Snow, winter storm sweep across world

Canada

People visit the Niagara Falls during extreme cold weather in Ontario, Canada, on Dec. 30, 2017. Canada experienced extreme cold weather recently. (Xinhua/Zou Zheng)

Photo taken on Dec. 30, 2017 shows the frozen channel on Lake Ontario and Toronto skyline in Toronto, Ontario, Canada. Canada experienced extreme cold weather recently. (Xinhua/Zou Zheng)