You’re not imagining it.
Southern California wasn’t always this hot, this dry, and this smoky.
Climate change is influencing many of the extreme weather events we're getting hit by, and we are responsible for climate change.
It’s important to understand that we're responsible, so we can start to make the right choices going forward, both in terms of how to adapt, and how to create a better climate future.
That’s why we’ve put together this guide about the impact of climate change on Southern California. It covers some of the basics about how far we’ve deviated from “normal” and what we can expect going forward.
One other note: climate change is scary and may seem like an insurmountable problem, but it’s not. Fatalism is easy and boring. Optimism and action are warranted and hard. What you do matters and can actually make a difference in the face of one of the biggest threats to life on planet Earth.
What’s climate change?
Quite literally, the climate around us is changing. We're seeing weather patterns and temperatures outside the norm, like extreme heat and dramatic changes in rainfall patterns, which in turn exacerbate natural disasters like wildfires.
However, the climate crisis goes far beyond the weather or a single natural disaster.
It's impacting all sorts of things:
- How Climate Change Is Fuelling the U.S. Border Crisis
- Many Of Southern California’s Beaches Could Disappear In Our Lifetime
- How Decades of Racist Housing Policy Left Neighborhoods Sweltering
- Climate Change Is A Major Threat To Stability, Spy Agencies Say
- How Climate Change Is Contributing to Skyrocketing Rates of Infectious Disease
- Wheat, one of the world’s most important crops, is being threatened by climate change
What’s driving our climate crisis?
We're driving our climate crisis by greatly increasing the amount of greenhouse gases in the atmosphere.
Those gases — including carbon dioxide — trap energy from the sun, keeping it from escaping back out into space as easily as it otherwise would. Some of that energy sticks around and heats up the atmosphere as well as the Earth. And that warming is causing all sorts of other complex changes.
We started pumping greenhouse gases into the atmosphere at astonishing rates during the Industrial Revolution and we haven’t stopped since. And now we’ve reached a point where concentrations of these gases are far beyond the narrow range they’d been in for hundreds of thousands of years, and now we're warming much faster than we were before.
The gases come from a lot of different sources, including:
- Burning fossil fuels when we travel on airplanes, ship Amazon packages around the world, and commute to and from work in our gas-burning cars.
- Burning coal and gas to power our cities.
- Drilling for gas and oil, including in L.A.
- Raising loads of livestock for food.
As of 2017, global temperatures had risen by more than 1.8 degrees Fahrenheit above what they were during pre-industrial times, A key time period that scientists look back to to see how much we've changed things by pumping gases into the atmosphere. A few degrees might not sound like a lot, but many of our ecosystems survive within a fairly narrow temperature range and humans are already feeling the impacts. And we're not adapting fast enough.
Can we turn things around?
To avoid the worst of climate change, we need to cut our greenhouse gas emissions, and the faster we do so, the better.
There's a collective global agreement to cut emissions in an effort to keep temperatures from increasing more than 3.6 degrees Fahrenheit above preindustrial levels by the end of the century. A threshold at which we'll likely already see quite scary climate impacts around the globe. We could potentially meet the goal, though it's highly dependent on how aggressively nations around the world curb their emissions.
California, for instance, will ban the sale of new gasoline-powered cars, trucks and SUVs by 2035 — one of the most aggressive policies around and an effort to dramatically cut emissions.
There are a whole range of different emissions scenarios considered when looking at how things are going to play out over the next 80 years. Under the middle of the road emissions scenarios, we could see temperatures rise around 5.4 degrees Fahrenheit, a scenario leading climate scientists indicated they feel is the most likely, per a 2021 Nature survey.
In case you’re wondering how difficult of a task we have ahead of us in terms of cutting emissions, not even the pandemic with all its shutdowns was able to make a huge dent. While everyone was celebrating clear L.A. skies during the peak of the pandemic (which mostly had to do with the weather). At the same time, CO2 concentrations in the atmosphere increased at their fifth highest rate since the National Oceanic and Atmospheric Administration started taking measurements more than 60 years ago.
By the way, oil companies have known about the link between greenhouse gases and climate change going back at least 40 years, yet actively funded misinformation campaigns to sway public opinion in favor of their products.
While eating plant-based diets and driving electric cars are a step in the right direction, large-scale systemic change is what’s needed.
Who's hit hardest?
While all communities across California feel the impacts of climate change, low income communities, people of color, immigrant communities, those with access and functional needs, and indigenous peoples, are often impacted by the worst of it.
It's been documented that lower income communities of color can experience:
- Greater urban heat island effects, directly linked to fewer green spaces and less tree coverage.
- Worse air quality because of proximity to high traffic areas, including freeways, shipping centers, oil wells, and industry, which has all sorts of deleterious effects on health.
- Greater vulnerability to wildfire smoke.
Systemic racism has resulted in some communities being harder hit by environmental problems. One of the clearest examples here in L.A., being racist housing policies that ensured that communities of color were located in areas with more industrial and business uses, exposing them to greater levels of pollution and heat.
Effects of rising heat
If you grew up in Los Angeles and don’t remember it being this miserably hot this often, that’d make sense. The hot days are getting hotter and heat waves are not only becoming more common, and more severe, but getting longer in duration. Humidity during those heat waves seems to be going up too.
How much hotter has it gotten?
- Since 1901, temperatures in California have climbed more than one degree Fahrenheit, with some locales having surpassed two degrees.
- Nine of L.A. County’s hottest years on record have occurred in the past decade.
How hot could it get?
- California could see its daily maximum average temperature rise by 5.6–8.8 degrees Fahrenheit by 2100.
- Southern California’s inland areas could see up to 5-8 degrees Fahrenheit warming by 2100 as well.
- We're going to see an increased number of extreme heat days over 95 degrees. For instance, in the year 2000, downtown L.A. experienced six extreme heat days, but by 2100, that number could balloon to 54 if the higher end estimates are correct. Over in the already hot San Fernando Valley that number could climb from 54 to 126.
- Heat waves are also projected to increase in length, with an average one in the Central Valley lasting two weeks longer by 2050.
Temperature rise will be somewhat moderated in coastal areas, which tend to benefit from the marine layer coming in to cool things down. At the same time, there’s some evidence indicating that the urban heat island effect could be working to decrease the amount of fog along the coast, especially at nighttime, which could keep things warmer.
Anyone who experienced the late summer heat wave this year knows even the coastal areas didn't get much relief.
The good news is that if we greatly curb our greenhouse gas emissions we can still lessen the number of extreme heat days we'll be subjected to.
What’s the impact of extreme heat??
High temperatures can be deadly, especially for the many Angelenos without air conditioning and those working outdoors.
Hotter and more humid nights make cooling off from brutally hot days all but impossible.
Rising temperatures can:
- Increase your risk of dying.
- Exacerbate preexisting health conditions.
- Negatively impact students’ ability to learn, particularly Black and Latino kids.
- Worsen air quality, which can greatly impact health, including that of children.
- Make it more difficult to grow crops, jeopardizing food security.
- Increase the ability of diseases to spread, and may have in part enabled the spread of yellow fever-carrying aedea aegypti mosquitos throughout California.
- Kill marine animals, desert birds, and livestock.
Hotter temperatures can also exacerbate drought and increase wildfire risk, which we get into below.
Yes, we're in a megadrought
California’s mediterranean climate naturally swings between periods of wet and dry, but climate change could make the swings more extreme. Meaning our wet periods could concentrate into shorter, more intense windows, raising the risk of flooding, while our dry periods get longer, hotter, and drier.
Currently, the West is experiencing what may be its worst megadrought in 1,200 years, with human caused climate change estimated to be responsible for some 46% of its severity.
Photos of empty reservoirs, brown lawns, and dry fields previously covered in lush green crops, have become all too familiar. But beyond agriculture and the aesthetics of your yard, drought and increased temperatures have resulted in mass tree death, appear to impede recovery of some landscapes post fire, and make it more difficult for animals like salmon in Northern California and bears in the Sierra Nevada, to survive.
Even during “normal” water years, rising temperatures dry out landscapes and plants more rapidly than they otherwise would. And those temperatures are impacting one of our most important stores of water — snow in the Sierra Nevada — which accounts for 60% of the state’s fresh water. UCLA scientists estimated that during the 2011-2015 drought, human-caused warming could have accounted for a 25% reduction in snowpack.
What this means for wildfires
All but two of California’s 20 largest wildfires on record have occurred since the year 2000, with five of the top seven occurring in 2020 alone. And it’s anticipated that large fires will continue to be a big problem.
Before we get into the role of climate change, it’s important to acknowledge that there are a bunch of other problems driving our megafires, including more than a century of wildfire suppression.
When it comes to climate change, it's kind of straightforward. Hotter temperatures cause vegetation to dry out faster than it normally would, making landscapes more susceptible to burning throughout longer periods of the year.
Mount Baldy is burning in January 💀 this is fine https://t.co/kuE0ufRnbw
— Jacob Margolis (@JacobMargolis) January 14, 2021
That hotter and drier weather also puts substantial stress on California’s trees, making them more susceptible to bark beetle attacks. During the 2012-2016 drought years, some 150 million trees died across the Sierra Nevada, potentially helping fuel some of the major fires we've seen.
Santa Ana winds — intense, dry wind events that drive destructive wildfires — could potentially decrease in severity over time. Though, if California's rainy season continues to delay, we could be left more susceptible to wind driven fires for longer as the windy season ramps up when it's still dry.
More wildfires burning throughout more of the year means more smoke exposure for the general population, more burnout amongst firefighters, and a greater risk for the communities they occur near.
Why you should worry about rising seas
Just in case you were hoping to escape the heat by heading down to the beach, that’ll get harder in the coming decades, as our beaches that are already disappearing will continue to disappear as sea levels rise.
The ocean's been encroaching on our beaches for a long time, but the rate of encroachment is increasing. Between 1900 and 1990, global sea levels rose on average by half an inch per decade, but that rate's since accelerated to 1.3 inches.
As our world has gotten hotter, so have our oceans. And as seawater increases in temperature, it expands and takes up more space. This thermal expansion accounts for roughly half of the sea level rise we’ve seen over the past century. The melting of glaciers and ice sheets also contributes.
According to the state’s sea level rise guidance, we could see as much as 6.8 feet of rise in Santa Monica. Here’s what that would look like.
Not only is the water getting closer, there are storm surges, and king tides that temporarily push water even further inland, taking more bites out of our beaches. We used to have a whole lot of marshes to help buffer the ocean, but we've destroyed most of them.
How many beaches we lose depends on a number of factors, including how much we curb emissions and how we manage erosion along our coastline.
We’ll have to decide, as sea levels rise, whether we’re going to install walls to block the waves from encroaching, or ultimately move infrastructure farther inland. The rock walls protect homes and roads, but result in a loss of beaches. We've also got to consider what to do about all the cliffs collapsing along our coast, a naturally occurring process that's threatening homes. Like wildfires, the causes and solutions of beach loss are complicated.
As a precaution, the state recommends that infrastructure along the coast be built with a 10-foot rise in mind, although some researchers think we’ve been underestimating just how bad things could get.
By the way, there are a whole bunch of other ways climate change is threatening our oceans. The majority of warming on planet Earth has occurred in our oceans over the past 50 years. Marine heat waves are becoming more common and we're seeing big die offs of sea life as a result. On top of that, Excess carbon dioxide in the atmosphere is also being absorbed and increasing ocean acidity, which, in combination with rising temperatures, is threatening crustaceans off our coast and coral reefs around the world.
Climate change is also altering ocean currents, which affects not only sea life, but weather as well.
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Mecca, California, July 2022. (Kevork Djansezian / Getty Images)
