News Week: This has been a year of unusual weather worldwide. In Brooklyn, residents were surprised by what seemed to be a tornado in September. That came on the heels of a 2007 tornado in the borough–the first in more than a century. Last winter, much of the northern hemisphere experienced record cold temperatures and heavy snowfalls, while the southern hemisphere had record heat. Seoul had its heaviest snowfall in recorded history; Australia, Pakistan, and Brazil experienced torrential rainfall that caused…