Question

How were ozone levels monitored in 1920?

Answer 1

Answer:

I don't know

Explanation:

Sorry.. I really don't know

..

.

Help you later

Answer 2

Answer:

It's important to continue monitoring ozone because it's so vital to life on Earth. ... The ozone layer is recovering from the effects of CFCs, but because of climate change, it will recover to different levels than its natural pre-industrial state.

The first instrument for routine monitoring of total ozone was developed by Gordon M. B. Dobson in the 1920s. The instrument, now called a Dobson spectrophotometer, measures the intensity of sunlight at two ultraviolet wavelengths: one that is strongly absorbed by ozone and one that is weakly absorbed.