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)

Bison along the Bitterroot Valley's Eastside Highway north of Stevensville, Montana, are covered in snow following a blizzard on November 23, 2010. (Photo by Perry Backus/The Missoulian)

Lindsay Heimbach goes airborne while sledding down a hill on Mt. Lemmon December 27, 2008. (Photo by James Gregg/Arizona Daily Star)

Employees of the Park Royal resort wait for a shuttle to take them to work early in the morning on April 2, 2015 in Acapulco, Mexico. Despite problems with cartel violence Semana Santa is one of the biggest tourist weeks of the year in Acapulco, a city whose entire economy depends on tourism, and officials expect around 350,000 mostly Mexican visitors this week. (Photo by Jonathan Levinson/The Washington Post)

Aerial view of contestants attending the opening ceremony of a dragon boat race on the Rongjiang River at Rong'an County on October 10, 2020 in Liuzhou, Guangxi Zhuang Autonomous Region of China. (Photo by Tan Kaixing/VCG via Getty Images)

A roadside currency exchange vendor sorts Indian currency notes at his stall in Agartala, India, December 6, 2016. (Photo by Jayanta Dey/Reuters)

A woman wades through floodwaters next to rescue workers after remnants of Typhoon Doksuri brought rains and floods in Beijing, China on August 2, 2023. (Photo by Tingshu Wang/Reuters)

Tourists view Hukou Waterfall on the Yellow River in the frigid winter on December 28, 2023 in Yan'an, Shaanxi Province of China. Freezing winter air has turned Hukou Waterfall into an icy wonderland. (Photo by VCG/VCG via Getty Images)