What greenhouses do is use glass or plastic to block air from moving. They keep out the weather with a physical barrier. The glass or plastic allows light to go through but not air currents.
There is no such barrier in the atmosphere. So why use the term "greenhouse" for atmospheric effects?
Adding the term "trapping" with it emphasizes the same point. Greenhouses trap air inside using glass or plastic. There is no barrier to trap anything in the atmosphere.
The terms "greenhouse gas" and "heat trapping gas" are not analogies to anything that happens in the atmosphere. So why use such terms?
A lot of persons do not know that there is no greenhouse effect in the atmosphere. So using such terminology creates improper assumptions in their minds.
There is no excuse for misusing terminology in science. It misleads a lot of persons.
In fact, a lot of scientists are so mush-headed that the don't know there is no such thing as a greenhouse effect in the atmosphere. They, in fact, created the terminology. They were so sure that carbon dioxide heats the atmosphere that they assumed the result must be similar to a greenhouse.
You don't think scientists can be that wrong? Some of them have been claiming that nothing can heat the atmosphere but greenhouse gases. They missed the conduction, convection and evaporation that puts most heat into the atmosphere.
Scientists who miss such simple facts do not understand science. They just move words around.
A tiny amount of something can never heat a large amount of something under any set of conditions. Nothing resembling it is found anywhere in science. This is why parts per million greenhouse gasses cannot heat the atmosphere. Heat doesn't do that without nuclear reactions.
The second law of thermodynamics says heat dissipates, all the time, everywhere, without exception.
Heat cannot be trapped in the atmosphere. Large amounts of heat move into and out of the atmosphere constantly, as temperatures change 20 degrees or more between day and night.
These effects are nothing resembling what a greenhouse does.
Description of "Greenhouse Effect"Here's how the Union of Concerned Scientists described their assumptions about a greenhouse effect on their web site for several years. Recently, the statement was removed.