Sentences with phrase «many past ice ages»

The resulting lower atmospheric CO2, the argument goes, would mean lower temperatures, suggesting that the mechanism was at least partially responsible for triggering past ice ages.

This line marks a deep ocean channel that remained water - filled even during past ice ages, when sea levels saw channels between other islands in the region dry out.

And did airborne iron cause past ice ages?

Costa and her colleagues wanted to find out if the dusty atmosphere also stimulated CO2 sequestration in other ocean basins during the past ice age.

As Weir points out, it likely owes its survival as a species on being geographically isolated from its parental species at some point during a past ice age when rainforest coverage contracted, and wide rivers formed natural barriers.

Visible from space, the hole is a relic of past ice ages and was made famous by the oceanographer Jacques - Yves Cousteau.

Like other sea - holes or «vertical caves,» the Great Blue Hole in Belize's Lighthouse Reef actually formed on dry land, during a past ice age when the sea level was a lot lower than it is today.

During some of the warm periods between past ice ages, it has been as warm as, or warmer than, it is today.

How do you think climate scientists model and otherwise study past ice ages if they ignore their cause?

For example, how are the causes of past ice ages relevant to that question?

However, our fortune would last much longer than that: the Milankovitch cycles can be calculated over millions of years with astronomical precision (and incidentally be used to predict the beginning of all the past ice ages), and according to that, the next major climate change would arrive only in about 50,000 years.

Seafloor sediments show that during past ice ages, more iron - rich dust blew from chilly, barren landmasses into the oceans, apparently producing more algae in these areas and, presumably, a natural cooling effect.

Rohling et al. (2013) provide a good overview on what we know about rates of sea level rise in the Holocene, past ice ages and interglacials:

The past ice ages were all caused by something very specific, right?

Does the person who says were just seeing a natural trend here similar to past ice ages and warming trends.....

The different patterns can be used to hunt for now - disappeared glaciers from past ice ages.

If you can't be sure about CO2 - temp relation in Late Ordovician, you can't be sure either at any other past ice age.

Many past ice ages were caused by... 1.

As massive ice sheets retreated during past ice ages, their weight on the land below lifted and the land rebounded.

Yet climate did change, as proven by past ice ages.

The paleoclimate record combined with global models shows past ice ages as well as periods even warmer than today.

Not exact matches

They note past ages that have been equally warm or warmer without human influence, to say nothing of repeating patterns of climate change like ice ages (though I've met one of James Hansen's computer modelers who told me with sincere conviction that there would not be another ice age).

The real purpose of myth (e.g. the creation stories) is not to give an account of what actually happened in the past, or what may happen in the future (e.g. another ice age), but to convey a particular understanding of human life.

Explore the Ice Age with hands - on glacier demonstrations and activities, as well as real geologic clues to New England's icy past (Cambridge)

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.

Over the past 40 years, radar imagery has revealed around 150 freshwater lakes of various sizes and ages beneath the massive Antarctic ice sheet.

The observed activity of 288P also reveals information about its past, notes Agarwal: «Surface ice can not survive in the asteroid belt for the age of the Solar System but can be protected for billions of years by a refractory dust mantle, only a few metres thick.»

The discovery of ice ages in the distant past proved that climate could change radically over the entire globe, which seemed vastly beyond anything mere humans could provoke.

In fact, for temperature the major step toward the ice ages that have characterised the past two to three million years was a cooling event at 2.7 million years ago, but for ice - volume the crucial step was the development of the first intense ice age at around 2.15 million years ago.

These big ice sheets have frozen and melted many times in the past (producing ice ages with low sea levels and warm periods with high sea levels).

Earth is thought to have shifted in and out of ice ages every 100,000 years or so during the past 800,000 years, but there is evidence that such a shift took place every 40,000 years prior to that time.

It provides new insight into the climatic relationships that caused the development of major ice - age cycles during the past two million years.

The research takes as its desired stable state the Holocene epoch, the 10,000 years since the last ice age during which human civilization has flourished, and attempts to identify the key variables that might push planetary cycles past safe thresholds.

The overall retreat of several kilometers that has occurred over the past 20,000 years was interrupted by a stillstand or a re-advance of several hundred years at the beginning of the ACR, and then by increasingly minor glacial episodes at the end of the YD, at the beginning of the Holocene (around 10,000 years ago) and during the Little Ice Age (13th to 19th centuries).

We present a synthesis of decadally resolved proxy temperature records from poleward of 60 ° N covering the past 2000 years, which indicates that a pervasive cooling in progress 2000 years ago continued through the Middle Ages and into the Little Ice Age.

On land, the capacity of animals to carry nutrients away from concentrated «hotspots,» the team writes, has plummeted to eight percent of what it was in the past — before the extinction of some 150 species of mammal «megafauna» at the end of the last ice age.

The local diversity and unique geologic history (covered by neither glaciers nor oceans for the past 225 million years, the Ozarks provided refuge for migrating species during the Ice Age) explain the richness of the lichens here: some 600 named species, along with 30 recently discovered ones awaiting their official designation.

Look at the great ice ages of the past.

Humans have influenced nature since as early as the Ice Age, and over the past century our impact has become even greater with our many new technologies and a growing world population.

There have been several such transitions in the past, but one of the largest and most dramatic transitions happened at the end of the last Ice Age.

In the early 1990s, they re-created a history of the Earth's atmosphere throughout the past 400,000 years — a record of our planet's air during the past four ice ages.

See the RealClimate discussions of the Little Ice Age and Medieval Warm Period for explanations of why both the Viking colonization of Greenland and the freezing of the River Thames actually tells us relatively little about past climate change.

«The climate reconstructions for the past 2,000 years have led to a simplistic picture of a Medieval Warm Period and a Little Ice Age.

The WAIS Divide deep ice core WD2014 chronology — Part 1: Methane synchronization (68 - 31 ka BP) and the gas age — ice age difference Climate of the Past, 11, 153 - 173

Indeed, the main quandary faced by climate scientists is how to estimate climate sensitivity from the Little Ice Age or Medieval Warm Period, at all, given the relative small forcings over the past 1000 years, and the substantial uncertainties in both the forcings and the temperature changes.

The WAIS Divide deep ice core WD2014 chronology — Part 1: Methane synchronization (68 - 31 ka BP) and the gas age — ice age difference Climate of the Past, 11, 153 - 173 \ nBuizert, C., and 15 others.

Re 92 and 105: First I just want to reitterate more generally what 105 said — Milankovitch cycles have had climate signals, in ice ages or otherwise, — well probably ever since the Moon formed, although the signal from times past will not always reach us, but I've read of evidence of Milankovitch precession cycle forcing of monsoons in lakes in Pangea (PS over geologic time the periods of some of the Milankovitch cycles have changed as the Moon recedes from the Earth due to tides).

Calvert Island, in particular, is among the few places worldwide with a sea level that has remained relatively stable since the last ice age, a boon for scientists looking to study how people have lived for the past 15,000 years.

I have heard it stated in the past that if the Gulf Stream shut down, it would lead to another ice age.

We calculate the WD gas age - ice age difference (Delta age) using a combination of firn densification modeling, ice - flow modeling, and a data set of d15N - N2, a proxy for past firn column thickness.