Global wind-shift caused Earth’s last ice age to end June 28, 2010
Posted by honestclimate in Discussions.Tags: climate change, global warming
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Global wind-shift caused Earth’s last ice age to end
DNA India
June 26, 2010
Washington, DC: A global shift in winds is what led to the end of Earth’s last ice age— an event that ushered in a warmer climate and the birth of human civilization.
It is believed that, in the geological blink of an eye, ice sheets in the northern hemisphere began to collapse and warming spread quickly to the south.
Most scientists say that the trigger, at least initially, was an orbital shift that caused more sunlight to fall across Earth’s northern half.
But they could not explain how the south dealt with the shift so fast.
And now a team of researchers looked for an answer towards a global shift in winds and proposed a chain of events that began with the melting of the large northern hemisphere ice sheets about 20,000 years ago.
The melting ice sheets reconfigured the planet’s wind belts, pushing warm air and seawater south, and pulling carbon dioxide from the deep ocean into the atmosphere, allowing the planet to heat even further.
Their hypothesis makes use of climate data preserved in cave formations, polar ice cores and deep-sea sediments to describe how Earth finally thawed out.
“This paper pulls together several recent studies to explain how warming triggered in the north moves to the south, ending an ice age,” said study co-author Bob Anderson, a geochemist at Columbia University’s Lamont-Doherty Earth Observatory.
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An Honest Climate Debate 
This is one explanation, and full glacial periods have lasted long times
and there have been interglacial periods reported before the present
one we are experiencing. Sea levels rose, precipitation patterns altered,but agriculture and animal husbandry by modern Homo sapien sapien has been possible only in the last 10,000 years because the climate allowed modified crops to be grown.
We are naturally a ‘ice planet’ and we do experience warmer periods
than today as in the Northern Hemisphere the Medieval Warm Period
between 800 – 1300 AD, and a Mini Ice Age 1300s – 1860s AD.
The Southern Hemisphere including parts of the African and sub continent and parts of Oceania and SE Asia had humans living there
in a hunter, gatherer and fisher economy. As did Southern Europe like the Neandertals or their Asian equivalent.
And certainly Australia (not New Zealand) modern humans Australian
Aborigines were present from about 60,000 years ago.
Blaming human activities on climate change is non scientific as CO2
part of 4% of Green house gases, of which 95% is water vapor, then the rest trace elements is cloud cover. Giving more precipitation to allow with warmer surface temperatures more plant growth and tree growth. Cloud cover will keep the planet warmer (depending on seasons and prevent frost forming) and cooler in summer or hotter months.
In Australia, prior to 10,000 years ago when the mainland was connected to Papua New Guinea, and Tasmania, there was less tree cover than it has today naturally, before humans started cutting down trees. So CO2 levels in the atmosphere will have increased with warmer temperatures to allow plant growth to prosper. They exudate
CO2 during the night and absorb it during the day. Those old enough to remember that in medical wards in hospitals they removed flowers and plants from wards to avoid the build up of CO2? During the night and then returned them during the day? A practice no longer used today. Frost doesn’t form at night if there is cloud cover.
Where I live at 3,500 absl in Australia, with clear days and nights
our temps plunge to minus 12 – 6 C in areas without cloud cover. Frost kills some plant life, my rhubarb has suffered, and its been there for 20 years! Until the last 2 nights.
As CO2 levels within the Greenhouse gas cycle are 99% naturally produced and 1% enhanced by human activities, I don’t see why we have to tax the air we breathe? It’s just an excuse to blame natural
cyclical events on human activities, when really we don’t control the climate. Environmental degradation of course, but when the climate plunges back again into a cooler period, don’t be holding your breath,
or cut CO2 emissions, because we need to in Australia improve naturally biological farming methodology so our soils conserve water,
and eventually moderate the numbers of people living in one area so infrastructures can cope.
Cheers Bush Bunny from Australia
BA – UNE – Archaeology and Palaeoanthropology
Cert IV – Training and Assessment in the Workplace
Cert IV – Organic agricultural production
Cert II – Animal Studies and Horticulture
Studying Diploma for Organic Agricultural Production.
The ‘global warming’ trend is not proven by any statistical methodology that is not perverted by political insistence. The entire ‘CO2’ atmospheric intensification is totally motivated by economic entities that are posed to collect billions in ‘carbon tax’ assessments that will benefit poseurs like Al Gore, Barack Obama and others who are manipulating their respective dupes. CO2 comprises 41 HUNDREDTHS of ONE PERCENT of the earth’s atmosphere, hardly an ominous threat to global stability. The most plentiful ‘gas’ in the atmosphere is water.
Yes Syd, However, water vapor is the spring of life and gallactic
subatomic particles (aka cosmic rays) when they meld with water molecules help form clouds, more clouds, more rain. Solar activity deflects some of these from the planet. When you think scientifically, GHG as in the form of clouds, does help cool the planet as well as warm it depending on what season it is. Cloud cover stops frost forming. Just look at deserts. No cloud cover, the temps are very hot during the day and cool or drop alarmingly (in their winter minus C) during the night. The alarmists always put in their graphs (on a clear day), they remove water vapor from their equations, that makes carbon dioxide look the largest GHG. When actually it only makes up 4% of GHG, and over 3% is naturally formed.
I agree the basis of green technology and carbon credits is promoted by banks and investors (like Tim Flannery and Gore) and others seeing $$’s to be made have been willful participants in one of the biggest frauds of the 21st Century. Talk about the 18th Century South Sea Bubble, this is much more damaging, the 21st
Carbon bubble. But before that bubble bursts, maybe innocent investors can get their money out of these bogus schemes.