Have you heard about the year without a summer? 1816? Scientists may have found out why the years preceding 1816 were also colder than usual. This from NPR:
"Global warming may be making some people nervous now, but from 1810 to 1819, people worried because the Earth was colder than usual.
For an entire decade, the Earth cooled almost a full degree Fahrenheit. In fact, 1816 was known as the year without a summer. And until recently, scientists weren't quite sure why everyone was shivering.
The chill of 1816 has long been blamed on an Indonesian volcano called Tambora, which erupted the year before. But no one could figure out why the years before Tambora's eruption were also colder than usual.
Now, newly uncovered evidence in the ice of Antarctica and Greenland suggests that yet another volcanic eruption may have contributed to the worldwide dip in temperatures."
