Peter Clack in his Nov 12 post said “The ability of carbon dioxide to warm the atmosphere drops sharply at 20 parts per million. By 100ppm its effect is almost nothing.”
The job of keeping the air warm & moist, the post said, is done almost entirely by water vapour (95%), and added that “this is ignored in the UN global warming/climate change hoax.”
The ability of carbon dioxide to warm the atmosphere drops sharply at 20 parts per million. By 100ppm its effect is almost nothing. The job of keeping the air warm & moist is done almost entirely by water vapour (95%). This is ignored in the UN global warming/climate change hoax. pic.twitter.com/PhHjDW9kTW
— Peter Clack (@PeterDClack) November 12, 2022
The claim is accompanied by two images titled ‘CO2 can’t cause dangerous Warming’ and ‘The World of CO2 produced in 2008 and 2006 respectively.
As of Nov 17, 2022, the claim has been liked 5,266 times, retweeted 2618 times, and has received 130 replies. The tweep also has almost 70,000 followers and follows about 37,500 other Twitter users.
The University Corporation for Atmospheric Research (UCAR) describes Carbon dioxide as an important greenhouse gas that helps to trap heat in our atmosphere. Without it, our planet would be inhospitably cold.
It however said that “an increase in CO2 concentrations in our atmosphere is causing average global temperatures to rise, disrupting other aspects of Earth’s climate.”
To explain how Carbon dioxide traps heat, the Columbia Climate School breaks it down that “when sunlight reaches Earth, the surface absorbs some of the light’s energy and reradiates it as infrared waves, which we feel as heat. These infrared waves travel up into the atmosphere and will escape back into space if unimpeded.
“Oxygen and nitrogen don’t interfere with infrared waves in the atmosphere. That’s because molecules are picky about the range of wavelengths that they interact with.”
It however noted that “with CO2 and other greenhouse gases, it’s different. Carbon dioxide, for example, absorbs energy at a variety of wavelengths between 2,000 and 15,000 nanometers — a range that overlaps with that of infrared energy. As CO2 soaks up this infrared energy, it vibrates and re-emits the infrared energy back in all directions. About half of that energy goes out into space, and about half of it returns to Earth as heat, contributing to the greenhouse effect.”
Buttressing this, the National Aeronautics and Space Administration (NASA) says Carbon dioxide in the atmosphere warms the planet, causing climate change. Human activities have raised the atmosphere’s carbon dioxide content by 50% in less than 200 years.
Atmospheric Carbon Dioxide (parts per million)
Atmospheric carbon dioxide, according to the U.S. Geological Survey comes from two primary sources; natural and human activities. Natural sources of carbon dioxide include most animals, which exhale carbon dioxide as a waste product. Human activities that lead to carbon dioxide emissions come primarily from energy production, including burning coal, oil, or natural gas.
Although nature tends to balance-out natural sources of carbon dioxide through the carbon cycle and carbon sinks, human sources of outdoor carbon dioxide disrupted this delicate balance. Common anthropogenic sources of atmospheric carbon dioxide include; Industrial processes, like refineries, chemical production, and cement; Electricity production, especially coal-fired power plants; Transportation, like cars, trucks, and planes.
Meanwhile, the global average carbon dioxide set a new record high in 2021: 414.72 parts per million. Parts per million (PPM) is a unit of measurement used when expressing a very dilute concentration level of pollutants in the air, water, and other fluids.
NASA says “the concentration of carbon dioxide in Earth’s atmosphere is currently at nearly 412 parts per million (ppm) and rising. This represents a 47 percent increase since the beginning of the Industrial Age, when the concentration was near 280 ppm, and an 11 percent increase since 2000, when it was near 370 ppm.
The claim that “The ability of carbon dioxide to warm the atmosphere drops sharply at 20 parts per million. By 100ppm its effect is almost nothing. The job of keeping the air warm & moist is done almost entirely by water vapour” is FALSE.
Carbon dioxide is the fourth most abundant component of dry air. Today it has a concentration of over 400 ppm in the atmosphere. Before the industrial activity, there was around 270 ppm in the atmosphere. Carbon dioxide levels in the atmosphere have thus risen about 40% since the start of the Industrial Revolution, which is raising global temperature.
The ability of CO2 to warm the atmosphere does not drop, the atmosphere becomes warmer as CO2 levels increase.