Biomes of the World  (centered on the Americas)

  Ecological Map of the World  

[See map with currents of the world]

Biomes of the World
Biomes are classified mainly by climate and vegetation (or the lack of it).  Very seldom are ecosystems or biomes separated by a definite line.  This map is produced by interpreting "greenness" from an aerial photo composite of the world and elevation map.  There is not a globally accepted way to classify biomes or to draw their boundaries.  Do a web research and you will see a variety of different maps.