Updated at 11:15 a.m. PST: This article was updated to include data and comments from Amy Townsend-Small.
A report asserting that well-maintained parks in the Irvine, Calif., area were technically polluting the environment has been amended and its official results have been re-released.
The study led by Amy Townsend-Small, an Earth system science postdoctoral researcher at the University of California at Irvine, originally reported last month that the amount of carbon emissions emitted from lawn-related maintenance was roughly four times the amount of carbon naturally collected and stored by the lawn itself.
But that is not true.
Due to an error in data in the study, the amount of emissions given off by the plethora of park maintenance has actually been found to be similar to or greater than the amount of carbon naturally collected and store by the lawn itself.
CNET was contacted Friday by the media relations department of UC Irvine and made aware of the amended study. On Tuesday, Townsend-Small offered a detailed explanation of her error in an e-mail.
The original estimate for the amount of gasoline used by landscapers per month was inadvertently multiplied by 12 twice, making that particular figure 12 times too high, and subsequently throwing off the rest of the numbers, according to Townsend-Small.
But even correcting for that egregious error, Townsend-Small found that fertilization and the type of vegetation used in parks played a large part in judging the carbon emissions.
"We also considered lawns that were fertilized at a greater rate. Because of higher energy use for fertilizer production and greater N2O emissions, the greenhouse gas emissions from these lawns are greater than the carbon sequestration potential," Townsend-Small said in her e-mail.
"Finally, we considered athletic fields that were fertilized at the same rates as the ornamental lawns. Since these turfs don't sequester carbon, the global warming potential is always positive," she said.
The rest of Townsend-Small's data, which can be found in the(also corrected to reflect the new data) is still accurate.