A U.S. Army soldier with the 10th Special Forces Group and his military working dog jump off the ramp of a CH-47 Chinook helicopter from the 160th Special Operations Aviation Regiment during water training over the Gulf of Mexico as part of exercise Emerald Warrior 2011 on March 1, 2011. (Photo by Tech. Sgt. Manuel J. Martinez/U.S. Air Force)

Protestors affiliated with the Occupy Wall Street movement block the entrance to the Iowa Democratic Party headquarters during a protest on December 29, 2011 in Des Moines, Iowa. Thirteen people were arrested during the protest. (Photo by Andrew Burton/Getty Images)

Brad Snead walks past melting ice on the Cook Inlet beach, Saturday, March 26, 2011, in Kenai, Alaska, while looking for agates. (AP Photo/Peninsula Clarion, M. Scott Moon)

Miranda Kerr poses at the David Jones Spring/Summer fashion preview on Burke Street on August 10, 2011 in Melbourne, Australia. (Photo by Lucas Dawson)

A Peugeot 408 car is displayed during the 2011 (15th) Shenzhen-Hong Kong-Macao International Auto Show at Shenzhen Convention and Exhibition Center on June 2, 2011 in Shenzhen, Guangdong Province of China. The 6-day Auto Show will be held from June 2 to 7 with total exhibition area of 110,000 square meters. (Photo by ChinaFotoPress/Getty Images)

A Christie's auction house employee wears The Rosebury pearl and diamond tiara, bracelet and brooch on June 6, 2011 in London, England. The jewels, which formerly belonged to Hannah, Countess of Rosebury, feature in Christie's “Important Jewels” sale which take places in London on June 8, 2011. (Photo by Oli Scarff/Getty Images)

A car stands in water on Ferry Road after two magnitude 6.0 and 5.5 earthquakes struck on June 13, 2011 in Christchurch, New Zealand. The aftershocks have followed four months after the major eathquake which hit the city on February 22, 2011 resulting in the deaths of 181 people. (Photo by Martin Hunter/Getty Images)

Senior hurricane forecaster Dr. Jack Beven studies computer models as he tracks Tropical Storm Arlene at the National Hurricane Center on June 29, 2011 in Miami, Florida. Arlene is the first named storm of the 2011 Atlantic hurricane season and is moving at 8 mph, packing sustained winds of 50 mph as it heads towards the east-central coast of Mexico. (Photo by Joe Raedle/Getty Images)