The Ozone Hole
Home Page Contact Site Map Ozone Hole 2006
Montreal Protocol Donate Arctic Ozone About Us
Arctic Ozone 2020 What is Ozone?

 Ozone Destruction

 Ozone Hole History
Ozone Hole 2019 Ozone Hole 2020 Ozone Hole 2021 Ozone Hole 2022
Ozone Hole 2023 Ozone Hole 2024
The Ozone Hole website is made possible by a donation from

August 2001 

NASA Earth Probe TOMS  Images

Ozone Measurement

1 Dobson Unit (DU) is defined to be 0.01 mm thickness at STP (standard temperature and pressure). Ozone layer thickness is expressed in terms of Dobson units, which measure what its physical thickness would be if compressed in the Earth's atmosphere.

The white area on the images is where data cannot be retrieved in the earth's shadow or polar night regions by the satellite.