Sentences with phrase «ice age cycles»

It seems far more likely that volcanic activity and the natural ice age cycles are causing the current, temporary warming trend.

Based just on orbital forcing, and following previous ice age cycles, we are due for a long period of gradual cooling to the next ice age.

I believe he said that it might explain ice age cycles.

Does that argument allow for ice age cycles to occur?

CO2 did come from oceans as they heated up at end of ice age cycles with significant contributions from eurasian swamps as well.

Remember this discussion in now aboot Jupiter / Saturn and any direct linkage with Earth's climate, such that, for instance, Jupiter / Saturn are the causative agent of Earth's 41kyr and 100kyr ice age cycles.

Snyder (2016) uses 61 temperature reconstructions from 59 globally diverse sediment cores and a correlation structure from model simulations of the last glacial maximum to estimate (with uncertainties) the history of global temperature back through the last few dozen ice ages cycles.

According to the standard story, the recent ice age cycles only set in in the Pleistocene because you need ice to amplify the rather small Milankovic forcing and to rectify the seasonal forcing modulations into a long - term signal.

Curiously, the decline in atmospheric oxygen over the past 800,000 years was not accompanied by any significant increase in the average amount of carbon dioxide in the atmosphere, though carbon dioxide concentrations do vary over individual ice age cycles.

But over the years, first as Soviets, then as Russians, and sometimes with help from non-Russians, Zotikov and his colleagues extracted several useful ice cores, including a landmark one that held 420,000 years of climate data, through four full ice age cycles.

The periods considered were mainly the Pleistocene ice age cycles, the LGM and the Pliocene, but Paul Valdes provided some interesting modeling that also included the Oligocene, the Turonian, the Maastrichtian and Eocene, indicating the importance of the base continental configuration, ice sheet position, and ocean circulation for sensitivity.

Dr. Archer has worked on the ongoing mystery of the low atmospheric CO2 concentration during glacial time 20,000 years ago, and on the fate of fossil fuel CO2 on geologic time scales in the future, and its impact on future ice age cycles, ocean methane hydrate decomposition, and coral reefs.

When ice age cycles are concerned Milankovitch cycles and feedback through CO2 are surely involved, but — Milankovitch cycles are weak, at least on global level.

The 150 Myr Ice Age cycle has produced four Ice Ages in the last 450 million years.

Ice Age cycles once invoked, over ride the smaller influences of level 2 and 3.

Furthermore, because the regression is being defined over ice age cycles where the biggest changes are related to the (now disappeared) North American and Fenno - Scandanavian ice sheets, the regression might well be much less for situations where only Greenland and West Antarctica are «in play».

How much it might vary is very difficult to tell, but for instance, it is clear that from the Pliocene to the Quaternary (the last ~ 2,5 million years of ice age cycles), the climate has become more sensitive to orbital forcing.

Most examining climate see long term natural cycles on larger scales more like the 100,000 year ice age cycles (and that is what I am referring to):

The bottom line is that you can't estimate Earth System Sensitivity solely from correlations over ice age cycles, no matter how well put together the temperature data set is.

[Response: Errr... there is no demonstrated rise in volcanic activity, the warming of the ocean is much larger near the surface, the KT impact event has nothing to do with rising CO2 today, natural ice age cycles would be leading to a cooling at the present if large enough to be noticeable, and water vapour is not ignored!

Snyder (2016) uses 61 temperature reconstructions from 59 globally diverse sediment cores and a correlation structure from model simulations of the last glacial maximum to estimate (with uncertainties) the history of global temperature back through the last few dozen ice ages cycles.

If feedbacks from water vapour and clouds are negative or zero, then the changes required to cause such swings in temperature are huge - equivalent to a change in the suns strength of 10 % for the recent ice age cycles, and possibly upto 30 % for the mid-cretaceous maximum, 100 million years ago.

The rubbish comment noted that geomagnetic field intensity changes do not correlate with the ice age cycles.

In a bit more detail, people were aware of various forcing mechanisms — the ice age cycle; CO2 warming; aerosol cooling — but didn't know which would be dominant in the near future.

And IIRC Arrhenius theorized (and stated that this was the motivation for his CO2 studies) that the ice age cycle was caused in full by variations in atmospheric CO2; an idea that has not stood the test of time.

The current climate change, unlike the iced age cycles of the last million years or so, started with CO2 forcing instead of orbital forcing.