Sentences with phrase «glacial maximum about»

«Global sea level was about 125 meters below today's sea level at the last glacial maximum about 20,000 years ago (Fairbanks, 1989).

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 today's.

Not exact matches

But some researchers have argued that the transition from the frigid climatic period known as the Last Glacial Maximum (LGM)-- about 20,000 to 25,000 years ago — to the current warm Holocene Epoch brought habitat changes that killed off the mammoths with little or no help from humans.

The last glacial maximum was about 18,000 years ago, when the Patagonian ice sheet expands to include about 10 meters [33 feet] of global sea level.

That is, during the Last Glacial Maximum the global ocean was about 1 psu saltier than now.

During the late Pleistocene glacial maxima, about two - thirds of the present Alaskan land mass was ice free (Hamilton and Goebel 1999:156).

For example, the uniform lowering of tropical snowline by about 900 meters during the Last Glacial Maximum is generally attributed to cooling [Porter 2001], and indeed provided the first indication that something was wrong with plankton - based estimates of tropical cooling during the glacial Glacial Maximum is generally attributed to cooling [Porter 2001], and indeed provided the first indication that something was wrong with plankton - based estimates of tropical cooling during the glacial glacial period.

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.

The difference between the last glacial maximum (20,000 yrs ago) and today is about 120 meters (400 ft), but the high levels during some of the warmest interglacials were 6 - 9 meters (20 to 30 feet) higher than today.

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.

There were two CLIMAP experiments to reconstruct past climates, one at the Last Glacial Maximum (LGM) 18,000 years ago when sea level was about 120 meters lower than today, and one at the Last Interglacial Maximum (LIM) 125,000 years ago when sea level was about 6 meters higher than today.

[Response: The albedo change, going from last glacial maximum to present (pre-industrial time) was about 3.5 + / -1 W / m ^ 2, whereas CO2 change (including other greenhouse gases) was about 2.6 + / - 0.5), and aerosols about 0.5 + / -1.

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?

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.

A map of sea ice extent at the climax of the Last Glacial Maximum (both perennial and seasonal ice), prepared with the help of a colleague, makes it possible to discuss what genetic and fossil evidence can tell us about the probable effects of glacial conditions on polar bears and ringedGlacial Maximum (both perennial and seasonal ice), prepared with the help of a colleague, makes it possible to discuss what genetic and fossil evidence can tell us about the probable effects of glacial conditions on polar bears and ringedglacial conditions on polar bears and ringed seals.

The last glacial maximum was only about 5 or 6K cooler than present.

Since the end of the Last Glacial Maximum sea levels have risen about 120 meters.

This case appears to be based on recent research taking two different approaches: looking at recent climate changes, and changes during the Last Glacial Maximum (LGM) about 20,000 years ago.

In most cases, these range from about 2 to 4.5 C per doubled CO2 within the context of our current climate — with a most likely value between 2 and 3 C. On the other hand, chapter 9 describes attempts ranging far back into paleoclimatology to relate forcings to temperature change, sometimes directly (with all the attendant uncertainties), and more often by adjusting model parameters to determine the climate sensitivity ranges that allow the models to best simulate data from the past — e.g., the Last Glacial Maximum (LGM).

IPCC: It is very likely that the global warming of 4 °C to 7 °C since the Last Glacial Maximum occurred at an average rate about 10 times slower than the warming of the 20th century.

In the ace ages, CO2 changes from 185 ppm (glacial maximum) to 270 ppm (average interglacial at +1.0 C)-- while temperatures change by about 6.0 C in an average glacial - interglacial transition.

I haven't seen the Hansen paper, but expect that he will be using a somewhat too cold estimate for the Last Glacial Maximum (ie, 6C colder than modern rather than the newer estimate of about 4C).

Such cooling would represent about one - fourth of overall glacial maxima cooling if that overall cooling were − 5 K.

Therefore we can work backward in time to estimate what he reckons atmospheric CO2 would be at the time of the last Ice Age (glacial maximum), a time when global temperatures were about 4 - 6 °C cooler than now.

The last glacial maximum peaked 20,000 years ago at about 8 - 9C lower average planetary temperature than today.