The landmark climate deal signed by 175 countries last month calls for the "verification and certification" of greenhouse gases, but a key question remains: how will the global community ensure that nations are hitting their emission targets?

One solution is a global satellite system that would track and monitor emissions on a nation-by-nation basis – with an ability even to get data down to the square mile.

Scientists at the Paris-based Centre National d'Études Spatiales, or CNES, France's space agency, unveiled plans this week.

"It's a new step in the monitoring of climate change," Jean-Yves Le Gall, president of CNES, told Take Two. "The different countries will know exactly who will be the polluters...and inside the country you will know exactly where are these emissions."

The system, which would include satellites from multiple countries, would also add an important layer of accountability, said Ben Orlove, director for the Center for Research on Environmental Decisions, at Columbia University.

"These multiple systems will keep tabs on each other," said Orlove. "There's really going to be no place for a polluter to hide."

If the proposal moves forward, the satellites could start collecting data as early as 2020, according to CNES in Paris.