Tourists play at a beach covered by a thick layer of green algae on July 3, 2013 in Qingdao, China. A large quantity of non-poisonous green seaweed, enteromorpha prolifera, hit the Qingdao coast in recent days. More than 20,000 tons of such seaweed has been removed from the city's beaches. (Photo by China Foto Press)

This picture taken on July 9, 2013 shows heavy flood waters sweeping through Beichuan in southwest China´s Sichuan province. Rainstorms sweeping across parts of China have affected millions, causing landslides and disabling transportation in provinces such as Sichuan and Yunnan, state media reported. (Photo by AFP Photo)

David Rawcliffe, house and monument steward at the National Trust's Chedworth Roman Villa cleans a Roman mosiac in the new environmentally-controlled conservation shelter on March 19, 2012 near Cirencester, England. Opened this month, the multi-million pound building allows visitors to walk on suspended walkways just above the 1600-year-old Roman floors and to see recently excavated mosaics not seen for 150 years, with more to be uncovered over the coming year. (Photo by Matt Cardy/Getty Images)

Young Slovaks dressed in traditional costumes throw a bucket of water at a girl as part of Easter celebrations in the village of Trencianska Tepla, Slovakia, April 9, 2012. Slovakia's men splash women with water to symbolize youth, strength and beauty for the upcoming spring season. (Photo by Samuel Kubani/AFP)

Port staff check the damaged bridge cranes in Kaohsiung, southeast China's Taiwan on September 15, 2016. Kaohsiung Port saw facilities damage due to the effect of Typhoon Meranti. (Photo by Johnson Liu/Xinhua via ZUMA Wire)

Deacons attend a praying session during the Meskel Festival to commemorate the discovery of the true cross on which Jesus Christ was crucified on, at the Meskel Square in Ethiopia's capital Addis Ababa, September 26, 2016. (Photo by Tiksa Negeri/Reuters)

This week's full Moon as photographed from on board the International Space Station by NASA astronaut Jeff Williams on August 19, 2016. Jeff is currently Commander of the Space Station for the Expedition 48 crew. (Photo by Jeff Williams/NASA)

A gun is seen next to the body of a man was killed in a shootout with police in Manila, Philippines early October 21, 2016. According to the police, sachets containing substance believed to be drug shabu (Methamphetamine Hydrochloride) were found in the killed man's pockets. (Photo by Damir Sagolj/Reuters)