Minecraft wiki entry for Biome, associated text: Biomes have a temperature value that determines if the water freezes or if it snows or rains. The required temperature values for snow and rain are less than 0.15 for snow and above 0.15 for rain. The temperature drops 0.00166666... units (1⁄600) per meter above the default sea level (Y=64), but does not change below sea level. The temperature and rainfall values of a biome are used when determining the colors of a small selection of blocks: grass, grass blocks, some leaves, vines, sugar cane. Blocks such as mossy cobblestone, mossy stone bricks, moss, dripleaves, glow berries and the stems of flowers are not affected by biome coloration[1]. The water color is affected by biome coloration but it's not based on temperature and instead is set by a color code, and the water color of each biomes varies between versions. In Java Edition most biomes have a default water color with the exception of swamps and oceans while in Bedrock Edition most biomes have unique water colors.