Those who oppose the president's initiatives to reduce carbon emissions appear to fit into three camps.
The first, exemplified by Sens. Marco Rubio and James Inhofe, choose not to believe what's said by the vast majority of those who know the most about climate.
The second, embodied by Exxon CEO Rex Tillerson, are those who say the climate may be changing, but the only reasonable response is to adjust to a new reality. You know: Wear lighter clothing. Drink more fluids.
The third, embodied by noted biologist Michele Bachmann and the morning team of "Fox & Friends," are those who say that carbon dioxide is not pollution, so what's the problem?
In fact, says the latter group, trees and shrubs need carbon dioxide. It's good for them. And even if the Earth is warming, warmer temperatures are good for plants, too. Right?
How wrong could people be?
To the Rubio-Inhofe group: The greenhouse effect is not a theory. It is as provable as a basic eighth-grade science assignment using plastic wrap. For something not wrapped in plastic, the uninhabitability of Venus shows one big spinning, boiling, and vaporous greenhouse effect.
To the "just get used to it" group: Tell that to the inhabitants of India and Bangladesh whose life source is the Ganges River, whose own source is Himalayan glaciers. If the depletion of the latter continues at its present pace, the glaciers will be half gone by 2100, and the Ganges will be on life support.
As for the "CO2 is good for you" group, would some basic biology actually matter? I think not. For the rest of us, however, it might:
You bet, carbon dioxide facilitates plant growth; so does heat. But an excess of either ultimately saps photosynthesis of its magic.
In Australia, studies at the Hawkesbury Institute for the Environment show that increasing CO2 causes plants to adapt (just as the Exxon CEO says we should), but not in good ways. Leaves get bigger. Evaporation accelerates. The ability to store carbohydrates drops.
In the short term, more CO2 accelerates plant growth. In the long term, it means less-healthy foliage, and ultimately less foliage, period.
What about heat? Don't plants crave it?
Yes, they do, but when things don't cool down sufficiently after dark, plants don't get a good night's sleep. They sap themselves of the energy needed for growth. The International Rice Institute blames increased temperatures in Asia for a steady decline in yields of the so-called "miracle rice," variety IR8, credited with averting an Asian famine in the 1960s.
No, excessive carbon dioxide is not a neutral presence in our atmosphere, though it is invisible, odorless, and fits into the life cycle just like sunlight and oxygen.
Of course, we shouldn't have to dip into plant biology to understand that reducing carbon pollution is good for all living things. For when we do it, we reduce other forms of pollution – ozone, hydrocarbons, mercury, sulfur dioxide, and everything else that comes with our addiction to fossil fuels -- including selective wars.
What the barkers of the status quo do is exactly what Big Tobacco did for so many years to challenge concerns about second-hand smoke. It argued "no evidence" relating it to cancer. In fact, it hardly mattered what illness we were actually talking about – asthma, emphysema, heart disease – it was all bad.
Those who resist efforts to shift to clean energy alternatives, who believe that "drill here, drill now" is the answer, don't really want to address long-range reality.
What we are doing to our planet is wrong in myriad ways. Is man responsible for climate change? Ultimately that matters less than this: Man is responsible for Earth. That is what matters.
Longtime Texas newspaperman John Young lives in Colorado. Email: jyoungcolumn@gmail.com.