“Mother and Child”. Snow monkey at “Jigokudani hot-spring” in Nagano, Japan. (Photo by Kiyoshi Ookawa)

People take part in a snowball fight in front of the Colosseum covered by snow during a snowfall in Rome, Italy, 26 February 2018. Media reports on 26 February state that extreme cold weather is forecast to hit many parts of Europe with temperatures plummeting to a possible ten year low. (Photo by Angelo Carconi/EPA/EFE)

Visitors stand inside a church made entirely of snow and ice in southern Bavaria on January 14, 2012 in Mitterfirmiansreut, Germany. (Photo by Johannes Simon/Getty Images)

A reindeer is seen as people visit ice sculptures illuminated by coloured lights at the Harbin Ice and Snow Festival to celebrate the new year in Harbin on January 4, 2017. (Photo by Nicolas Asfouri/AFP Photo)

Students stand on the roof of a wooden boat as haze blankets the Musi River while they travel to school in Palembang, on Indonesia's Sumatra island, September 10, 2015. Indonesia is investigating 10 firms over worsening forest fires that have created a blanket of smog over Southeast Asia, threatening them with sanctions if they are found responsible, a government minister said on Tuesday. The thick haze from Indonesia's Sumatra and Kalimantan islands has forced the repeated cancellation of flights in the area and pushed air quality to unhealthy levels in neighbouring Singapore and Malaysia. (Photo by Reuters/Beawiharta)

People skate through the forest at Domaine de la Foret Perdu or the Lost Forest, a 15km weaving and zambonied forest trail made for skating in Notre-Dame-du-Mont-Carmel, near Three Rivers, Quebec January 29, 2017. (Photo by Christinne Muschi/Reuters)

The Zhangjiajie National Forest Park is a unique national forest park located in Zhangjiajie City in northern Hunan Province in the People's Republic of China. It is one of several national parks within the Wulingyuan Scenic Area.

People canoe through a flooded forest in Soomaa national park, Estonia, February 7, 2016. In this Estonian region hit by floods every spring the natural disaster is used to attract visitors and organise canoe tours through flooded territories. The floods are called Fifth Season by local people. (Photo by Ints Kalnins/Reuters)