`CO_2` and `H_2 O` absorbs strongly in the infrared rrgion and its presence in the atmospheere dectrases the loss fo heat form the enrth by radistiion . This global warming is called the greenhouse effect (other gases , including the oxides of nitraongen form car exhauset freons from aerosols and refrigeratirs and methane from bacteria in the soil and in the rument cows , also add to the reeenhouse effect ). The concentration fo atmospheric `CO_2` has increased by `10%` . The is rsulting in the increase in the mean temperature fo the earth by `2. 5^@ C`, varying form `2^@ C` t the equlator to `4^@ C` at the poles . This could have dramatic effects on the climate.
Instead of monitoring carbon dioxide suggest another gas that scientists could studey to substantiate the fact that ` CO_2` conentration is steadily increasing in the atmosphere ?
A. `N_2O`
B. `O_2`
C. `CH_4`
D. `O_3`