this is a mod, not a map ...
INSTALL:
----------
Place this folder in your minetest mods folder.
(
http://dev.minetest.net/Installing_Mods)
* After downloading, unzip the file.
* Rename the directory "minetest-mod-snow-master" to "snow"
* Copy the "snow" directory into either
../minetest/worlds/yourworld'sname/worldmods/
or
../minetest/mods/
* If you put "snow" in the ../minetest/mods/ directory, either
enable the mod from within Minetest's "Configure" button
(main menu, bottom right) or by adding this line to the
world's "world.mt" file:
load_mod_snow = true
it is designed to add snow biomes to mapgen v6, since by default it has only grass and desert.
for mapgen v5 and v7 you don't need it because they have snow by default (unless you don't have the actual version of minetest, which is 0.4.13).
since this is your first post, you are probably new.
to install mods, put them in your .minetest/mods folder. sometimes you have to rename the folder (e.g. remove the "-master" from it's name). Then you have to select the world in wich you want to play with the mod and click "configure". Select the mod and "enable" it.
also note that this mod only works on mapgenv6 worlds.
worlds created with mapgenv5 or 7 don't need this to have snow biomes.