what has created at least half of the oxygen in earth's atmosphere?
In the process of photosynthesis, phytoplankton release oxygen into the water. Half of the world's oxygen is produced via phytoplankton photosynthesis. The other half is produced via photosynthesis on land by trees, shrubs, grasses, and other plants. LATEST NEWS VIDEOS.
exists and is an alternate of . Contrary to popular secular belief, tree's don't actually produce the majority of the worlds oxygen, in fact, approximately 91.6% of the worlds oxygen is produced by phytoplankton blooms in the northern hemisphere of the ocean. 3 people found this useful.