Study shows Bakken natural gas flare satellite images aren't accurate
Satellite images that circulated the Internet more than two years ago purported to show natural gas flares lighting up the Bakken Oil Patch as bright as a major metropolitan city were “highly processed,” “manipulated” and “inaccurate,” researchers at the University of North Dakota’s Energy & Environmental Research Center said Wednesday.
Chris Zygarlicke, the EERC’s deputy associate director for research, said he took an interest in the images because the science involved aligns closely with his background. He said having driven through western North Dakota and the Oil Patch, he believed the images were inaccurately portraying the area.
“There’s no way that we’re lighting up the land like you see people talking about everywhere,” he said.
So, since late 2013, Zygarlicke and researchers from the EERC and UND’s aerospace department have used images gathered from the National Oceanic and Atmospheric Administration to determine what the Oil Patch truly looks like from space.
The UND study found the images that went viral on the Internet in January 2013 and were published across worldwide media -- including in publications such as National Geographic -- were actually a representation of heat sources, not light.
It also discovered that the published images were often amplified to be 100 times brighter than the actual image.
“These images are misleading in that they give the uninformed public the idea that flares are literally lighting up many square miles of prairie countryside, creating visible light similar to large metro areas,” the study states. “So does the sky in western North Dakota light up like a million-person metropolis? A casual drive on any evening through counties of the Bakken oil play shows otherwise, so how are these satellite images being formulated?”
UND researchers stated they created improved methods for identifying, characterizing and processing gas flare images in western North Dakota to produce what Xiaodong Zhang, associate professor in the UND aerospace department, called “real gas flare images.”
Researchers developed a processing method based on data collected from the NOAA.
Zygarlicke said typical satellite sensors would capture an 800-by-800-meter area as one pixel on an image. Researchers determined typical flares only occupied one-six thousandth of a pixel. So, if a flare was present in the pixel area, the image would present the area as lit up.
Zygarlicke said the study used only nighttime images that were free of clouds and used only the middle portion of the image not affected by the Earth’s curvature.
“We were able to generate and validate the images using actual production data, which differentiate flaring emissions from other signals, including man-made light, to accurately depict nighttime satellite images of flares,” Zhang said in a release.
A side-by-side comparison of a satellite image that circulated in 2013 and an image derived from the VIRRS and day-night bands show a much darker Bakken
“That’s what it really looks like,” Zygarlicke said. “There it is, in black and white.”
The $25,000 study was funded by a UND grant program and funding from the university’s provost office.
Alison Ritter, public information officer for the North Dakota Department of Mineral Resources, said her office learned of the images in late May. The images were also presented at the North Dakota Industrial Commission meeting on Wednesday.
She said the Department of Mineral Resources, which both regulates and promotes the oil and gas industry in North Dakota, had an “uphill battle” after those images came out.
Since the UND study began, North Dakota has added rules in an attempt to decrease the amount of flaring.
“It was nice to see them come out and kind of explain what those satellite images really represented,” Ritter said. “... We all know that when you drive in western North Dakota, you can still see the stars.”