It's getting warmer in Bakersfield. And Fresno, too. And not just in the summer.
Bakersfield had its second warmest year on record in 2017, the second warmest year overall, since daily weather statistics started being compiled in 1893.
But it's not just last year.
According to the National Weather Service's Hanford station, the past four years are now among the top five warmest years on record for Bakersfield. That's right, 2014, '15, '16 and '17 have all been record-setting years for overall year-round average temperatures.
Fresno has experienced a similar warming effect. The past six years are now the six warmest years on record for Bakersfield's neighbor to the north.
Brian Ochs, a weather service meteorologist in Hanford, said it's no stretch to call it climate change.
"Yes, it does appear pretty likely that's the case," Ochs said. "It's been warming across the United States and this is consistent with what we're seeing."
One symptom is higher minimum temperatures, Ochs said. On average, the overnight lows are not as low.
For example, last year Bakersfield experienced 17 days during which the low temperature remained at 80 degrees or higher. That's a record.
According to the U.S. Global Change Research Program, established by presidential initiative during the George H.W. Bush administration in 1989 and mandated by Congress in the Global Change Research Act of 1990, the fact that the Earth has warmed over the last century is unequivocal.
Multiple observations of air and ocean temperatures, sea level, and snow and ice have shown these changes to be unprecedented over decades to millennia, the program says on its website. Human influence has been the dominant cause of this observed warming.
But the effects humans see are dependent on where they live. In the West, residents experience more frequent heat waves, more persistent drought and wildfires that start earlier in the spring and last later into the fall. Other areas may see more cold waves.
But what does this warming mean for agriculture, one of Kern County's biggest economic drivers?
Blake Sanden, a farm adviser at the Kern County office of the UC Cooperative Extension, said there are two dimensions to the issue. The first is the coming 2018 growing season. The second is the long-term health and viability of valley agriculture.
"We have Kern County pistachio growers in particular who are quite concerned," Sanden said.
Several tree fruits and nuts require what are called chilling hours or chill portions.
The chilling requirement is the minimum period of cold weather after which a fruit-bearing tree will blossom. It is often expressed in chill hours, which can be calculated in different ways, all of which essentially involve adding up the total amount of time in a winter spent at certain temperatures.
The years 2014 and 2015 were examples of years when the cooling hours for pistachios were not sufficient — and the yield suffered as a result, Sanden said. Like pistachios, cherries also are very dependent on chilling portions, and cherry farming has been problematic as a result.
Almonds — Kern has the biggest production in the state — also require cold weather, but not to the extent of pistachios or cherries, according to Sanden.
Tom Frantz, who farms 40 acres of almonds near Shafter, said every farmer has noticed the recent warmer winters.
"Orchard owners are wondering how many years they have left to successfully grow almonds because the trees must go dormant for a couple months," said Frantz, who is also a clean-air activist in the valley.
"With less chilling hours, the trees don't get their rest," he said. "Insect pests can survive the winter in larger numbers. The bloom can hit earlier with the danger of frost damage on the young crop."
Said Frantz, "It is not a comforting situation to know today's young orchards may not be profitable 20 years from now."