Freeze Top Layer

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 {
 "field": "\n* <span class=\"nowrap\"><span class=\"sprite-file\" style=\"\">(link to File:BlockSprite ice.png article, displayed as 16x16px|link=Ice|alt=|class=pixel-image|)</span>(link to Ice article, displayed as <span class=\"sprite-text\">Ice</span>)</span>\n* <span class=\"nowrap\"><span class=\"sprite-file\" style=\"\">(link to File:BlockSprite snow.png article, displayed as 16x16px|link=Snow|alt=|class=pixel-image|)</span>(link to Snow article, displayed as <span class=\"sprite-text\">Snow</span>)</span>",
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A freeze top layer is a feature found throughout the Overworld.

The freeze top layer is a feature that is used to add snow and ice to mountains and cold biomes.

It attempts to generate in all chunks in the Overworld. In each chunk, it tries at each block column to generate snow or ice on the terrain surface if the biome temperature there is cold enough (below 0.15) and the block light level is less than 10. The temperature increases with the altitude, and is randomized per block up to 8 blocks using a noise.

If the upper-most block on the surface is water, an ice block replaces the water.

Snow attempts to generate on the surface if the block is supported for snow layers, e.g. not on ice or dirt path. In Java Edition, one snow layer is simply placed on the surface. Bedrock Edition uses a biome-dependent snow accumulation algorithm.

Each biome has two values for snow accumulation. The first value determines the random variation of snow layers. When 0, in most warmer biomes and a few cold, one snow layer is simply added to the surface like in Java Edition. When this value is higher, snow layers are randomized:

• A noise calculates random patches where no snow generates. Anywhere else, one layer is generated.
• When a snow layer generates horizontally bordering a full block, one layer is added for each bordering block.
• A second noise calculates random patches where multiple snow layers generate. The higher the snow accumulation value above 0.125, the larger these patches are and higher snow can accumulate.

For all snow accumulation values, see Biome § List of biome climates.

• 👁 The default snow accumulation
  
  The default snow accumulation
• 👁 Snow accumulation of 0.125: randomized, but no stacked areas
  
  Snow accumulation of 0.125: randomized, but no stacked areas
• 👁 Some colder biomes have random piles of multiple layers.
  
  Some colder biomes have random piles of multiple layers.
• 👁 The ice spikes biome has the highest snow accumulation
  
  The ice spikes biome has the highest snow accumulation

Java Edition:

Bedrock Edition: In Bedrock Edition, it is technically not a feature. The game simply iterates through each horizontal coordinate after the chunk generation to generate ice and snow.

Java Edition:

{
"type":"minecraft:freeze_top_layer",
"config":{}
}

Issues relating to "Freeze Top Layer" are maintained on the bug tracker. Issues should be reported and viewed there.