North Is Cold, South Is Hot

It seems quite common in fantasy worlds to have an arctic or temperate climate in the northern hemisphere, and a tropical climate in the southern hemisphere, i.e., a cold north and a hot south.

In reality, it doesn't quite works this way. You have a cold north... and a cold south. The only "hot" part is in the middle. This representation probably comes from the fact that 95% of popular fiction comes from North America, Europe and Asia... all located in the northern hemisphere, where that trope seems true.

This is Older Than Dirt: Aristotle knew the world was round, and assumed that the south pole was just as cold as the north pole, but he believed the lands near the equator were so hot that they were impassable. To be fair, his reference for "lands near the equator" was the Sahara Desert.

See also: Fantasy World Map, Patchwork Map.

Played completely straight
The northern hemisphere is cold, the southern hemisphere is hot.

Anime and Manga

 * Played straight in Dragon Ball, the north has the barren Yunzapit (Not snow, but it's quite cold) and the Muscle Tower area (THAT has the snow) and in the south there's the tropical (And aptly-named) Papaya Island where the Tenkaichi Budokai takes place.
 * Monkey D. Luffy in One Piece seems to believe this, as which direction feels warmest/coldest is how he determines north and south.

Films -- Animation

 * The Year Without a Santa Claus has Snow Miser in charge of the North and Heat Miser the South. Much of the story revolves around reconciling the two so that they can allow a Southern town to have snow for Christmas. Essentially, the Southern Hemisphere is ignored.

Mythology

 * The Ur Example is probably Norse Mythology. From The Other Wiki: "In the beginning, there were two regions: Muspellsheimr in the south, full of fire, light and heat; and Niflheimr in the north, full of arctic waters, mists, and cold." Between these two was Ginnungagap, into which the world was brought into existence.

Tabletop Games

 * Exalted does this to the entire planet - the areas around the north pole are cold tundra, while the south pole is made up of deserts, wastelands, and volcanoes.

Video Games

 * Played straight in World of Warcraft: in the south, you will find Tanaris, Stranglethorn Vale and the Swamp of Sorrows. In the north, you have Northrend
 * Although the Grim Oop North with all the Dwarves in it is... roughly equatorial. Sure, equatorial mountains are cold, but that doesn't change the fact that the middle of the world consists of frigid valleys, frigider peaks, and the Scottish—err, Twilight Highlands. (Well, and Searing Gorge.)
 * The world map of Final Fantasy II has a vast snowfield stretching on the northern part, while the southern part has two deserts and a tropical island.
 * Played straight in The Elder Scrolls series: The northern regions of Tamriel are snowy mountain ridges, while the southern coasts are tropical jungles and marshes.
 * Played straight in Nox, where you start off in the south and move upwards on the map until you reach the villainess' lair in the Grim Up North.
 * RuneScape

Western Animation

 * The Year Without a Santa Claus plays this completely straight, to the point that the earth appears to be a hemisphere that stops at the equator, with the North Pole at the top.

Played straight, but the map does not show the whole world
So the world/setting may, in fact, have a cold north and cold south.

Literature

 * In The Lord of the Rings, The southernmost land that plays a major role in the story, Haradwaith, is a hot desert, and the wastes at the northern edge of the map are the coolest.
 * The Chronicles of Narnia - temperate Narnia is north, and desert Calormen is south. Then the map stops, with no equator getting involved.
 * In The Inheritance Cycle, the southern kingdom of Surda is hot with dark-skinned inhabitants, while the north, if not cold, is more temperate. The rest of the world, however, stays unexplored.
 * In A Song of Ice and Fire, the south is warmer than the north. In the continent of Westeros, the North is freezing, while the southernmost kingdom, Dorne, is Mediterranean. The southernmost continent is described as jungly, though the known world does not extend far from its northern coast.

Live-Action TV

 * Game of Thrones, being based on the book A Song of Ice and Fire, plays this straight.

Video Game

 * Kingdom of Loathing: Seal Clubbers, barbarians who "hail from the frigid Northlands, because one character class always hails from the frigid Northlands" and who can summon seals so they can club them.

Literature

 * Averted in Dragonlance, where the bulk of the stories take place in a Southern Hemisphere continent.
 * Averted in The Stormlight Archive, where the map indicates that the continent the story takes place on is in the southern hemisphere.
 * Averted in the The Curse of Chalion and its sequels; the titular medieval-Iberia analogue is somewhere in the southern hemisphere; the Roknari, whose role in history parallels the Arabs, come from a desert archipelago to the north.

Video Games

 * Subverted by Dragon Age: Origins and Dragon Age II, which both take place in the southern hemisphere of Thedas. The fact that "frozen wastes" are located on the southern edge of the map has reportedly confused many a fantasy fan, though.
 * Averted in Civilization IV, the player can choose how the map is arranged and what temperatures go in which direction.
 * Dwarf Fortress works on the same system as Civilization IV, expect it is randomly chosen. With full maps though, there will be two cold poles and a hot equator.

Western Animation

 * Averted in Avatar: The Last Airbender, there is a north pole and a south pole. In fact, most of the first season is spent traveling from the south pole to the north.