Historic heat wave pushes California’s grid to the limit

The high temperatures are bringing increased risk of wildfire and serious public health risks.

Blazes threaten homes around California during a heat wave. (CREDIT: AP Photo/Noah Berger)
Blazes threaten homes around California during a heat wave. (CREDIT: AP Photo/Noah Berger)

What’s worse than record-breaking heat at the beginning of September? In California, the answer seems to be record-breaking heat mixed with smoke from numerous wildfires, which threaten to keep residents indoors this weekend as they attempt to escape both the high temperatures and dangerous air quality.

From San Francisco to Los Angeles, California is bracing for a weekend of potentially historic heat, with temperatures forecasted to climb as high as 115°F in some areas of the state. That heat is helping to fuel wildfires, which have broken out in the Sacramento Valley and around Los Angeles. An air pollution specialist with the state’s Air Resources Board urged people especially susceptible to health problems from smoke — the asthmatic, the elderly, or people with weakened immune systems — to remain indoors throughout Friday and Saturday.


But pushing its population indoors comes with its own set of risks for the state, which could see record-breaking levels of demand for power, as residents try to stay cool with the help of air conditioners. If too many homes and businesses demand power, it could overwhelm the grid, potentially causing a series of blackouts. In an effort to avoid that, the state has requested that Californians refrain from using major appliances between 1 p.m. and 10 p.m. on Friday.

In Los Angeles, which has seen sweltering temperatures for nearly a week, residents have already set a new record for peak electricity demand — and temperatures are only expected to climb into the weekend. Overwhelming demand worked some equipment in the city to the point of failure, leaving more than 11,000 residents without power between Wednesday night and Thursday morning.

For the past week or so, temperatures during the day have generally hovered around the high 90s and low 100s throughout much of the state. Beyond unusually high daytime temperatures, however, nighttime temperatures have also remained well-above average, falling to only the 70s or 80s. In Palm Springs, nighttime temperatures reached a low of 90 degrees on Wednesday. That leaves resident with little respite from the heat, and gives homes and businesses little time to cool off before heading into another day of soaring temperatures.

This is hardly the first record-breaking heat wave to make headlines during the summer of 2017. Earlier this month, oppressive heat throughout Eastern Europe, France, Italy, and Spain was responsible for at least six deaths and the outbreak of several wildfires. The Pacific Northwest also had to contend with extremely high heat combined with smoke from wildfires in Canada earlier this month, creating a situation similar to what is being seen now in California where high temperatures combine with wildfire to create dangerous air quality, fueling concerns about public health. And in Arizona earlier this summer, it was so hot that planes literally could not take off: at least 38 flights out of Phoenix were grounded as temperatures climbed near 120 degrees Fahrenheit.


Extreme heat is one of the signature characteristics of climate change, and abnormally warm temperatures are becoming increasingly common as climate change progresses. Since the 1980s, the occurrence of unusually hot temperatures has been rising across the globe. According to an analysis of global temperature data conducted by the New York Times, since 2005, two-thirds of temperatures are now considered “hot” and 15 percent of temperatures are considered “extremely hot.”

Heat waves and extremely hot temperatures have serious public health implications. Heat can trigger pre-existing conditions, provoking cardiovascular strain in people with heart disease, for instance, or making it difficult for people with asthma to breathe. And without taking steps to seriously curb greenhouse gas emissions, dangerous heat is only going to get worse. One study found that 30 percent of the world’s population is already exposed to deadly heat for at least 20 days per year; if carbon emissions aren’t slashed, that number could rise to as much as 50 percent by the end of the century. And a different study from earlier this summer found that extreme global warming (a global temperature increase of 7 degrees Fahrenheit) could trigger regular heat waves in Europe at would reach 131 degrees Fahrenheit.

While California braces for historic heat, the Texas Gulf Coast is still dealing with the fallout from Hurricane Harvey, which caused major, catastrophic flooding throughout the region. Like heat waves, storms like Harvey are also made more severe by climate change — offering a glimpse into the different kinds of dangers we face in a climate-changed world.