SEOUL, SOUTH KOREA - MAY 19:  Prime Minister of South Korea Han Seung-Soo speaks during a opening ceremony of the C40 Large Cities Climate Summit Seoul 2009 at the Shilla Hotel on May 19, 2009 in Seoul, South Korea. Leaders of world's large cities will discuss to tackle climate changes and global warming in this four-day event. Getty Images logo Getty Images 7 months ago

SEOUL, SOUTH KOREA - MAY 19: Prime Minister of South Korea Han Seung-Soo speaks during a opening ceremony of the C40 Large Cities Climate Summit Seoul 2009 at the Shilla Hotel on May 19, 2009 in Seoul, South Korea. Leaders of world's large cities will discuss to tackle climate changes and global warming in this four-day event.