Italy. The glacier between the today’s ski place Lenk in the north and Sitten, the principal place in the canton Wallis, had released pieces of find from four different epochs. For the archaeologists, the discovery is of comparable importance to Oetzi, the South Tirol glacier corpse.

"Naturally, Oetzi is more sensational", says Peter Suter, Leader of the department of prehistory and early history with the archaeological service in Berne. "However for historical research, these finds from several centuries are just as important." Because they represent not only a snapshot, but as it were a diagram of the settlement and climatic history in the central Alps. The oldest finds are clothing remnants and articles of equipment dated from the Late Stone Age and the epoch between 2800 and 2500 BC. Among them are a birchbark arrow-quiver, some stone arrowheads as well as fragments of Stone Age leather shoes and trousers. The researchers found also particles of human skin as well as skin remnants, which may come from a horse. "One asks oneself, what was a horse doing there?", so Peter Suter.

If DNA investigations confirm the fact that it actually comes from a horse, it could show a completely early form of domestication. A second group of finds originate from the Bronze Age between 2000 and 1750 BC, among them bronze aristocracy and remnants of a splinter box, which obviously served for the transport of goods. From Roman times, a Wollguertel, numerous shoe nails were held together and a booklet from the 1st or early 2nd century AD were found with the dresses. The youngest find is part of a shoe dated to the 14/15th Century.

Afterwards the pass over the Schnidejoch was locked in again by ice and snow until 2003. "These finds are so important, because they reflect the on and starting from the Vergletscherung in the past 10,000 years that we also know from other sources", stressed Peter Suter. For instance from the drill cores of the Greenland glaciers, which serve as climatic archives. For the times from which the finds originate from the Schnidejoch, these drill cores show clear references to warm periods.

Also investigations of researchers of the ETH Zurich on the apron of the Unteraargletschers in the upper Bernese country resulted in strongly varying temperatures in the Alps, into whose attendants the glaciers advanced at times and retreated at times. "Scientific and archaeological findings fit together outstandingly", says Suter. From climatic research, it is well-known that in Europe between the 3rd Millenium and 1750 BC, a mild climate prevailed. The average summer temperatures might have been at that time for 0.5 to two degrees than today. As consequence the pass was passable over the 2756 meters high Schnidejoch in the summer and represented together with that 2000 meters high Simplonpass the shortest connection between north Italy and the Bernese upper country. The large number of finds is for the Bernese experts evidence of traffic movement at that time.

Later climatic degradation in Europe let the glaciers advance again and blocked the way starting from 850 BC to Roman times, the ice masses releasing the pass starting from approximately 150 BC. There are remnants of Roman settlements in the upper Bernese country: a whole row about a temple district in Thun from the first until the third century AD. Also few hundred meters underneath the pass, one found remainders of a Roman lodging. "We always asked ourselves, where it continued, reports from there" Peter Suter, "We know now we that the way led across the Schnidejoch." A climatic degradation accompanied the fall of the Roman realm, so that the pass between Lenk and Sitten became blocked again. In the late Middle Ages, the glaciers withdrew and opened the way for few centuries, but since the Little Ice Age, those again remained blocked from the middle of the 16th to the 19th Century. Only the summer of 2003 changed that and opened the way over the Schnidejoch again. In the meantime, even modern city people can move on the traces of their Late Stone Age ancestors. "The moving way", thus Peter Suter, "was marked in the past summer."

QuiMax:
Perdona, tienes el vinculo?

habichuela:
Aquí lo tienes:

http://www.climateaudit.org/?p=434

esto no ha salido nunca en la sección de ciencia de El Mundo, claro, porque alguna teoría del cataclismo se caería, al menos en lo que a cierta fenomenología y sus causas se refiere.

saludos

Gabimeteo:
Sueca, los glaciares de los Alpes estan retrocediendo a lo bestia, no hay mas que comparar fotos, o mejor verlo in situ. Es patente a mas no poder. No se de donde sacas la info de que se mantienen.
Algunos casos de glaciares andinos o de alaska que estan avanzando se deben a cambios en el deslizamiento sobre el suelo y paredes, al perder permafrost. El suelo se vuelve mas deslizante, por lo que el glaciar avanza en longitud, aunque este perdiendo gran cantidad de masa.

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