The chart shows monthly numbers of carbon dioxide molecules per million molecules of dry air. Because of seasonal differences, levels are higher in May than in August. Carbon dioxide acts like Earth’s thermostat: The more of it in the air, the more the planet warms. In 2023, global levels of the greenhouse gas rose to 419 parts per million, around 50 percent more than before the Industrial Revolution. That means there are roughly 50 percent more carbon dioxide molecules in the air than there were in 1750. As carbon dioxide builds up in the atmosphere, it traps heat and warms the planet. The chart shows the change in global surface temperature relative to 1951–1980, versus global carbon dioxide levels. The dotted line shows the trend line. Every additional amount of carbon dioxide in the atmosphere contributes to more warming, which is why climate scientists stress the need to get to zero emissions. Currently, carbon dioxide levels are rising at near-record rates. According to data released by the National Oceanic and Atmospheric Administration’s Global Monitoring Laboratory earlier this month, last year had the fourth-highest annual rise in global carbon dioxide levels. The chart shows the increase in global carbon dioxide levels over the course of each year. In 2023, they grew by around 2.8 parts per million. The long-term rise in carbon dioxide levels is caused by burning fossil fuels, as well as other human activities such as deforestation and concrete production. But there is also a lot of variation from year to year, which you can see in the chart above. How much carbon dioxide levels rise in a given year depends on two factors: the amount of fossil fuels burned globally, and the share of these emissions that are absorbed by the land and the ocean. Consider the first factor: While it’s true that clean energy production is rising globally, so is the demand for energy. Fossil... |