What is the fine-grained topic of the following text: The form and development of the vertical distribution of ozone are examined during the Antarctic winter and spring by comparing profiles selected from a series of balloon‐borne ozonesonde ascents which were launched from Halley Bay in 1987. Only return the topic.
Examination of vertical distribution of ozone in Antarctic winter and spring based on ozonesonde ascents from Halley Bay in 1987.