MiG-15 jet fighters are pictured in Kucova Air Base in Kucova, Albania on October 3, 2018. Albania retired its 224 Soviet- and Chinese-made MiGs in 2005, and since 2009 NATO neighbors Italy and Greece monitor its airspace. That led to economic decline in and around Kucova, which was called “Stalin City” during the era of Communist rule. (Photo by Florion Goga/Reuters)

Cooler temperatures begin this week as a polar vortex brings much colder conditions with the chance of snow for Snowdonia, Ogwen Valley, North Wales on 22nd October 2018. The Ogwen Valley and Tryfan Mountain looking splendid in the Autumn sunrise. (Photo by DGDImages/Alamy Live News)

A man passes at the displayed art installation “Middle way” by Romanian artist Bogdan Rata in Kiev, Ukraine, Tuesday, November 20, 2018. The monument set on the central Kiev street of Khreshchatyk, at the place of Vladimir Lenin monument which was destroyed in 2013 during the Maidan events. (Photo by Efrem Lukatsky/AP Photo)

Sukhoi Su-30SM jet fighters of the Russkiye Vityazi (Russian Knights) aerobatic team perform during a demonstration flight in Krasnoyarsk, Russia October 6, 2018. (Photo by Ilya Naymushin/Reuters)

European bisons (also known as Wisent) at the Bison farm in Muczne, southeastern Poland, 30 December 2018. The Bison farm is a continuation of bison breeding in Bieszczady, which was started in 1963. Here visitors can admire the bison of Bialowieza-Caucasian line, also called the mountain race. The European Bison is the national animal of Poland. (Photo by Darek Delmanowicz/EPA/EFE)

A tourist poses for a souvenir snap in front of autumn foliage in Pitlochry, Scotland, Britain on September 28, 2018. (Photo by Russell Cheyne/Reuters)

A hiker admires the view as Mt. Etna, Europe's largest active volcano, erupts in the background, in the Bove Valley of Etna Park, on the eastern slope of Mt. Etna, in Sicily, southern Italy, Sunday, July 4, 2021. Since Feb. 16, 2021, Mt. Etna has begun a series of eruptive episodes. (Photo by Salvatore Allegra/AP Photo)

A Bengal tigress who gave birth to four cubs at the Guadalajara Zoo, Jalisco state, Mexico runs at the zoo on October 5, 2021. (Photo by Ulises Ruiz/AFP Photo)