Sacramento heat wave was made three times more likely by climate change, data show

Sacramento is feeling some excessive heat this weekend as weather officials warn of triple digit temperatures, but what’s not in the forecast is the impact of atmospheric warming from burning fossil fuels.

This particular heat wave was made three times more likely due to climate change, according researchers with Climate Central, an independent science and communications organization.

Temperatures, expected to reach 109 in Modesto, Fresno and Merced, were made four times as likely.

Climate change “has it’s nasty little fingers” on this heat wave, said Climate Central’s vice president for science Andrew Pershing.

With automated research tools used to study global temperatures, Climate Central enables anyone to search their own city and see footprints of the climate crisis on any local weather forecast.

“We look at how likely a weather event is in today’s world, and contrast that with an estimate of how likely [it] would have been in a world where humans didn’t put all this extra carbon dioxide in the atmosphere.”

Scientists have spent years studying the role of climate change versus natural weather patterns. Now a field called attribution science is beginning to answer whether human carbon emissions from burning fossil fuels has directly altering a weather event.

The tool, called the Climate Shift Index, showed that a record heat wave this week in Texas and across the southern U.S. was made five times more likely by climate change. An El Niño warming pattern is making matters worse.

Sacramento climate activists hope this type of science serves as a wake up call for local governments. Heat waves are the deadliest symptom of climate change, research shows, but California struggles to count fatalities and cities offer little beyond cooling centers.

“Climate change is a public health emergency,” said Katie McCammon, a volunteer with 350 Sacramento, a local climate advocacy group. “People have lost their lives due to climate change and we’re not willing to talk about that... We need adaptive measures.”

Extreme heat takes the heaviest toll on people without enough ways to get cool — things like working air conditioning, tree lined streets or access to swimming pools. Unhoused people and extremely low-income communities fare the worst.

That’s just one reason why Sacramento climate activists gave the city a D+ in its 2023 climate report card. The city has not offered sufficient resources to give extremely low-income and unhoused residents respite from heat waves, the report found.

In South Sacramento, Monica Negrete has a broken A/C unit that requires expensive pipe upgrades in her condo to fix. She was gifted a portable unit to keep her bedroom cool this summer, but wishes her nearby park offered more for to escape the heat.

“Why is it that our kids have to go to Elk Grove to cool down? In Elk Grove, they have water parks. Why can’t they build that out here We pay taxes,” she said. “A lot of people can’t afford to keep the A/C on 24/7. But you either get heat stroke or cool yourself down.”

This story was originally published June 30, 2023 at 11:18 AM.