A worker walks through a salt pan on the eve of May Day or Labour Day on the outskirts of the southern Indian city of Chennai April 30, 2014. India is the third largest salt producing country in the world after China and U.S. with global annual production about 230 million tonnes, according to government data. (Photo by Reuters/Babu)

Lightning illuminates a thundercloud as a storm front hits the North Sea region near Westerhever, northern Germany, on August 11, 2014. (Photo by Daniel Reinhardt/AFP Photo/DPA)

“Stacked Supercell with Lightning”. This huge mesocyclone supercell was near the Nebraska / Kansas border on the night of June 22nd, 2012. What a stunning structure! (Photo and caption by Jennifer Brindley/National Geographic Traveler Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

In this January 23, 2015 photo, Guillermo Luna Martinez, 36, carries freshly painted piñatas representing Disney's Frozen snowman character Olaf downstairs to where his wife Elvia Vicente Albarran will use paper to craft the character's eyes, teeth, and distinctive tuft of hair, at the family's workshop in the Iztapalapa neighborhood of Mexico City. Though Luna and his wife have chosen to work in the family business, they plan to let their children, Guillermo, 10, and Melissa, 9, decide for themselves. “Who knows if the business will last forever”, said Luna, “I'd prefer that they study and get a career, for them to have a better future”. (Photo by Rebecca Blackwell/AP Photo)

A police officer walks along a street of the burning village of Smolenka near Chita on Monday, April 13, 2015. Russian authorities say out-of-control agricultural fires have killed at least 15 people, injured hundreds more and destroyed or damaged more than 1,000 homes in Siberia. The fires were started by farmers burning the grass in their fields, but spread quickly because of strong winds. (Photo by Evgeny Yepanchintsev/AP Photo)

Indian dancers paint their body like tigers as they perform a Tiger dance during the International day of the Tiger in Calcutta, India, July 29, 2015. Students of Calcutta are taking part in an awareness campaign aiming to draw attention to the threats that tigers face due to habitat loss and poaching. (Photo by Piyal Adhikary/EPA)

“Cub”. In the colony of penguins in South Georgia. (Photo and caption by Ondrej Zaruba/National Geographic Traveler Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

Nigerian fashion models are made up for their fashion show to promote ethnic fashion June 13, 2006 in Tel Aviv, Israel. The models said they hope to use the travelling show as a springboard to international fame, in the words of one, “to be the next Naomi Campbell”. (Photo by Uriel Sinai/Getty Images)