![]() |
|
|
The above list shows replies to the following message: |
|
Msg. 54512 of 65535 |
Is this finally proof we're NOT causing global warming? The whole of the Earth heated up in medieval times without human CO2 emissions, says new study
Evidence was found in a rare mineral that records global temperatures
By Ted Thornhill Current theories of the causes and impact of global warming have been thrown into question by a new study which shows that during medieval times the whole of the planet heated up. It then cooled down naturally and there was even a 'mini ice age'. A team of scientists led by geochemist Zunli Lu from Syracuse University in New York state, has found that contrary to the ‘consensus’, the ‘Medieval Warm Period’ approximately 500 to 1,000 years ago wasn’t just confined to Europe.
In fact, it extended all the way down to Antarctica – which means that the Earth has already experience global warming without the aid of human CO2 emissions. ‘Ikaite is an icy version of limestone,’ said Lu. ‘The crystals are only stable under cold conditions and actually melt at room temperature.’
It turns out the water that holds the crystal structure together - called the hydration water - traps information about temperatures present when the crystals formed.
The scientists studied ikaite crystals from sediment cores drilled off the coast of Antarctica. The sediment layers were deposited over 2,000 years. Both climate events have been documented in Northern Europe, but studies have been inconclusive as to whether the conditions in Northern Europe extended to Antarctica. Lu’s team found that in fact, they did.
They were able to deduce this by studying the amount of heavy oxygen isotopes found in the crystals. ‘We showed that the Northern European climate events influenced climate conditions in Antarctica,’ Lu says. ‘More importantly, we are extremely happy to figure out how to get a climate signal out of this peculiar mineral. A new proxy is always welcome when studying past climate changes.’ The research was recently published online in the journal Earth And Planetary Science Letters and will appear in print on April 1. ![]() The essential American soul is hard, isolate, stoic, and a killer. It has never yet melted. ~ D.H. Lawrence |
|
|
|
|
© Webpage Design Copyright 2003-2011 http://www.atomicbobs.com/
|