Environment biologists have recently reported that (i) Carbon dioxide concentration in the atmosphere has reached more than 390 ppm. (ii) The antarctic and arctic waters are becoming acidic causing thinning of animals shells. (iii) Polar ice is melting (iv) some low lying islands have submerged in sea.
(a) What are the reasons behind all these changes occurring on earth?
(b) Suggest a mechanism to control the same and if possible to reverse the trend.