A tourist stands on the shore of a private beach in Naama Bay, Sharm el-Sheikh, south Sinai, Egypt, Sunday, November 8, 2015. Britain's foreign secretary says airport security in many cities will need to be overhauled if it is confirmed the Russian plane crash in the Sinai was caused by a bomb planted by the Islamic State group or someone inspired by the militants. (Photo by Vinciane Jacquet/AP Photo)

A bunker at aformer Swiss artillery fortress called Heldsberg stands near the town of St. Margareten, Switzerland March 22, 2015. Heldsberg fortress, located on the Swiss-Austrian border near the River Rhine and Lake Constance was built from 1938 to 1940 and remained in military use until 1992. Since 1993 it is open to the public as Fortress Museum Heldsberg. (Photo by Arnd Wiegmann/Reuters)

Thanks to plenty of salt minerals and heavy elements in the soil, the Dallol volcano in Ethiopia produces brilliantly colored pools of water at the top of its caldera. And, as if to add greater effect to the already stunning sights, the volcano stands apart from the salt plains around it like an island. This hotspot was created through phreatomagmatic eruptions caused by magma interacting with water, and was further altered due to the presence of salt water. (Photo by Francisco Pandolfo/Caters News)

Christian families living in a refugee camp stand under a tree in Kaga-Bandoro, Central African Republic, Tuesday February 16, 2016. Refugees in the north of Central African Republic say they hope the new president will bring peace but no one is heading home just yet. Thousands are still living in displacement camps in Kaga-Bandoro, a stronghold of the former Muslim rebel group known as Seleka that was in power for nearly a year. The one-time rebels say they are waiting to see how the election turns out before taking any action. (Photo by Jerome Delay/AP Photo)

Police officers stand near a fishing boat, the Carolina Queen III, as it rests in shallow water just off Rockaway Beach, Thursday, February 25, 2016, in the Queens borough of New York. Authorities say a Coast Guard vessel overturned while assisting the fishing boat that ran aground in an inlet off New York City. (Photo by Frank Franklin II/AP Photo)

Arab Israeli contestant Tallinn Abu Hana poses for the judges during auditions for the first Miss Trans Israel beauty pageant in Tel Aviv, Israel, Thursday, March 3, 2016. The winner will represent Israel at a Miss Trans Star International pageant to be held in Spain in August. Tel Aviv has emerged as one of the world's most gay-friendly travel destinations, standing in sharp contrast to most of the rest of the Middle East, where gays can face persecution. (Photo by Ariel Schalit/AP Photo)

A huge supercell dominates the Texas skyline like an atomic bomb explosion on April 11, 2015 in Lubbock, Texas. A huge supercell dominates the Texas skyline like an atomic bomb explosion. These incredible images were taken on April 11th, by photographer Darin Kuntz who has spent in his entire life in so-called Tornado Alley. And Darin confirmed that he snapped the storm standing in his backyard in Lubbock, Texas. (Photo by Darin Kuntz/Barcroft Media)

Developed for the British American Ambulance Corps, this new motorcycle ambulance is capable of speeding wounded soldiers 90 miles an hour from the front lines to field hospitals. Its springs are synchronized with the patient's heartbeat to avoid increasing fever when traveling over various Terrain. Viewing it in New York August 27, 1941, are left to right: constable Herbert Scott of England, driver; William E. Detlor, whose firm developed the vehicle; M. W. Stand, inspector-general of Civilian Defense, and Maj. Edward Riekert, also. (Photo by AP Photo)