Due to the Coriolis effect, the dominant ocean currents in the North Atlantic move in a circle clockwise, delivering warm water from the Caribbean Sea up to Europe, making Europe temperate instead of frozen like the same latitudes in North America.
The dominant wind patterns in the world, based on a similar force, take humid air and winds away from North Africa, forming the Sahara desert.
With the earth spinning in a different direction, the Coriolis effect would make these areas flip opposite the other side of the Atlantic ocean, settling the Sahara in the U.S. and giving most of Europe the climate of Northern Canada.
The map below created by Samuel Tammekann shows what Earth would look like if it rotated backward.
The first thing that catches your eye on this map is the North of Great Britain (Scotland), and Norway covered with snow. But the climate will become harsher not only in these two countries. If the planet rotates in the opposite direction, winters in the whole of Europe will become colder. The climate of the United States, Latin America, and China will become drier. At the same time, the climate of North Africa and Australia will become wetter.
