A third of Americans are already facing above-average warming

More than a third of the American population is currently experiencing rapid, above-average rates of temperature increase, with 499 counties already breaching 1.5C (2.7F) of heating, a Guardian review of climate data shows.

Hotspots of above-average warming are found across the US. Grand county in Utah, a place of sprawling deserts, cliffs and plateaus, is the second fastest warming county in the lower 48 states, while every county in New Jersey, Massachusetts and Connecticut has warmed by more than 1.5C (2.7F) since 1895.

Other locations that traditionally used to severe cold have also seen sharp temperature increases. Roseau and Kittson counties, in northern Minnesota, are both in the top five fastest warming counties in the lower 48 states, with their warming driven by winters that have heated up by around 3.8C (7F) in the state since modern record keeping began.

Globally, governments set a goal in the 2015 Paris climate agreement to avoid a temperature rise of 1.5C (2.7F) above the pre-industrial era. Beyond this point, scientists say, the world will face increasingly punishing heatwaves, storms, flooding and societal unrest.

That global threshold is in severe peril, with some forecasts warning that 1.5C (2.7F) could be breached within a decade without drastic cuts to carbon emissions. Communities will need to brace themselves for the consequences of this, according to Roop.