Every sector of the global economy, from transportation to power production to manufacturing to agriculture, contributes greenhouse gases to the atmosphere, particularly carbon dioxide. Carbon dioxide, which is considered the primary greenhouse gas, is responsible for about three-quarters of emissions. It mainly comes from burning organic materials such as coal, oil, gas, wood, and solid waste.
Relentless Rise of Carbon Dioxide Levels
Scientists state that carbon dioxide levels in the atmosphere are higher than they have been at any time in the past 400,000 years. Carbon dioxide levels during ice ages were around 200 parts per million (ppm). However, they hovered around 280 ppm during the warmer interglacial periods. In 2013, carbon emissions surpassed 440 ppm for the first time in recorded history. Unfortunately, this relentless rise in CO2 will continue over the next few years.
A 2019 study conducted by researchers from Hawaii’s Mauna Loa Observatory revealed that carbon emissions have reached 415 ppm, meaning carbon dioxide was made up of 415 of every one million gas molecules in the atmosphere. According to Smithsonian Mag, the official journal published by the Smithsonian Institution in Washington, D.C., this is driven by humans' increasingly technology-driven lifestyle. Recent reports, in fact, show that global temperatures today stand at about 1.8 degrees Fahrenheit, which is higher than during the pre-industrial period.
“We keep breaking records, but what makes the current levels of CO2 in the atmosphere most troubling is that we are now well into the 'danger zone' where large tipping points in the Earth’s climate could be crossed,” Jonathan Overpeck, dean of the University of Michigan’s School for Environment and Sustainability, said.
Scientists reported that this isn’t the first time that carbon dioxide reached those levels. About 500 million years ago, CO2 was as high as 4,000 ppm during the Cambrian, while as low as 180 ppm in the more recent “ice age” on Earth. However, experts state that we should still be worried for several reasons. Our era has witnessed CO2 levels increase faster in the past century than ever before in natural history. In fact, the annual rise in carbon dioxide levels is increasing about 100 times faster than recorded during natural increases in Earth’s history.
Reports also revealed that concentrations of methane and nitrous oxide, two other greenhouse gases, have increased over the past decade. Methane emissions had a 259% increase and nitrous oxide had a 123% increase over pre-industrial levels. The continuous rise of carbon dioxide levels drives most of our global warming, threatening to drastically change the way we live in. It affects our planet’s weather and climate systems, shifting wildlife populations and habitats, rising seas, and a range of other impacts.
Higher CO2 Levels May Adversely Impact Our Cognitive Abilities
High carbon dioxide levels affect our health in many ways. Even our ability to think can be heavily affected. Researchers from the University of Colorado revealed that rising CO2 concentrations may significantly reduce our basic decision-making ability and complex strategic thinking. This could even get worse as the years pass by. The Intergovernmental Panel on Climate Change predicts outdoor CO2 levels could climb to 930 ppm by 2100.
To examine the relationship between indoor and outdoor CO2 levels and the impact on human cognition, the researchers developed a comprehensive approach that was able to predict future outdoor CO2 concentrations and the impact of localized urban emissions. According to Phys.org, an internet news portal that provides the latest news on science, the team found ut that if the outdoor CO2 concentrations do rise to 930 ppm, that would nudge the indoor concentrations to a harmful level of 1400 ppm.
"At this level, some studies have demonstrated compelling evidence for significant cognitive impairment. Though the literature contains some conflicting findings and much more research is needed, it appears that high-level cognitive domains like decision-making and planning are especially susceptible to increasing CO2 concentrations,” co-author Anna Schapiro, assistant professor of psychology at the University of Pennsylvania, said.
As CO2 builds up in poorly ventilated spaces over long periods of time, it will reduce the amount of oxygen that reaches our brains. Previous studies reveal that this can increase sleepiness and anxiety and impair cognitive function. And when CO2 concentrations reach 1400 ppm, this may cut our basic decision-making ability by 25% and complex strategic thinking by around 50%.
According to the World Economic Forum, an independent international organization committed to improving the state of the world by engaging business, political, academic, and other leaders of society to shape global, regional, and industry agendas, the findings of this study add to a growing body of research into the effect of elevated CO2 levels on brain function. A study by Harvard University, for instance, found that poorly ventilated workplaces could adversely affect employees’ cognitive performance.
Another study by the Yale School of Public Health revealed that participants exposed to polluted air suffered a significant reduction in language and mathematics test scores. The researchers found out that their language abilities were particularly affected and that men’s scores suffered more than women’s.
In 2019, scientists from the University of Colorado Boulder and the University of Pennsylvania revealed that we could find ourselves scoring 50% lower on measures of complex thought if global CO2 emissions continue to rise on their current trajectory by the end of the century. This includes the ability to plan strategies, use new information to achieve a goal, and respond to a crisis. "As we continue to increase the outdoor carbon dioxide, we're going to keep on going along here and lower our ability to solve problems. Climate change is a problem, so it's a nasty feedback [loop] in a way,” lead author Kris Karnauskas, a climate scientist, said.
Concentrated CO2 emissions might also lower the pH of blood, resulting in a number of symptoms including confusion. Fortunately, this can still change if we stop carbon concentrations at 540ppm. This means keeping global warming below two degrees Celsius. “By the end of the century, people who are trying to solve this problem of climate change, which is a complex problem, are going to be half as good at doing that. This is a hidden impact of climate change that could actually impact our ability to solve the problem itself,” Karnauskas added.