Greenhouse Effect - Brief Summary

A new blog reader found my November 28 article, "What is the Greenhouse Effect?", too complicated, and thought the wavelengths chart was confusing. 

Here's a simpler explanation of the greenhouse effect, and I've added a brief explanation of the climate change hoax for new readers (the fairy tale of a coming climate catastrophe).

I've used simple numbers instead of the wavelength chart, but it might be useful to look up the word "wavelength", if you have no idea what it means.

Our planet's surface cools, especially at night, by emitting heat to the atmosphere (invisible infrared radiation, that could be seen with an infrared camera, but not your eyes).

Total outgoing infrared heat is mainly between 6.5 and 12.5 micron wavelengths (a peak centered at 9.5 microns wavelength). 

CO2 in the atmosphere absorbs a small fraction of the outgoing "heat" as Earth cools -- called the "greenhouse effect", although it has nothing to do with how real greenhouses for growing plants work.

The warming effect is mainly at night .
(see explanation at end of this article

More CO2 = more greenhouse effect ... but each doubling of the CO2 level in the air has significantly less of a greenhouse effect than the prior doubling of the CO2 level in the air (i.e.; a logarithmic effect -- see chart below).

The current CO2 level of 400 ppm can be compared to hanging four curtains over each cold window to keep a room warmer in the winter -- 500 ppm CO2 would be like hanging five curtains over each window -- maybe a little warmer than four curtains, but not much.

The CO2-absorbed infrared heat is mainly between 13 and 18 micron wavelengths (a peak is centered at 15 microns).

Total outgoing infrared heat, centered at a 9.5 micron wavelength, does not match CO2's best absorbing ability, centered at a 15 micron wavelength.

That wavelength mismatch is one reason why CO2 is a minor greenhouse gas.

The main greenhouse gas is water vapor in the air.

Water vapor absorbs most of the outgoing infrared heat (and some escapes into space too).

The strong greenhouse warming effect of water vapor in the air is slightly increased by the weak greenhouse warming effect of CO2 in the air.

No one knows exactly how much warming adding CO2 to the air will cause.

Simple lab experiments suggest a harmless +1 degree C. of warming in 200 years (assuming CO2 in the air increases +2 ppm per year for 200 years)

CO2 in the air has increased a little in the past century -- from 0.0003% to 0.0004% of the atmosphere.

Water vapor can change from 0.001% to 0.04% in just one day.

Infrared energy absorbed by CO2 in the air is "scattered" in all directions -- some "bounces" back down to Earth's surface, causing night time warming. 

Night time warming, allegedly caused by CO2, used to be called global warming.

Now global warming is called climate change.

If climate change was accurately called "night time warming", most people would want more of it (and few people could be frightened by scary "runaway warming" fairy tales told by smarmy leftists). 

CO2 in the past 4.5 billion years ranged from 175-200 parts per million, to 7,000-8,000 ppm (vs. 400 ppm today).

That means CO2 levels in the air have been up to 20x higher than today.

Yet our planet has never experienced runaway global warming from too much CO2 in the air.

In fact, ice ages began when CO2 levels were high.

As oceans cooled, from natural causes, they absorbed CO2 from the air, lowering the CO2 level in the air.

20,000 years ago northern countries like Canada were covered with ice, for at least the fifth time in 4.5 billion years.

20,000 years ago the cold oceans held a lot of dissolved CO2, causing CO2 levels in the air to be dangerously low, at 175 to 200 ppm.

"Dangerously low", because many plants used for food would not survive at less than 150 ppm CO2 in the air.

There is no explanation of how high levels of CO2 could have triggered an ice age, with Canada covered by ice, because CO2 can only cause mild warming at night.

Today's smarmy global warmunists predict CO2-caused runaway warming to scare and control people -- "do everything we say, and the catastrophe will be avoided", they falsely claim.

Their coming climate catastrophe claim is backed by absolutely no historical data, or real science!

The coming climate catastrophe is just a leftist lie, repeated again and again, with the goal of gaining more government power to tell you how to live.

Leftist politicians love more power!

And they love telling you how to live!


Why is CO2's warming effect 
mainly at night?

The layer of air just above the ground 

is known as the boundary layer.

At night this layer is very thin, just a few hundred meters thick.

During the day it grows up to a few kilometers thick. 

CO2 increases both the night time and day time temperatures. 

But at night, there is a much smaller volume of air in the boundary layer, so it is much easier to warm.

During the day, there is  a much larger volume of air in the boundary layer, so it is much harder to warm.