The San Ysidro Port of Entry on June 24, 2021. / Photo by Carlos A. Moreno for Voice of San Diego

The hours-long waits to cross into both the U.S. and Mexico cost the region billions of dollars and thousands of jobs, an issue a binational group decided to tackle at a forum last week, reports KPBS Gustavo Solis. But solving this issue would fix another problem the story didn’t mention: air pollution. 

Vehicle traffic often sits idle for hours making the slow creep crossing from Tijuana into San Diego. A 2021 report from SANDAG shows the regional planning agency estimated that traffic emitted 1,238 kilograms of carbon dioxide per day in 2016 – that’s around 2,730 pounds. The traffic also emits nitrous oxide, which is capable of damaging lungs and likely the cause of asthma in children, according to the EPA, and other pollutants. 

Carbon dioxide naturally exists in the Earth’s atmosphere but humans are now burning fossil fuels that produce so much of it, that carbon dioxide is trapping more of the sun’s heat close to the Earth’s surface – aka, global warming. 

Another big piece of global warming news hit the Earth Monday: the amount of heat-trapping carbon dioxide in the atmosphere has shot past a key milestone – more than 50 percent higher than before humans started burning fossil fuels, known as “pre-industrial times.” It’s at a level not seen since millions of years ago when the Earth was a hothouse ocean-inundated planet, as the Associated Press put it. 

Atmospheric carbon is measured by a monitoring station at Mauna Loa in Hawaii, a method developed by Charles Keeling while at Scripps Institution of Oceanography in San Diego, and tracked by the so-named Keeling Curve. In May, carbon dioxide measured by Mauna Loa’s instruments averaged more than 420 parts per million. Data on ancient air trapped in ice cores shows carbon dioxide levels were around 270 parts per million back in 1750.

“It’s depressing that we’ve lacked the collective willpower to slow the relentless rise in CO2,” said Ralph Keeling, the son of Charles Keeling and a geochemist at Scripps, said in a press release.  “Fossil-fuel use may no longer be accelerating, but we are still racing at top speed towards a global catastrophe.”

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  1. What about the fact that there are no emission controls for cars entering the US from Mexico?

  2. Sandy –

    The people using Pemex also get to avoid CA’s crazy high gas taxes and sales taxes. Back in the Jimmy Carter years lots of people drove to TJ for gas.

    It’s a super unfair situation to San Diego taxpayers regardless of smog. I’ve argued for years for a $50.00 per head admission into the US fee to be split between Uncle Sam, CA, and SD. Mexico would start charging a fee too, which would be fair for them to do as well.

  3. Sandy –

    You are very correct.

    All cars and trucks should be smog tested before they are allowed to enter the U.S., or the driver gets to pay a juicey fine like $400.00 for a car and a couple of thousand dollars for a big truck.

    If you don’t want to pay the fine you can return to Mexico and have the vehicle tuned up there. If you decide to pay the fine and enter the U.S., you get a 30 day grace period to get your car fixed.

    A speeding ticket costs $400.00. It should be a comparable fine to spew out toxic exhaust because you bought cheap gas in Mexico.

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