Ancient Cave's Clues To Chinese History

(AP)  A stalagmite rising from the floor of a cave in China is providing clues to the end of several dynasties in Chinese history.

Slowly built from the minerals in dripping water over 1,810 years, chemicals in the stone tell a tale of strong and weak cycles of the monsoon, the life-giving rains that water crops to feed millions of people.

Dry periods coincided with the demise of the Tang, Yuan and Ming dynasties, researchers report in Friday's edition of the journal Science.

In addition, the team led by Pingzhong Zhang of Lanzhou University in China noted a change in the cycles around 1960 which they said may indicate that greenhouse gases released by human activities have become the dominant influence on the monsoon.

The Wanxiang Cave is in Gansu Province, a region where 80 percent of the rainfall occurs between May and September.

Chemical concentrations in the stalagmite indicate a series of fluctuations lasting from one to several centuries and roughly similar to records of the Little Ice Age, Medieval warm period and Dark Age cold period recorded in Europe.

There were decade-long fluctuations between A.D. 190 and 530, the end of the Han Dynasty and most of the Era of Disunity, the researchers said. From 530 to 850 the monsoon declined, covering the end of the Era of Disunity, the Sui Dynasty and most of the Tang Dynasty.

The monsoon remained weak, with another sharp drop between 910 and 930, then it rose sharply over 60 years and remained strong until 1020.

The researchers found that after 1020 the monsoon varied but was generally strong until a sharp drop between 1340 and 1360: the mid 14th-century monsoon weakening. It stayed weak, with substantial fluctuation, until a sharp increase between 1850 and 1880.

According to the researchers, the 9th-century dry period contributed to the decline of the Tang Dynasty and the Mayans in Mesoamerica. It also may have contributed to the lack of unity during the Five Dynasties and Ten Kingdoms period, they said.

The following strengthening of the monsoon may have contributed to the rapid increase in rice cultivation, the dramatic increase in population, and the general stability at the beginning of the Northern Song Dynasty, they suggested, adding that the end of the Yuan and the end of the Ming are both characterized by unusually weak summer monsoons.

The research was supported by the National Science Foundations of the United States and China, the Gary Comer Science and Education Foundation, the Ministry of Science and Technology of China and the Chinese Academy of Sciences.
By AP Science Writer Randolph E. Schmid

[Keith Geddes]

There are people galore making money via grants to research `global warming` when the historians and geologists KNOW climate change has been happening since time began? LONG before mans pollution.. Top Gear featured the Bonneville Salt Flats in speed trials.. THEY were formed LONG before mans pollution.. the Earth WILL look after itself.. naturally. The Earth has never `stood still`... ha.. literally, good job.
BUT WHAT are other people putting in the air with planes? Huh? Its admitted there is weather control.
Its all kept quiet and people say.. oh what a pretty sunset when the trails are back lit by sundown. Today it hasnt stopped raining. Good for the garden.. what other *** comes down too?

[nubeginning]

Most real scientists today are skeptical about the effects of human intervention on global warming. It may have been missed by many, since the media white-washed it, but Al Gore''s Nobel price was not for science, since there was no coherent proof of his scientists'' thesis. Look it up, it is fun reading.
If you look around you today, Greenland is a desolate wasteland, however, it was arable in the 1200s, at about the time when wine was produced in England, a feat that only via modern hybridization of grapes would be feasible even today.
Should we be better stewards of our environment? No doubt. Should we clean up carbon emissions because of their adverse effects on our health? Immediately.
Will Global Warming end as soon as it started on its own? If you look at the fossil record and the recorded history of the past 10 centuries, I am sure you''d agree the answer is very likely a resounding yes.

[generey]

Cool!

[downsteamjim]

Did these early Chinese dynasties cause these early weather changes? The other option is that weather cycles have occurred for 1000''s, and millions of years. As far as greenhouse gases, Kyoto accepts the fact that greenhouse gases from China and India don''t count.

[upatree1]

Global warming is bipartisan. The affects of ignoring the health of our atmosphere has no bearing on how ignorant the right wingers are or how biligerent the left wingers are. We need people of intelligence who are willing to do research and work in a non-partisan manner putting their selfish political agenda aside and encourage the brilliant minds in this world to collectively come up with a solution. Take your opinionated political view and put it to good use; like Sarah Palin''s wardrobe and what type of puppy should be in the White House and leave it out of issues that concern every single one of us in this world mostly babies and children who have no political view but do have the right to grow up in a healthy environment.

[bpai99]

eddaly1 is a typical hate-filled conservative - make something as innocuous as archeology an indictment of those who are so stupid as not to realize conservatives are simply channeling the word of God.

Instead of trying to discredit scientific research in order to keep lining the pockets of oil companies, which not show some courage and just defend global warming? I''ve been struck at how liberals only like to focus on the negatives: rising sea levels, mass extinctions, more destructive storms, blah blah blah. What about the fact that we''re enjoying an unseasonably warm fall? Nobody gives credit to the oil companies for accelerating global warming and making beautful, warm November days possible.

[timothyone-2009]

Excavating ancient Chinese outhouses or caves...whatever...then the liberals want to tie the whole mess to green house gas? Every chance they get they try and push the lie....GLOBAL WARMING IS A SCAM GIMMICK TO STEAL MONEY FOR BOGUS LIBERAL RESEARCH.

Posted by eddaly1 at 03:49 PM : Nov 08, 2008

You right-winger are so brilliant! Filling the atmosphere with gases that trap heat has no effect on our environment? Does putting a lid on a pan of boiling water also have no effect?
Do you attack good science because you are somehow benefiting from the energy status quo, or are you just another simpleton who listens to the right-wingers because they appeal to redneck white trash with hatred for minorities? I''ll bet you also hate Obama, don''t you?
And do you feel we should have sent "them" back 100 years ago? I''d bet you do.

[eddaly1]

Excavating ancient Chinese outhouses or caves...whatever...then the liberals want to tie the whole mess to green house gas? Every chance they get they try and push the lie....GLOBAL WARMING IS A SCAM GIMMICK TO STEAL MONEY FOR BOGUS LIBERAL RESEARCH.

[Hominatrix53]

"Long ignored" by whom? Certainly not by the Chinese.

[hennighg]

Mark this: the archeology of China -- long ignored -- will change the perception of history and of the fossil record.