Ice age
hideThe general term "ice age" or, more precisely, "glacial age" denotes a geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in an expansion of continental ice sheets, polar ice sheets and alpine glaciers. Within a long-term ice age, individual pulses of extra cold climate are termed "glaciations". Glaciologically, ice age implies the presence of extensive ice sheets in the northern and southern hemispheres; by this definition we are still in an ice age (because the Greenland and Antarctic ice sheets still exist).
More colloquially, when speaking of the last few thousand years, "the" ice age refers to the most recent colder period (or freezing period) with extensive ice sheets over the North American and Eurasian continents: in this sense, the most recent ice age peaked, in its Last Glacial Maximum about 20,000 years ago. 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.
For more information about Ice age, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with ice age
Critical turning point can trigger abrupt climate change
Space & Earth / Earth Sciences
Apr 20, 2009 |
4.6 / 5 (58) |
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Ice ages are the greatest natural climate changes in recent geological times. Their rise and fall are caused by slight changes in the Earth's orbit around the Sun due to the influence of the other planets. But we do not know ...
Exploding asteroid theory strengthened by new evidence located in Ohio, Indiana
Space & Earth / Earth Sciences
Jul 02, 2008 |
4.5 / 5 (55) |
9
Geological evidence found in Ohio and Indiana in recent weeks is strengthening the case to attribute what happened 12,900 years ago in North America -- when the end of the last Ice Age unexpectedly turned ...
CO2 higher today than last 2.1 million years
Space & Earth / Earth Sciences
Jun 18, 2009 |
4.4 / 5 (49) |
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Researchers have reconstructed atmospheric carbon dioxide levels over the past 2.1 million years in the sharpest detail yet, shedding new light on its role in the earth's cycles of cooling and warming.
New evidence debunks 'stupid' Neanderthal myth
Other Sciences / Archaeology & Fossils
Aug 26, 2008 |
4.5 / 5 (43) |
15
Research by UK and American scientists has struck another blow to the theory that Neanderthals (Homo neanderthalensis) became extinct because they were less intelligent than our ancestors (Homo sapiens). The research ...
Ice core studies confirm accuracy of climate models
Space & Earth / Earth Sciences
Sep 11, 2008 |
3.1 / 5 (34) |
22
An analysis has been completed of the global carbon cycle and climate for a 70,000 year period in the most recent Ice Age, showing a remarkable correlation between carbon dioxide levels and surprisingly abrupt changes in ...
Long debate ended over cause, demise of ice ages -- may also help predict future
Space & Earth / Earth Sciences
Aug 06, 2009 |
4.4 / 5 (23) |
63
Researchers have largely put to rest a long debate on the underlying mechanism that has caused periodic ice ages on Earth for the past 2.5 million years - they are ultimately linked to slight shifts in solar radiation caused ...
Gullies on Mars show tantalizing signs of recent water activity
Space & Earth / Space Exploration
Mar 02, 2009 |
4.4 / 5 (19) |
15
(PhysOrg.com) -- Planetary geologists at Brown University have found a gully fan system on Mars that formed about 1.25 million years ago. The fan offers compelling evidence that it was formed by melt water ...
'Super-river' formed the English Channel
Space & Earth / Earth Sciences
Dec 02, 2009 |
4.4 / 5 (18) |
0
(PhysOrg.com) -- A team of Anglo-French scientists studying sedimentary deposits in the Bay of Biscay have concluded that Britain and France were separated by a "super-river" during three periods of glaciations, ...
Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago
Space & Earth / Earth Sciences
Nov 23, 2009 |
4.5 / 5 (17) |
3
A new study provides "incontrovertible evidence" that the volcanic super-eruption of Toba on the island of Sumatra about 73,000 years ago deforested much of central India, some 3,000 miles from the epicenter, ...
Past regional cold and warm periods linked to natural climate drivers
Space & Earth / Earth Sciences
Nov 26, 2009 |
3.8 / 5 (19) |
31
Intervals of regional warmth and cold in the past are linked to the El Niño phenomenon and the so-called "North Atlantic Oscillation" in the Northern hemisphere's jet stream, according to a team of climate scientists. These ...
Volcanoes played pivotal role in ancient ice age, mass extinction
Space & Earth / Earth Sciences
Oct 26, 2009 |
4.7 / 5 (15) |
3
(PhysOrg.com) -- Researchers here have discovered the pivotal role that volcanoes played in a deadly ice age 450 million years ago.
Sea level rise of 1 meter within 100 years
Space & Earth / Earth Sciences
Jan 08, 2009 |
2.9 / 5 (22) |
15
New research indicates that the ocean could rise in the next 100 years to a meter higher than the current sea level - which is three times higher than predictions from the UN's Intergovernmental Panel on Climate ...
Dust may settle unanswered questions on Antarctica
Space & Earth / Earth Sciences
Mar 29, 2009 |
4.8 / 5 (13) |
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Dust trapped deep in Antarctic ice sheets is helping scientists unravel details of past climate change.
Trying to spot differences in the sun
Space & Earth / Space Exploration
Jun 28, 2009 |
4.1 / 5 (14) |
11
The sun is the focus of a deepening mystery. Solar scientists want to know: Why is the sun so quiet?
Life's Ancient Island in the Ice
Space & Earth / Earth Sciences
Oct 29, 2009 |
4.6 / 5 (12) |
3
During the last ice age, massive glaciers covered much of our planet. However, a region of Alaska, Siberia and the Canadian Yukon remained ice-free. This region, known as Beringia, supported unique organisms ...
