Climate change may be responsible for the rise and fall of Roman empire, scientists find

From the Telegraph

"Researchers who used tree growth rings to study the impact of unstable climate patterns found that they could be linked to historical events that have had devastating consequences.

Scientists discovered that periods of warm, wet weather coincided with prosperity while dry or varying conditions occurred at times of political turmoil, such as the fall of the Roman Empire and the Thirty Years' War. "

Lost Civilization may have existed beneath the Persian Gulf

From Live Science

"Veiled beneath the Persian Gulf, a once-fertile landmass may have supported some of the earliest humans outside Africa some 75,000 to 100,000 years ago, a new review of research suggests.

At its peak, the floodplain now below the Gulf would have been about the size of Great Britain, and then shrank as water began to flood the area. Then, about 8,000 years ago, the land would have been swallowed up by the Indian Ocean, the review scientist said."

WWI ships to chart past climate

From the BBC

"A new project aims to use old Royal Navy logbooks to help build a more accurate picture of how our climate has changed over the last century.

The public are being called upon to re-trace the routes taken by some 280 Royal Navy ships including historic vessels."

• Old Weather

Cave record of Britain's pioneers

When humans returned to the British Isles after the ice sheets retreated the Cheddar Gorge was one of the first places they returned to. Radiocarbon testing on bones found in Gough's Cave shows people were there 14,700 years ago. The re-occupation closely follows the warming of the climate and man could have returned to the area just a couple of years after the climate warmed.

Comet impacts may have caused ancient famine

Continuing the ancient climate change theme, scientists think multiple comet impacts 1500 years ago plunged the world into darkness and caused worldwide famines.

Historical records tell of a "global dimming" in 536CE where a fog of dust blanketed the Earth cutting daylight, dropping temperatures and causing crops to fail. Until now the cause of this dimming was unknown though some speculated it could have been due to volcanic activity. A team from Columbia University's Lamont-Doherty Earth Observatory now think it was due to multiple comet impacts. Tiny balls of condensed rock vapour found in ice cores taken at Greenland date back to 536, this is the kind of debris thrown up by a major impact. The length of time the debris was laid down indicates there was more than one impact. Two possible craters have also been identified by the team led by Dallas Abbott.

Decline of Roman and Byzantine Empires 1, 400 years ago may have been driven by climate change

A team of American and Israeli geologists have put together a much more detailed than previously possible climate record from 200 BCE to 1100 CE from geochemical analysis of a stalagmite from Soreq Cave near Jerusalem. Using an advanced ion microprobe they measured oxygen isotope signatures and impurities in the mineral layers of a stalagmite to sufficient resolution to be able to tell the rainfall for individual years and seasons. They were thus able to build up a detailed picture of the climate.

And they found the weather between 100 and 700CE became increasingly dry with "steep drops in precipitation" between 100 and 400 CE, a period that coincides with a drop in power and influence of the Roman and Byzantine Empires in the region. University of Wisconsin-Madison Professor John Valley said "Whether this is what weakened the Byzantines or not isn't known, but it is an interesting correlation."