MCQ Detailed View

Ozone (O₃) is a molecule composed of three oxygen atoms that plays a critical role in the Earth’s stratosphere, absorbing the majority of the sun’s harmful ultraviolet (UV) radiation. Monitoring the amount of ozone in the atmosphere is essential for studying ozone depletion, climate change, and environmental health.

The quantity of ozone in the atmosphere is measured in Dobson units (DU). One Dobson unit represents the thickness, in hundredths of a millimeter, that a layer of ozone would have if it were compressed to standard temperature and pressure (STP). For example, a measurement of 300 Dobson units indicates that if all ozone in a column of the atmosphere above a given point were compressed, it would form a layer 3 millimeters thick.

The Dobson unit was named after G. M. B. Dobson, a British physicist and pioneer in ozone research. He developed the Dobson spectrophotometer, an instrument that measures the intensity of ultraviolet light and estimates ozone concentration in the atmosphere. This measurement is widely used in environmental studies and helps scientists monitor the ozone layer over time.

Other options listed are incorrect:

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  Cloning is a biological term and unrelated to ozone measurement.

  
  


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  Dalton is a unit of atomic mass.

  
  


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  Coulomb is a unit of electric charge.

  
  

Understanding Dobson units is crucial for interpreting data about ozone layer health, ultraviolet radiation exposure, and environmental protection policies. Accurate measurement of atmospheric ozone allows scientists to track ozone depletion, study the effects of pollutants such as CFCs, and take measures to protect life on Earth from increased UV radiation.

In summary, the Dobson unit is the standard unit for measuring ozone in the atmosphere, providing a clear and quantifiable way to monitor this essential component of Earth’s environment.