A global emissions analysis by The Washington Post has found that many countries underreport their greenhouse gas emissions in their reports to the United Nations, with gaps ranging from at least 8.5 billion to a high of 13.3 billion tons a year. The investigation, which measured the difference between what countries have publicly acknowledged releasing into the air and the total emissions actually found in the atmosphere, has shown that the data the United Nations is using to build a framework to address climate change is flawed at best.

In addition to the undercounting of carbon dioxide and methane emissions, the Post found that in some cases the emissions of human-made fluorinated gases, like those used in air conditioning and refrigeration, are not reported at all. “It’s hard to imagine how policymakers are going to pursue ambitious climate actions if they’re not getting the right data from national governments on how big the problem is,” an environmental advocate told the Post. The U.N. division that collects and oversees countries’ reports and pledges attributed the gaps to “the application of different reporting formats and inconsistency in the scope and timeliness of reporting.”