Explain The Carbon Cycle

Jeff Jacoby Pollutes Debate With Climate Fallacies

[W]hy recoil from the modest increase in carbon emissions caused by fossil-fuel use? Because more CO2 means more climate change? Happer shoots down that idea. The earth's climate is always changing, sometimes dramatically. During the medieval warming of a thousand years ago, temperatures were much higher than they are now; during the Little Ice Age six centuries later they were much lower. "Yet there is no evidence for significant increase of CO2 in the medieval warm period, nor for a significant decrease at the time of the subsequent little ice age.''

It's interesting that Jacoby asserts that "temperatures were much higher than they are now" during the medieval warm period. For their part, climate scientists say the data isn't sufficient to produce a definitive global temperature for that period. According to the National Research Council, "confidence in large-scale surface temperature reconstructions is lower before A.D. 1600 and especially before A.D. 900" due to "the relative scarcity of precisely dated proxy evidence." However, NRC noted that "presently available evidence indicates that temperatures at many, but not all, individual locations were higher during the past 25 years than during any period of comparable length since A.D. 900."

But regardless of the global temperature during the medieval warm period, Jacoby presents a fallacious argument when he seeks to refute the notion that "more CO2 means more climate change" by noting that climate change isn't always driven by CO2. That's kind of like denying that your nausea and vomiting was caused by the rotten meat you ate because the last time you had these symptoms, it was morning sickness.

No climate scientist has ever said that CO2 is the only factor influencing the climate. In fact, sorting out the myriad complex forces involved is exactly what they do. And according to of the University Corporation for Atmospheric Research, studies indicate that "warming by the sun and other variations in natural systems cannot explain" the current period of global warming.

If Jeff Jacoby wants a better discourse about climate change, I'm all for it. As a media figure with a public platform, he can start by accurately characterizing the views of those with which he disagrees, grounding arguments in sound logic, and consulting peer-reviewed science.

UPDATE: In a letter to the editor, Kerry Emanuel, a MIT atmospheric science professor and political conservative , writes that Jacoby "offers us a false choice between panic and the denial of risk.

Is carbon dioxide a pollutant? What you need to know about CO2 ...

Endangerment Finding : The Administrator finds that the current and projected concentrations of the six key well-mixed greenhouse gases … in the atmosphere threaten the public health and welfare of current and future generations.

Cause or Contribute Finding : The Administrator finds that the combined emissions of these well-mixed greenhouse gases from new motor vehicles and new motor vehicle engines contribute to the greenhouse gas pollution which threatens public health and welfare.

1. What is carbon dioxide?

Carbon dioxide is a gas, colorless, odorless and non-poisonous at low concentrations. It’s a natural chemical compound consisting of two oxygen atoms bonded to one single carbon atom. Carbon dioxide makes up 0.039% or  391 ppmv (parts per million by volume) of Earth’s atmosphere.

Carbon dioxide is plant food. Sunlight, water and carbon dioxide are absorbed by plants, algae and certain bacteria to produce organic compounds. In this way, plants extract carbon from carbon dioxide while creating oxygen as a waste product. At night, during respiration, plants emit carbon dioxide.

2. Where does carbon dioxide come from?

3. What is carbon?

Carbon is the chemical basis of all life.

It is a nonmetallic chemical element that has been known since antiquity.

Its name comes from Latin carbo, meaning coal.

writes that “Carbon is the 15th most abundant element in the Earth’s crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. It is present in all known life forms, and in the human body carbon is the second most abundant element by mass (about 18.5%) after oxygen.”

There are almost 10 million known carbon compounds in the Solar System. Carbon produces more compounds than all other chemical elements combined. Compounds made with carbon and hydrogen are called organic compounds. Almost 18% of the human body by weight consists of such organic compounds.

The global carbon cycle, integrating humans, climate, and the natural world

The carbon cycle

Global carbon cycle and climate change

Soil processes and the carbon cycle

The Global Carbon Cycle