Sentences with phrase «cold glacial periods»

The largest global - scale climate variations in Earth's recent geological past are the ice age cycles (see Learn about... the ice ages), which are cold glacial periods followed by shorter warm periods (see Figure 3).

PS By «stable» I mean that the global temperature has been alternating between warm interglacials and cold glacial periods — but it is stable in not going outside those ranges.

Substantial and correlated changes in marine carbonate (CaCO3) content of oceanic sediments commonly accompany the transitions from cold glacial periods to warm interglacial periods.

Ice sheet models can be run through many glacial cycles (i.e. cold glacial periods and warm interglacial periods).

For example, atmospheric carbon dioxide grew by approximately 30 % during the transition from the most recent cold glacial period, about 20,000 years ago, to the current warm interglacial period; the corresponding rate of decrease in surface ocean pH, driven by geological processes, was approximately 50 times slower than the current rate driven largely by fossil fuel burning.

During the last glacial period, sea level dropped 400 feet as water was tied up in ice, and as we have moved out of the cold glacial period, sea level has recovered.

So perhaps Earth has been as cool a 15 C colder than present Earth, but what mean is don't think it's been more than 20 C cooler [or what I would characterize a Earth which could called a snowball Earth [rather simply what could associate with a colder glacial period].

Not exact matches

The last glacial period spanned from 110,000 to 10,000 years ago; during that time the Earth was colder and glaciers covered significantly more land.

The more intensive variations during glacial periods are due to the greater difference in temperature between the ice - covered polar regions and the Tropics, which produced a more dynamic exchange of warm and cold air masses.

As the glacial period drew to a close and temperatures began to rise, there were two final cold snaps.

The researchers found that during glacial periods when the atmosphere was colder and sea ice was far more extensive, deep ocean waters came to the surface much further north of the Antarctic continent than they do today.

* Circulation changes in the Faeroe - Shetland Channel correlating with cold events during the last glacial period (58 - 10 ka).

...» Meltwater from glacial Lake Agassiz (southwest of Hudson Bay) draining catastrophically into the North Atlantic via Lake Superior and the St. Laurence seaway was once thought to have initiated ocean circulation changes leading to the Younger Dryas cold period.

This article will use the term ice age in the former, glaciological, sense: glacials for colder periods during ice ages and interglacials for the warmer periods.

The Little Ice Age was not a true glacial period, but describes colder climates around the world.

: the fact that the ocean was colder during glacial periods by itself explains only about 10 % of the CO2 change.

If C02 is the largest single contributing factor to the Greenhouse Effect (because supposedly water vapor is only involved as a feedback to primary chemistry involving C02 itself), and C02 lags temperature increases (as has been stated on this very blog), how has the Earth ever returned to colder glacial conditions following periods of warming?

The following is in response to Rayâ s question: What causes the drop in CO2, as the earth cools, from the interglacial warm period to the glacial coldest period?

The planet went from interglacial warm to glacial cold during the Younger Dryas period with cooling for around 1000 years.

The results suggest that warm Atlantic water never ceased to flow into the Nordic seas during the glacial period; inflow at the surface during the Holocene and warm interstadials changed to subsurface and intermediate inflow during cold stadials.

Similarly, a colder climate with generally decreased humidity q O could be closer to the critical threshold, which might be the reason for less - stable monsoon circulations during glacial periods.

Except for MIS 14, the temperature anomalies (relative to the mean temperature of the last millennium) of the coldest levels of all glacial periods range from around -9 to -9.5 °C with CO2 concentrations generally in the range 180 — 190 p.p.m.v..

[1] It began with the end of the cold period known as the Oldest Dryas, and ended abruptly with the onset of the Younger Dryas, a cold period that reduced temperatures back to near - glacial levels within a decade.

The radiation hypothesis beloved by IPCC is not fitting the observations; not for the last 14 years, and not for the past, considering the known warm and cold periods in the past (including glacial and interglacial times).

-- Gleick It's my understanding that the White Earth is colder than the recent glacial periods.

Once a temperature threshold is breached, abrupt events follow due to amplifying feedbacks, even within a few years, examples being (1) freeze events which followed temperature peaks during past interglacial peaks due to influx of cold ice - melt water into the north Atlantic Ocean; (2) the Dansgaard — Oeschger warming events during the last glacial period; (3) the Younger dryas stadial freeze and the Laurentian stadial freeze.

If there was actually glaciation during cold periods, glacial dust might well have blown out to sea, fertilizing large areas and producing a stronger CO2 pump.

During the 800,000 years prior to 1750, atmospheric CO2 varied from 180 ppm during glacial (cold) up to 300 ppm during interglacial (warm) periods.

During a glacial period (ice age) the oceans near both poles are much colder so the amount of heavy oxygen is very small.

During a glacial period, we'd be about 9F colder than today, which would be around 52F.

(Clearly however brief Warm periods can occur during a general glacial retreat and brief cold periods during glacial advance.)

47 Cold periods, Glacial episodes.

A closed blue horizontal line at the top of the graph equates to a period of glacial retreat (warmth) and a closed blue line at foot of graph demonstrates glacier advance (cold)

This is the case in the Little Ice Age, when the lows of all three cycles took place in close succession, contributing to make this the coldest period in the Holocene, bringing it to the brink of triggering a glacial period.

Whether this change in cyclicity means that Earth is heading into still colder climates, or on its way out of this glacial period, I don't know.

So for the past 3 million years the average temperature of the earth hasn't been the warmish 15C of the past 10,000 years of interglacial period but rather the brutal cold 3C of the glacial periods which last ten times as long as the interglacials.

For example, the Greenland ice core data shows that the Younger Dryas cooling event occurred in a 5 year period (Younger Dryas is the name for a climate change from the current interglacial Holocene, warm period, back to the Wisconsin glacial, cold period, that occurred 12,800 yrs ago).

[Also, just to give an idea of the change we are talking about, 5 degrees Celsius might not sound like much, but that is the difference in global average temperature between the coldest period of an ice age and the hottest period of a warm period or «interglacial» in the Earth's glacial history in the modern epoch.]