Question

What is the standard (average) ozone thickness in an area?

• A. 150 Dobson unit
• B. 200 Dobson unit
• C. 300 Dobson unit
• D. None of the above

Answer 1

Answer:

C. 300 Dobson unit

Dobson Unit (DU). 

• Ozone thickness is measured in Dobson Units (DU).
• One Dobson Unit represents a layer of ozone that is 0.01 millimeters thick under standard temperature and pressure.
• Average ozone layer thickness ranges from 300 to 500 Dobson Units.
• Thickness varies based on geographic location and time of year.
• Higher values are generally found at mid-latitudes.
• Lower values are typically found near the equator and poles.
• The Dobson unit is named after Gordon Dobson who built the first instrument to measure total ozone from the ground.