A concept illustration of the world's first forest in the sky, the Bosco Verticale green twin towers currently under construction in Milan, Italy. Towering over the city skyline the world's first forest in the sky will be a sight to behold. With tree equal to one hectare of forest spanning 27 floors these 365 and 260 foot emerald twin towers will be home to an astonishing 730 trees, 5,000 shrubs and 11,000 ground cover plants. (Photo by Boeri Studio)

A mock-up of a typical British suburban home is seen sinking into the River Thames, in a protest by Extinction Rebellion to demand faster government action on climate change in London, Britain on November 10, 2019. (Photo by Extinction Rebellion/Handout via Reuters)

Sydney artist Phillip George poses with two surfboards of his own design at Marks Park, Tamarama on December 16, 2008 in Sydney, Australia. (Photo by Don Arnold/Getty Images)

A woman walks past graffiti on a wall in the Williamsburg neighborhood of the borough of Brooklyn, in New York, September 16, 2014. The picture was taken through car window with raindrops. (Photo by Shannon Stapleton/Reuters)

Runner-up. “The City of London, looking towards the Royal Exchange and the Bank of England. The ever-changing London skyline provides many excellent opportunities for cityscape photography, none more exciting than the ebb and flow of traffic at night”. (Photo by Mark Caldon/The Guardian)

Kyrgyz dancers perform in an event gathering bedouins and nomads from around the world as part of the annual King Abdulaziz Camel Festival in Rumah desert, northeast of the Saudi capital Riyadh, on March 19, 2019. (Photo by Fayez Nureldine/AFP Photo)

Anti-government demonstrators perform in front of burning barricades as they attend a protest against a constitutional amendment, known as PEC 55, that limit public spending, in front of Brazil's National Congress in Brasilia, Brazil, November 29, 2016. (Photo by Adriano Machado/Reuters)

Visitors walk past sculptures on display as part of the Sculpture by the Sea exhibition in Sydney on October 29, 2019. Sculpture by the Sea is the world's largest annual, free-to-the-public, outdoor sculpture exhibition. (Photo by Peter Parks/AFP Photo)