Two workers shovel mud from the river as they look for gold on March 25, 2014 in Lampang, Thailand. Thai villagers from Wang Nuea, North of Thailand, look for gold in the river every year during the drought season. They are able to make an average around USD 15 per day, however two years ago they reached USD 200 in one day due to the river level dropping so much. The workers begin to search for gold at 10 AM and work until sunset, often working second jobs in the day in order to survive. (Photo by Borja Sanchez-Trillo/Getty Images)

Steam rises from Lake Superior as the ship St. Clair comes to harbor during some of the coldest temps of the year, Sunday, December 31, 2017, at Canal Park in Duluth, Minn. The St. Clair is a self-unloader built in 1976 at Sturgeon Bay, Wis., and is 770 feet long and has 26 hatches that open into 5 cargo holds, providing a load capacity of 45,000 tons. (Photo by David Joles/Star Tribune via AP Photo)

This November 8, 2019, photo provided by John Guillote shows a view from the main lab of the Sikuliaq in the Chukchi Sea. University of Washington scientists onboard the research vessel are studying the changes and how less sea ice will affect coastlines, which already are vulnerable to erosion because increased waves delivered by storms. More erosion would increase the chance of winter flooding in villages and danger to hunters in small boats. (Photo by John Guillote via AP Photo)

A gold mine worker displays gold in a local mine in Al-Ibedia locality at River Nile State, July 30, 2013. (Photo by Mohamed Nureldin Abdallah/Reuters)

In this Thursday, May 31, 2018 photo, a temporary worker using a lantern collects white asparagus from a field in Caparroso, around 85 km (52 miles) from Pamplona, northern Spain. Dubbed the “white gold” of these northern Spanish farms because of their color and the high price they fetch in markets and restaurants around the world, the stringy delicacy is planted every fall and picked each year between April and June, at the height of the spring. (Photo by Alvaro Barrientos/AP Photo)

People in Mexico wave at U.S. Border Patrol agents on horseback patrolling the U.S.-Mexico border fence near San Diego, California, U.S., November 10, 2016. (Photo by Mike Blake/Reuters)

Participants wrestle while riding yaks during Kyrgyz national horse games and festival near the Tulpar-Kul in the Chon Alai range, some 3500 metres (11483 feet) above sea level, Osh region, Kyrgyzstan, July 25, 2015. (Photo by Vladimir Pirogov/Reuters)

In this June 29, 2018 photo, a wild horse shakes off dust near a watering hole outside Salt Lake City. Harsh drought conditions in parts of the American West are pushing wild horses to the brink and forcing extreme measures to protect them. (Photo by Rick Bowmer/AP Photo)