Trees along Songhua River are covered in frost, Jilin City, Dec 12, 2012. [Photo/Xinhua] 

A spherical pod, named "Noah's Ark", designed by Chinese inventor Liu Qiyuan floats on a river during a test in Xianghe, Hebei province, December 12, 2012. Liu, who has spent 1.8 million yuan ($288,000) on building six "Noah's Ark"s in 8 months with the help of his former furniture factory's workers, is working on his seventh pod. The 17 cubic-metre volume vessels were built to serve as lifeboats in the event of earthquakes, tsunamis and floods. [Photo/Agencies] 

People light the candles during a memorial event marking the 75th anniversary of the Nanjing massacre at the Memorial Hall of the Victims of the Nanjing Massacre by Japanese Invaders in Nanjing, capital of East China's Jiangsu province, Dec 12, 2012. Local citizens and representatives from other countries and regions attended the activity on the eve of the 75th anniversary of the Nanjing Massacre. A total of 3,000 candles were lit up to commemorate 300,000 Chinese killed by Japanese invaders in Nanjing in 1937. [Photo/Xinhua]