Pebblesbysea

The Snowball theory by Paul F Hoffman and Daniel P Schrag

A potential explanation for the rare occurrence of “snowball” events in Earth history is an unusual continental configuration. Paleomagnetic evidence suggests that there were few if any continents at high latitudes 600-700 million years ago. When most continents are close to the Equator, the Earth is deprived of a mechanism that keeps the amount of carbon dioxide in the atmosphere above a critical level.

If carbon dioxide in the atmosphere were to slowly drop over millions of years due to a slow reduction in volcanic activity, global temperatures would drop and glaciers would cover the high-latitude continents, just as ice sheets cover Antarctica and Greenland today. The ice sheets prevent chemical weathering, the process that converts carbon dioxide to carbonate, from proceedin. This stabilizes the levels of carbon dioxide in the atmosphere.

But if all the continents were in the tropics, such a “safety switch” would not work, as the continents would remain ice-free even as the Earth grew colder, approaching the critical threshold for a snowball. Such a theory is speculative, although some unusual behavior of the carbon cycle is implicated by the unusually high amount of carbon-13 in sediments of Neoproterozoic time.

We may never know the true cause, as we have but simple theories for the ultimate forcing of climate change even in recent times. But clearly a successful answer must explain both why a glacial runaway happens and why it is such a rare event.

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A news article from CBC:

The land occupied by the modern state of Iraq is among the most historic on Earth. Home to humanity’s first civilization, Sumer, it has been the backdrop to thousands of years of momentous human events.

What is currently Iraq resulted from the break-up of the Ottoman Empire after World War One. When France and Britain divvied up the Middle East, Britain got the “Fertile Crescent,” the arc of land including today’s Kuwait, Iraq, Jordan, Israel and Egypt.

The borders of these nations had no roots in history but were simply agreed upon by France and Britain. Like the nations formed out of the defunct Austro-Hungarian Empire in the same period, or the crumbling of other colonial empires 40 years later, this was to cause many problems.

Initially the government of Iraq was a monarchy. Through the 1920s and 1930s, Iraq slowly gained more independence. There were many factions within the country competing for power and Iraq remained politically unstable. One thing generally agreed on, however, was dissatisfaction with the national borders that had been dictated by foreigners.

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An article from Infoworld

Microsoft Corp. has initiated 97 lawsuits throughout Europe and the Middle East during its eight-month investigation into fraudulent Web pages, with another 32 criminal complaints filed in cooperation with local authorities, the company said Wednesday.

All of the cases are against individuals who attempted to capture the log-in and password details of users by constructing fraudulent Hotmail and MSN.com sign-in pages, said Jean-Christophe Le Toquin, a Microsoft attorney. A total of 253 sites were investigated, he said.

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