Forest cover in Orissa, which absorbs Green House Gases (GHG) generated by industrial units, may be inadequate to cope with emission levels expected to increase due to upcoming thermal power and steel plants in the state, says a noted environmental scientist.

Though the state's existing forest area has the potential to neutralise 154 million tonnes of GHG, steel, thermal power, aluminium and cement industries alone generated 164 million tonnes at present which was 7.8 per cent of the total emission of such gases in the country, M C Dash, former chairman of the State Pollution Control Board, Orissa, said.

Emission of such gases from industries, transport, agriculture and household sector had not been taken into consideration for the study due to lack of authentic data, he said delivering a lecture on "Environmental Pollution" at Siksha O Anusandhan University (SOAU) in Bhubaneswar.

Quoting data from a research conducted on the subject, Dash said when all the new thermal projects proposed to be set up in the Angul-Talcher-Jharsuguda belt with a total installed capacity of 25,860 mw were commissioned, it would generate an additional 180.2 million tonnes of GHG.

The steel projects, MoUs for which had been signed, would generate another 212 million tonnes of GHG to add to the problem, Dash said.

Dash, also a former Vice-Chancellor of Sambalpur University, suggested that all proposed thermal projects in should not be concentrated in the coal bearing belt alone as it would endanger the environment greatly.

"I would suggest that even if it would push up the cost of power generation because of the need for transporting coal, the thermal plants should be relocated to other districts to minimise the impact of environmental pollution", he said.

Of the 30 districts of Orissa, only 12 had forest cover exceeding the national target of 33 per cent (of the geographical area) for each district and 13 had less than 20 per cent forest area.

Some coastal districts like Puri, Jagatsinghpur and Bhadrak had less than five per cent forest cover. The districts of Angul, Jharsuguda, Dhenkanal, Jharsuguda, Sambalpur and Sundargarh were under severe stress because of industrial emissions, he said.

GHGs, responsible for the rise in temperature, included carbon dioxide, nitrous oxides, hydrofluorocarbons and water vapour.

The rise of carbon dioxide in the atmosphere from 280 part per million (ppm) to 387 ppm during the last 100 years had been a cause of concern and it might rise to 1200 ppm in the future which would lead to further increase in temperature.

This would result in rise in sea level submerging the coastal areas where half of the world's population lived, Dash said.

Like Environmental Protection Agency (EPA) in the USA, carbon dioxide should also be declared as a pollutant and brought under environmental regulatory provisions, he said.

Eminent environmentalist Prof Radhamohan, who also spoke, said that global warming threatened the existence of civilisation while pointing out that 2010 was the warmest year recorded for the earth so far. Cities like Moscow and New York registered temperatures of 40 degrees and 38 degrees C this summer.