Melting glaciers, more humid air and eight other key indicators show that global warming is undeniable, scientists said on Wednesday, citing a new comprehensive review of the last decade of climate data.

Without addressing why this is happening, the researchers said there was no doubt that every decade on Earth since the 1980s has been hotter than the previous one, and that the planet has been warming for the last half-century.

This confirms the findings of the U.N. Intergovernmental Panel on Climate Change, which reported in 2007 with 90 percent certainty that climate change is occurring. The IPCC also said that human activities contribute to this phenomenon.

The new report was released after U.S. Senate Democrats delayed any possible legislation to curb climate change until September at the earliest. Prospects for U.S. climate change legislation this year are considered slim.