NASA scientists with the new satellite-based method located 39 unreported and major human-made sources to sulphur dioxide emissions which are very toxic. In an analysis of satellite data from 2005, it is found that unreported emission sources are clusters of coal burning power plants, smelters, oil and gas operations that are found in middle East and also in Mexico and other parts of Russia.From the sources, it is reported emission in the above regions in few cases two or three times which is lower than satellite-based estimates.

About 12 per cent of human-made emissions of sulphur dioxide a discrepancy that have a large impact on regional air quality said by Chris McLinden the lead author said. It is known that Sulphur dioxide a health hazard and contributor to acid rain.

“We now have an independent measurement of these emission sources that does not rely on what was known or thought known,” McLinden noted.

“When you look at a satellite picture of sulphur dioxide, you end up with it appearing as hotspots – bull’s-eyes, in effect – which makes the estimates of emissions easier,” he said.

“Quantifying the sulphur dioxide bull’s-eyes is a two-step process that would not have been possible without two innovations in working with the satellite data,” co-author NickolayKrotkov noted.

It is the first improvement in the computer processing that changes raw satellite observations from Dutch-Finnish Ozone Monitoring instrument abroad NASA`s Aura spacecraft estimates of sulphur dioxide concentrations.