Monthly average atmospheric carbon dioxide levels have topped 410 ppm for the first time in more than 800,000 years, according to recent research.
There’s good reason to think this will have disastrous effects on human health.
CO2 levels will dramatically increase pollution levels and related diseases, cause extreme weather events including deadly heat waves, and broaden the ranges of disease-carrying creatures like mosquitoes and ticks.
The concentration of carbon dioxide in Earth’s atmosphere hasn’t been as high as it is now since long before humans existed. Just recently, CO2 levels topped 410 ppm, according to according to observations made at the Mauna Loa Observatory in Hawaii.
There’s good reason to think this will have catastrophic effects on human health.
Carbon dioxide levels don’t necessarily have direct effects on our ability to breathe (at least, at these concentrations). But by transforming the planet, these CO2 levels will still dramatically increase pollution and related diseases, potentially slow human cognition, cause extreme weather events (including deadly heat waves), and broaden the ranges of disease-carrying creatures like mosquitoes and ticks.
Right now, CO2 levels are still climbing rapidly. They could be on track to hit 550 ppm by the end of the century, which would cause average global temperatures to rise by 6 degrees Celsius. (The goals of the Paris Agreement are to try to limit warming to less than 2 degrees C, which would help limit the severity of some of these effects – we’d still see some, but it’s considered to be the best we can do.)
Searing temperatures are already the deadliest form of extreme weather. Heat waves kill tens of thousands of people and are responsible for more deaths in the US every year than the combined effects of hurricanes, lightning, tornadoes, earthquakes, and floods.
A study published last year in the journal Nature Climate Change found that 30% of the world is already exposed to heat intense enough to kill people for 20 or more days each year. That level of intensity is defined using a heat index that takes into account temperature and humidity; above 104 degrees Farenheit (40 degrees C ), organs swell and cells start to break down.
In 2010, more than 10,000 people did in a Moscow heat wave. In 2003, some estimates say a European summer heat wave killed up to 70,000.
CO2 concentrations in the atmosphere drive temperatures up. If they aren’t brought under control and continue unchecked (we’re currently on track for at least a 3 degree C rise), some experts think that 21 out of every 100,000 deaths in the US will be caused by heat.
Higher levels of CO2 also exacerbate ozone and other pollution levels. A recent study found that air pollution kills 9 million people every year. As temperature rises, that’ll get worse.
One 2008 study found that for every degree Celsius the temperature rises because of CO2 levels, ozone pollution can be expected to kill an additional 22,000 people via respiratory illness, asthma, and emphysema.
At the same time, non-ozone air pollution linked to warmer weather will increase rates of lung cancer, allergies and asthma, and cardiovascular disease.