On Thursday, a group of climate scientists working for the U.S. government gave notice that warming temperatures in the oceans are irreversible, regardless of any drastic actions that might be taken to reduce greenhouse gas emissions.

The American Meteorological Society's climate report, which includes four independent data sets, found 2014 to be the hottest year on record, with 90 percent of the heat related to greenhouse gas emissions having been absorbed into the ocean.

In Europe alone, over 20 countries set new heat records. Africa, Asia and Australia registered near-record heat, and California's water supply hangs in the balance.

The Guardian investigated further:

"I think of it more like a fly wheel or a freight train. It takes a big push to get it going but it is moving now and will continue to move long after we continue to pushing it," Greg Johnson, an oceanographer at Noaa's Pacific Marine Environmental Laboratory, told a conference call with reporters.