Repost from SFGate

Federal scientists say 2015 on pace to be globe’s warmest

This year is on track to be the world’s hottest on record, federal scientists said Thursday, continuing a warming trend that even Pope Francis called worrisome in a remarkable 184-page papal letter.

Three of the world’s foremost weather agencies have reported the warmest start to any year since they began keeping records, and this week’s climate report by the National Oceanic and Atmospheric Administration found yet another chart-topping month for the globe.

May was a whopping 1.6 degrees above the 20th century average, the agency reported. California experienced average temperatures in May, but other places in the U.S., including Alaska and parts of the Northeast, made history for heat.

Still, California headed into June with a record temperature for the first five months of the year, 5.1 degrees above the 20th century average and 0.1 degrees warmer than the previous high, last year.

“We don’t do predictions here, but I would not be surprised if 2015 ends up the hottest year on record,” said Deke Arndt, a climate monitoring branch chief at the NOAA. “We’re almost halfway through the year and have a sizable lead on the pack.”

Last year currently stands as the planet’s warmest.

Climate scientists attribute the long-term trend of rising temperatures largely to human-caused bumps in greenhouse gases. The El Niño pattern that emerged earlier this year, though, is helping push the mercury to the extreme, they said. El Niños typically move heat from the ocean surface of the tropical Pacific into the atmosphere.

The upside of the El Niño is that it could bring rain to the West Coast, at least if it’s a strong system. Federal scientists are not only giving the El Niño a more than 80 percent chance of hanging on through winter — the rainy season in California — but saying that the event may be moderate or strong.

“This is starting to look like a typical El Niño footprint, something we didn’t see last year at this time,” said Steve Baxter, a forecaster for the NOAA’s Climate Prediction Center.

The past four years in California have seen below-average precipitation, and rain is desperately needed. The warm temperatures that have come with 2015, however, could mean less snow, which is critical in filling reservoirs.

Pope Francis, in an unorthodox move for the Catholic Church, weighed in on global warming this week. He tied fossil fuels to the problem and prompted a cool response from many Republican presidential candidates.