Sentences with phrase «glacial maximum in»

I'm not sure you want to go there... Remember the glacial maximum in North America was only 18,000 years ago and you could make some simple calculation about the volume of ice involved and how quickly it vanished.

During the Last Glacial Maximum in the Pleistocene Epoch, approximately 26,000 years ago, many areas and islands in Asia were connected.

Not exact matches

«In fact from the end of the Last Glacial Maximum some 19,000 years ago, its genetic component reappeared in SpaiIn fact from the end of the Last Glacial Maximum some 19,000 years ago, its genetic component reappeared in Spaiin Spain.

Before the corridor closed, prior to the last glacial maximum, they moved freely up and down between the ice - free regions in the north and grasslands south of the ice sheets.

«Ice age bison fossils shed light on early human migrations in North America: Study dates the first movements of bison through an ice - free corridor that opened between the ice sheets after the last glacial maximum.»

Drawing on recent findings from archaeology, genetics, and the environmental sciences, the author provides a region - by - region account of the transformations of human populations in the 15 millennia following the Last Glacial Maximum.

In contrast, in slightly wetter parts of Mongolia the largest glaciers did date from the ice age but reached their maximum lengths tens of thousands of years earlier in the glacial period rather than at its culmination, around 20,000 years ago, when glaciers around most of the planet peakeIn contrast, in slightly wetter parts of Mongolia the largest glaciers did date from the ice age but reached their maximum lengths tens of thousands of years earlier in the glacial period rather than at its culmination, around 20,000 years ago, when glaciers around most of the planet peakein slightly wetter parts of Mongolia the largest glaciers did date from the ice age but reached their maximum lengths tens of thousands of years earlier in the glacial period rather than at its culmination, around 20,000 years ago, when glaciers around most of the planet peakein the glacial period rather than at its culmination, around 20,000 years ago, when glaciers around most of the planet peaked.

The sediment cores used in this study cover a period when the planet went through many climate cycles driven by variations in Earth's orbit, from extreme glacial periods such as the Last Glacial Maximum about 20,000 years ago, when massive ice sheets covered the northern parts of Europe and North America, to relatively warm interglacial periods with climates more like tglacial periods such as the Last Glacial Maximum about 20,000 years ago, when massive ice sheets covered the northern parts of Europe and North America, to relatively warm interglacial periods with climates more like tGlacial Maximum about 20,000 years ago, when massive ice sheets covered the northern parts of Europe and North America, to relatively warm interglacial periods with climates more like today's.

Bar - Yosef points out that, at the time, Earth was in the clutches of the Last Glacial Maximum, the height of the last ice age.

During the Last Glacial Maximum when the Earth was much colder, closed - basin lakes in currently dry parts of western North America, the Middle East and South America were much larger than they are now, as evidenced by radiocarbon dating and other testing of their ancient shorelines.

«Interestingly, the past land connections during the Last Glacial Maximum are more important in explaining the existing ant community patterns, than the way land is configured now,» Wepfer said.

The discovery that the oldest pots in the world were made in China around the time of the Last Glacial Maximum suggests that might be the case.

This doesn't change for thousands of years as these populations remain in apparent isolation in the shelter of the mountains — possibly cut off from other major ancestral populations for as long as 15,000 years — until migrations began again as the Glacial Maximum recedes, and the Yamnaya culture ultimately emerges.

This date is consistent, however, with the expansion of O. rufipogon populations after the Last Glacial Maximum ∼ 18 ka and archeological evidence for early wild rice management in China.

During the last glacial maximum, Wiens explained, the weight of the ice bent the Earth's crust, forcing the plastic rock in the upper layer of the Earth's mantle to flow away from the loaded region.

We have discussed climate sensitivity frequently in previous posts and we have often referred to the constraints on its range that can be derived from paleo - climates, particularly the last glacial maximum (LGM).

Bentley, M.J., and Anderson, J.B., 1998, Glacial and Marine Geological Evidence for the Extent of Grounded Ice in the Weddell Sea - Antarctic Peninsula Region During the Last Glacial Maximum: Antarctic Science, v. 10, (3), p. 307 - 323Berkman, P.A. and Ku, T. - H.

At the Last Glacial Maximum, palaeo - ice streams extended to the shelf edge in West Antarctica and in the Antarctic Peninsula, but in East Antarctica they usually were restricted to the mid-outer shelf [44].

Distinguishing subglacial till and glacial marine diamictons in the western Ross Sea, Antarctica: Implications for last glacial maximum grounding line.

Qualitatively, the slow ventilation is consistent with very saline and very cold deep waters reconstructed for the last glacial maximum (Adkins et al., 2002), as well as low glacial stable carbon isotope ratios (13C / 12C) in the deep South Atlantic.

This type of chaotic pattern of rapidly changing land, ice, saltwater and freshwater has been proposed as the likely model for the Baltic and Scandinavian regions, as well as much of central North America at the end of the last glacial maximum, with the present - day coastlines only being achieved in the last few millennia of prehistory.

On the studies of sensitivity based on the last glacial maximum, what reduction in solar forcing is used based on the increased Albedo of the ice - sheets, snow and desert.

Using Mg / Ca paleothermometry from the planktonic foraminifera Globigerinoides ruber from the past 500 k.y. at Ocean Drilling Program (ODP) Site 871 in the western Pacific warm pool, we estimate the tropical Pacific climate sensitivity parameter (λ) to be 0.94 — 1.06 °C (W m − 2) − 1, higher than that predicted by model simulations of the Last Glacial Maximum or by models of doubled greenhouse gas concentration forcing.

Using the change in temperature from the last glacial maximum as a ruler, if the change in temperature from that is near 6 Kelvin, then 2 K warmer than pre-industrial means a certain level of effects.

[2] The only current ice sheets are in Antarctica and Greenland; during the last glacial period at Last Glacial Maximum (LGM) the Laurentide ice sheet covered much of North America, the Weichselian ice sheet covered northern Europe and the Patagonian Ice Sheet covered southern South Aglacial period at Last Glacial Maximum (LGM) the Laurentide ice sheet covered much of North America, the Weichselian ice sheet covered northern Europe and the Patagonian Ice Sheet covered southern South AGlacial Maximum (LGM) the Laurentide ice sheet covered much of North America, the Weichselian ice sheet covered northern Europe and the Patagonian Ice Sheet covered southern South America.

26 Paul W asked, «On the studies of sensitivity based on the last glacial maximum, what reduction in solar forcing is used based on the increased Albedo of the ice - sheets, snow and desert.

For instance, Köhler et al used an estimate of the cooling at the Last Glacial Maximum of 5.8 ± 1.4 ºC, but a recent update from Annan and Hargreaves and used in the Hargreaves et al estimate is 4.0 ± 0.8 ºC which would translate into a lower CS value in the Köhler et al calculation (roughly 1.1 — 3.3 ºC, with a most likely value near 2.0 ºC).

In contrast, the much more expansive ice volume maxima (equivalently, sea level minima) during a glacial maximum is more defined.

We have discussed climate sensitivity frequently in previous posts and we have often referred to the constraints on its range that can be derived from paleo - climates, particularly the last glacial maximum (LGM).

The world warmed around 5 °C in 10,000 years since the last glacial maximum — that's 0.005 °C per decade on average.

The results of these simulations show that dust − climate feedbacks, perhaps set off by orbital forcing, push the system in and out of extreme cold conditions such as glacial maxima.

Sea level dropped during the last glacial maximum, but there was no ice sheet in Siberia, so the surface was exposed to the really cold atmosphere, and the ground froze to a depth of ~ 1.5 km.

Without our use of fossil fuels, we should be descending into another glacial maximum — albeit slowly, over tens of thousands of years (the pace of natural global climate change in the Pleistocene).

Maybe you would find our recent manuscript interesting, in which we use an efficiently - generated ensemble of a state - of - the - art GCM, tuned to present - day climate and validated (tested against out - of - sample data) with simulations of the Last Glacial Maximum.

For instance, for the Last Glacial Maximum, model - data mis - matches highlighted by Rind and Peteet (1985) for the tropical sea surface temperatures, have subsequently been more or less resolved in favour of the models.

The mid-Holocene (6000 years ago) and Last Glacial Maximum (~ 20,000 years ago) are also attractive targets of model validation, and while some successes have been noted (i.e. Joussaume et al, 1999, Rind and Peteet, 1985) there is still some uncertainty in the forcings and response.

Using Mg / Ca paleothermometry from the planktonic foraminifera Globigerinoides ruber from the past 500 k.y. at Ocean Drilling Program (ODP) Site 871 in the western Pacific warm pool, we estimate the tropical Pacific climate sensitivity parameter (λ) to be 0.94 — 1.06 °C (W m − 2) − 1, higher than that predicted by model simulations of the Last Glacial Maximum or by models of doubled greenhouse gas concentration forcing.

[Response: the Milankovitch timescale is long and the forcing barely varies due to orbital changes over 100 years so no, they aren't included (they would be for people modelling the last glacial maximum); solar forcing is modelled by change in total solar irradiance (probably as a total number; not sure if changes at different wavelengths are included)-- William]

The research drew lessons from paleoclimate studies of the Last Glacial Maximum, the cold peak of the last ice age, that relate to the extent of warmth possible in an era of accumulating greenhouse gases:

Using the change in temperature from the last glacial maximum as a ruler, if the change in temperature from that is near 6 Kelvin, then 2 K warmer than pre-industrial means a certain level of effects.

In particular, Annan and Hargreaves (2006) used a Bayesian statistical approach that combines information from both 20th century observations and from last glacial maximum data to produce an estimate of climate sensitivity that is much better constrained than by either set of observations alone (see our post on this, here).

The most obvious D - O (Dansgaard - Oechsger) events in the vicinity of the LGM (Last Glacial Maximum, 20,000 years ago) represent extreme examples of this scenario.

On the studies of sensitivity based on the last glacial maximum, what reduction in solar forcing is used based on the increased Albedo of the ice - sheets, snow and desert.

For instance, Köhler et al used an estimate of the cooling at the Last Glacial Maximum of 5.8 ± 1.4 ºC, but a recent update from Annan and Hargreaves and used in the Hargreaves et al estimate is 4.0 ± 0.8 ºC which would translate into a lower CS value in the Köhler et al calculation (roughly 1.1 — 3.3 ºC, with a most likely value near 2.0 ºC).

We've had both situations in the past — «Amsterdam» under ice about 20,000 years ago at the last glacial maximum, and «Amsterdam» under water in the Pliocene, 3 million years ago, when CO2 and sea level were higher than today.

In terms of the comments about the Holocene record, etc, and Gavin's saying that there is «no evidence» of such methane burps then: first, let us all also acknowledge that some of the world's major paleoclimate and methane experts HAVE seen evidence of exactly that [i.e., Nisbet, Have sudden large releases of methane from geological reservoirs occurred since the Last Glacial Maximum, and could such releases occur again?

You will notice the large difference in circulation patterns between «Present day» and «Last Glacial Maximum».

When a large ice sheet grows in a location, such as happened at the Last Glacial Maximum (LGM) about 20,000 years ago, the weight of the ice deforms the solid Earth beneath it.

The load of ice in the area during the last glacial maximum would have added significant pressure to the crust below.

However, going back several centuries and reconstructing the entire process of glacier shrinkage from the «little ice age» — the last glacial maximum occurred in this part of the Andes between the 17th and 18th centuries — Andean glaciers began to retreat around AD1730 - 50.