Climate change was responsible for heat records being broken across the United States in February, scientists said Wednesday. In all, 16 states with a collective population of 145 million Americans experienced their hottest February since records began in 1895. Overall, the country saw its second warmest February on record.

Climate change played a primary role for it, a new analysis by scientists at World Weather Attribution, an international coalition of scientists focused on assessing possible climate change, has shown.

Read: CO2 And Climate Change: Human Activity Causes Global Warming, Science Shows EPA's Scott Pruitt Is Wrong

“We found clear and strong links between last month’s record warmth in the United States and climate change,” said Geert Jan van Oldenborgh, senior research at the Netherlands Meteorological Institute. “Temperatures like those seen across the Lower 48 this past February are becoming more and more common as cold winter months are getting rarer. The observations show a clear trend and climate models confirm it is caused by greenhouse gases.”

Temperatures last month rose 7.3 degrees Fahrenheit above the 20th century average, according to NOAA’s National Centers for Environmental Information. Only the February of 1954 was warmer in the 123-period of record. And, scientists, say, these kind of temperatures in February are set to become increasingly normal.

Already, unusually warm Februarys are three times more likely than they were when records began. And by 2050, the type of heat experienced last month could occur every three years. Overall, the U.S. is on course for its sixth warmest winter on record.

Gabriel Vecchi, professor at Princeton University Geosciences Department and Princeton Environmental Institute, said there was no doubt that carbon emissions were the driving factor.

“A full accounting of the impacts is needed, since winter months like this will become increasingly common due to past and continued carbon emission,” he said.

The analysis came just a day before the recently installed head of the Environmental Protection Agency, Scott Pruitt, said that carbon dioxide was not a primary contributor to global warming.

“No, I think that measuring with precision human activity on the climate is something very challenging to do, and there’s tremendous disagreement about the degree of impact,” he told CNBC. “So no I would not agree that it’s a primary contributor to the global warming that we see...But we don’t know that yet we need to continue the review and the analysis.”