New York, Jan 16 (IANS): Oil and gas production has doubled in some parts of the United States in the last two years, as researchers have seen a significant increase in the release of the lung-irritating air pollutant nitrogen dioxide and a more-than-doubling of the amount of gas flared into the atmosphere.

"We see the industry's growing impact from space, we really are at the point where we can use satellite data to give feedback to companies and regulators, and see if they are successful in regulating emissions," said study lead author Barbara Dix from University of Colorado Boulder in the US.

For the study, published in the journal Geophysical Research Letters, researchers set out to see if a suite of satellite-based instruments could help scientists understand more about nitrogen oxides pollution (including nitrogen dioxide) coming from engines in US oil and gas fields.

Combustion engines produce nitrogen oxides, which is a respiratory irritant and can lead to the formation of other types of harmful air pollutants, such as ground-level ozone, the research said.

According to the researchers, on oil and gas drilling and production sites, there may be several small and large combustion engines, drilling, compressing gas, separating liquids and gases, and moving gas and oil through pipes and storage containers.

The emissions of those engines are not controlled.

"Conventional 'inventories' meant to account for nitrogen oxides pollution from oil and gas sites are often very uncertain, underestimating or overestimating the pollutants," said study co-author Joost de Gouw.

"And there are few sustained measurements of nitrogen oxides in many of the rural areas where oil and gas development often takes place," Dix said.

So the research team turned to nitrogen dioxide data from the Ozone Monitoring Instrument (OMI) on board a NASA satellite and the Tropospheric Monitoring Instrument (TropOMI) on a European Space Agency satellite.

They also looked at gas flaring data from an instrument on the NOAA/NASA Suomi satellite system.

Between 2007 and 2019, across much of the US, nitrogen dioxide pollution levels dropped because of cleaner cars and power plants, the team found, confirming findings reported previously.

The clean air trend in satellite data was most obvious in urban areas of California, Washington and Oregon and in the eastern half of the continental US.

However, several areas stuck out with increased emissions of nitrogen dioxide: The Permian, Bakken and Eagle Ford oil and gas basins, in Texas and New Mexico, North Dakota, and Texas, respectively, the study said.