Health Wanted Show Notes: Extreme Heat—It’s Getting Hot in Here
On a global scale, June 2024 was the hottest June on record since record keeping began in 1850.
It was also the 13th month in a row where the monthly average temperature was the highest it’s been since the start of record keeping (source). It marked more than an entire year of record-breaking monthly average temperatures.
It’s been a record setting summer for heat
On July 21, 2024, Earth had the hottest day ever recorded since 1940. It was very likely the hottest day for thousands of years, based on tree ring records (source).
That record for hottest day ever lasted…until July 22nd, 2024. That’s right, we had Earth’s hottest day in thousands of years, and then the next day was hotter.
So, why is this happening? There are a few factors, but without question, the increased emission of greenhouse gases is a huge one.
Carbon dioxide, methane, ozone, nitrous oxide, chlorofluorocarbons, and water vapor are all gases that contribute to what's known as the “greenhouse effect.”
The “greenhouse effect” is called that because certain gases in our atmosphere act the same way the glass or plastic of a greenhouse would—by letting in light that becomes heat and gets trapped within the greenhouse to increase the temperature.
In the case of our planet, the sun shines on the Earth and creates energy. Some of that energy is reflected back into space, and some of it is absorbed by the Earth’s surface and radiates out as heat. Greenhouse gases in the atmosphere absorb that heat and emit it around the globe, warming the planet (source video).
The materials that make greenhouses for plants are solid. Our layer of greenhouse gases is not. Some of the heat generated should be able to filter back out into space, but the more greenhouse gases there are in our atmosphere, the less heat can escape, and the more heat stays with us to be distributed around the world.
This greenhouse effect is natural and necessary for our survival.
Without the gases, the planet would lose the heat from the sun and our global temperature would be near
We, as human beings, have made some innovations in recent history—such as burning fossil fuel to power commerce and transport, or increasing agriculture to an industrial scale—that have allowed for the exponential growth of our population, and, as a side effect, the exponential growth of greenhouse gas emissions.
One greenhouse gas, methane, is responsible for 30% of the rise in global temperature (source) and it’s estimated that livestock emissions alone account for between 11% and 17% of global greenhouse gasses (source).
Carbon dioxide is another key greenhouse gas.
It’s probably one you are most used to hearing about because it is by far the biggest contributor to global warming, and it is truly all thanks to us!
Human activity (like car travel, air travel, coal power, or pretty much anything that involves burning) has raised the level of CO2 in the atmosphere by 50% in less than 200 years.
Not only is it alarming to be at the highest-ever levels of CO2 in the atmosphere, but levels of CO2 are continuing to rise faster than they ever have before (source).
June 2023-May 2024 was an El Niño year.
El Niño is the name for a global weather pattern marked by warmer than usual ocean temperatures, which in turn cause extreme heat, floods, and droughts.
The droughts contribute to increased CO2 emissions because they disrupt the normal cycles of plant growth and decay, which disrupts plants’ ability to absorb and store CO2.
Our El Niño has ended, and we are currently in a period of neutrality. That might sound like a good thing, but it’s not really working in our favor.
El Niño heated the ocean’s temperature, and that’s what hurricanes need to form. If we were staying in an El Niño phase, that would also include wind shear, which disrupts hurricanes by changing up the speed and direction of winds.
Normally, ocean temperatures increase as summer goes on, causing hurricane season to peak around September.
Because of this season’s El Niño, ocean temperatures were already high by June. Now that the El Niño is over, those high temperatures remain, but the wind sheers are gone (source).
This combination allows stronger hurricanes to form, which we saw in late June and early July.
Hurricane Beryl was the earliest-ever category 5 hurricane to happen in a season (source).
It will be really interesting to see what happens once we switch over to a La Niña, which could happen as early as the end of summer.
La Niña seasons are the opposite of El Niño seasons and are marked by lower temperatures, so we might not see the continuation of record-breaking highs through the end of 2024.
But if temperatures do continue to climb, even in the presence of La Niña, it could be a bad sign that climate change is accelerating.
What does this mean for the human body?
In the United States, extreme heat kills more people annually than hurricanes, floods and tornadoes combined (source).
Our bodies are meant to exist at an internal temperature of 98.6 degrees. When exposed to heat for too long, our internal temperature rises and with it, which puts is at risk for many medical complications (source).
Sweating is our body’s attempt to regulate excess heat. Sweat cools the skin as it evaporates.
When there is too much heat, the body is unable to sweat enough to maintain its temperature. If it’s humid, the sweat on our skin can’t help cool us through evaporation, because there’s already too much moisture in the air.
After a while, the body becomes dehydrated. This causes the blood to thicken, forcing the heart to work harder to pump. which can lead to heart failure.
Thick blood can’t easily filter through the kidneys which means your body begins to experience a buildup of waste. Stay dehydrated for long enough and people can begin to experience kidney failure within a few hours at extreme temperatures.
Even the healthiest people, when dehydrated, can experience nausea, muscle cramps, confusion, fatigue, chest pain and irregular heartbeats.
It is possible for bodies to acclimate to heat if they are exposed regularly enough, but only up to a certain point.
Things like heatwaves, particularly in areas that aren’t used to extreme temperatures, don’t give the body enough time to adjust and therefore increase the risk of heat-related deaths.
Of course, staying hydrated and taking breaks in air conditioning are two of the top ways to beat the heat, but not everyone has access to air conditioning, and many people work in essential labor sectors that require them to be outside.
Extreme temperatures that persist through the night mean there’s no break on the body to cool down or regain fluids that were lost during the day.
Extreme heat and heatwaves are associated with pre-term births, which can have a lasting impact on infant mortality and health.
Heat and hurricanes can also contribute to illness in other ways.
Last week we talked about how disease-carrying mosquitos are thriving in these higher temperatures, and how hurricanes cause flooding that gives them new areas to breed in, increasing the prevalence of some seriously nasty diseases.
This stress on the human body can inevitably lead to stress on the healthcare system.
A recent report from the CDC found that emergency department visits for heat-related injuries in 2023 were substantially higher than in the same period from the year before (source).
This summer, dengue outbreaks have overwhelmed hospitals in South America and caused Puerto Rico to declare a public health emergency (source).
Summer of 2023 was so hot that emergency departments in Arizona saw a startling number of admissions of people with burns serious enough to require hospitalization, simply from falling on asphalt (source).
Extreme heat is also threatening people’s ability to access emergency care: rescue helicopters can’t fly in certain temperatures because the air is too thin for the blades to grab onto, forcing EMTs to delay remote rescues.
Keep in mind these are things that are happening at current temperatures, and the predictions right now are that it will get even hotter.
In 2015, The Paris Agreement was signed by 196 countries as a pledge to attempt to limit how much hotter global average temperatures can get by the end of the century.
Ideally, we’d find a way to stop and reverse temperatures before they get to 1.5 degrees higher than the average before industrialization, but we’ll settle for 2 degrees.
In case you’re unfamiliar, when we talk about “pre-industrial levels” what we mean is the average global temperature or CO2 concentration in the atmosphere from before industrialization, which would be about 1850-1900 (source).
This time period is used because it’s the first period when there are temperature records from all over the world, and in the 1900s we began burning fossil fuels at a much higher rate.
When the Paris agreement was signed nearly a decade ago, scientists predicted that we’d reach 1.5 degrees of warming by 2045. But we’ve failed to limit warming in that time, and now it appears that we’ll actually hit that benchmark in just 10 years (source).
Now this is the point in the show where I’m sure you’re feeling a bit depressed about the situation, which is unsurprising. It’s also a feeling that people who want us to remain reliant on fossil fuels are counting on.
We’re no longer in a place where anyone can reasonably deny climate change, the evidence is too strong, so the new move is to try and trick you into thinking there’s nothing to be done, that we’ve gone too far, and that’s actually not true!
The answer will come from policy and technology.
…which are two approaches we’ve already been using to address environmental issues! Don’t believe me? When’s the last time you thought about acid rain?
When you burn lots of coal, which is what a lot of modern humanity did as a source of power for many years, you also release something called sulfur dioxide into the atmosphere. This chemical then accumulates and comes back down to the earth in the form of acid rain.
In North America, this issue is now essentially gone, because we use less coal but also because we made political agreements, such as the Clean Air Act of 1970 and the Air Quality Agreement of 1991 (source).
These inspired the creation of processes and technologies for things like “desulfurization,” which removes the sulfur dioxide from emissions and keeps it out of the atmosphere (source).
Need more proof we can do it? The ozone layer acts as a shield over the earth to protect it from harmful UV rays from the sun. In 1985, it was revealed that there was a giant hole in this layer, caused by chemicals such as chlorofluorocarbons (or CFCs) that persisted in the atmosphere for decades and broke down ozone.
In 1987, the Montreal Protocol was adopted by every country, and banned the use of certain ozone-depleting chemicals, including CFCs (source).
As a result, it’s expected that the ozone layer will fully repair itself by 2050 (source).
What we need are continued large scale policy changes.
We are working towards that policy change with the Biden-Harris Administration’s implementation of both the Inflation Reduction Act and the Bipartisan Infrastructure Bill.
There’s a lot in these policies, but the highlights are outlining how to reduce U.S. greenhouse gas emissions to less than what they were in 2005 and reach 100% carbon-pollution free electricity by 2035 (source).
A big part of that is increasing solar capacity to provide 40% of all electricity in the next 6 years (source).
It sounds like a lofty goal, but 2023 was the largest year ever for new solar power installations.
Solar power and battery storage are expected to make up over 80% of new energy capacity this year.
Unlike other power sources that are finite and single-use only, batteries can not only be refilled throughout their lifetime, but can also be deconstructed and their valuable metals reused to build new batteries (source), which can help, but of course not solve, the ethical and environmental dilemmas of precious metal mining. The hope is that the need will breed creativity, and there will be greater investment in batteries that don’t rely on these metals, early versions of which already exist (source).
California, the most populous state in the union, is heeding the call with its own renewable energy goals, planning to have 60% of its energy use come from renewable sources like wind, solar, and geothermal, by 2030. It seems like they are on track to hit that goal earlier than planned (source).
This spring, for the first time, the state saw a string of days where renewable energy sources powered their entire grid for anywhere from 15 minutes to over 9 hours (source).
While we work towards systemic change, through our votes and voices, we can also impact climate and policy (to a smaller degree) through personal choice.
