By Agence France-Presse
NASA's Carbon Monitoring System (CMS) tracked sources and sinks for carbon and made high-resolution models of the planet's flows of carbon, said the report.
"Now, President Donald Trump's administration has quietly killed the CMS," it said, describing the move as the latest in a "broad attack on climate science," mounted by the White House.
NASA did not immediately respond to a request for comment from AFP.
The journal Science said NASA "declined to provide a reason for the cancellation beyond 'budget constraints and higher priorities within the science budget.'"
It also quoted US space agency spokesman Steve Cole as saying there was no mention of the CMS in a budget deal signed in March, which "allowed the administration's move to take effect."
Existing grants would be allowed to finish but no new research would be supported, the report said.
Trump has already canceled another earth science mission, the Orbiting Carbon Observatory 3 (OCO-3), and announced the US pullout of the 2015 Paris climate accord.
According to Kelly Sims Gallagher, director of Tufts University's Center for International Environment and Resource Policy in Medford, Massachusetts, the CMS cuts jeopardize efforts to verify the national emission cuts agreed to in the Paris climate deal.
"If you cannot measure emissions reductions, you cannot be confident that countries are adhering to the agreement," she told the magazine.
Canceling the CMS "is a grave mistake."