1021 GMT August 18, 2018
Palm Springs had its warmest July on record, with an average of 97.4°F. Death Valley experienced its hottest month on record, with the average temperature hitting 108.1°F. Park rangers said the heat was too much for some typically hardy birds that died in the broiling conditions, phys.org wrote.
Across California, the nighttime brought little relief, recording the highest minimum temperature statewide of any month since 1895, rising to 64.9°F.
California has been getting hotter for some time, but July was in a league of its own. The intense heat fueled fires across the state, from San Diego County to Redding, that have burned more than 1,000 homes and killed eight. It brought heat waves that overwhelmed electrical systems, leaving swaths of Los Angeles without power for days.
The extreme conditions — capping years of trends heading in this direction — have caused scientists and policymakers to speak more openly and emphatically about what is causing this dramatic shift.
A decade ago, some scientists would warn against making broad conclusions linking an extraordinary heat wave to global warming. But the pace of heat records being broken in California in recent years is leading more scientists here to assertively link climate change to unrelenting heat that is only expected to worsen as humans continue putting greenhouse gases in the air.
"In the past, it would just be kind of once in a while — the odd year where you be really warm," state climatologist Michael Anderson said.
But the last five years have been among the hottest in 124 years of record keeping, Anderson said.
"That's definitely an indication that the world is warming, and things are starting to change," said Anderson, who manages the California Department of Water Resources' state climate program.
"We're starting to see things where it's different. It's setting the narrative of climate change."
California Governor Jerry Brown, who has made climate change a central part of his agenda, was more blunt last week when discussing the devastation in Redding.
"People are doing everything they can, but nature is very powerful and we're not on the side of nature," he said.
"We're fighting nature with the amount of material we're putting in the environment, and that material traps heat."
Signs of the trend are everywhere. California endured its warmest summer on record last year. All-time temperature records have been topped in recent months — San Francisco notched 106 in September; downtown L.A. recorded its hottest Thanksgiving Day on record at 92°F.
On July 6, all-time temperature records were set at the University of California, Los Angeles (111°F), Burbank and Santa Ana (114°F), and Van Nuys (117°F). Chino hit 120°F, the highest ever recorded at an automated surface observing system in the Ontario, Riverside or Chino areas.
It was the warmest July on record in Fresno; for 26 consecutive days that month, temperatures reached or exceeded 100°F — the longest continuous stretch on record, said Brian Ochs, meteorologist with the National Weather Service in Hanford. (Maximum temperatures have continued to top 100 through the first several days of August.)
Of particular concern is how overnight temperatures continue to climb. The years with the top six warmest summertime minimum temperatures in California — defined as June through August — in descending order, are 2017, 2015, 2014, 2006, 2016 and 2013.
It's no coincidence that they're all in recent years, experts said.