At the start of the Second World War, German forces pour into Poland from the west; the Soviet Union invade from the east; they wipe Poland off the map, leaving millions displaced.
A recent report confirmed that 2010 to 2019 was the hottest decade since record keeping began 140 years ago; in July 2018, new temperature records were set around the world.
The Polar Vortex is a low-pressure area and wide expanse of swirling cold air that is normally parked in the polar regions; in 2019, the vortex created conditions on Earth that were colder than Mars.