Is there any reason to be skeptical of the greenhouse effect itself?

Personally, I don't think there is.  Evidence for it is out there for everyone to see.

Ever notice that cloudy winter nights stay warmer than clear ones?  That's because of downward IR radiation from the clouds, which tend to be warmer than the clear sky.

Ever notice how summer nights tend to cool down much slower than winter nights?  Thank the greater amount of water vapor in the atmosphere, radiating more power downward at you.

If you want to explore this further, you can get yourself an IR thermometer and point it at the sky.  You'll find that it varies a lot, depending on the weather and whether the sky is clear or cloudy. The thermometer is responding to the downward radiation from the atmosphere, and since water vapor is the most abundant greenhouse gas (and is variable in amount) you can even use the temperature that you read on clear days to estimate the integrated water vapor in the sky above you (what's called "precipitable water"). There's a nice article in the Bulletin of the American Meteorological Society by the electronics genius Forrest Mims about how to do that. Reference given in the comments.

Theory based on the properties of CO2 suggested that, at the current rate we pump it into the atmosphere, we should expect a 0.2 Watts per square metre per decade increase in radiative forcing.

When we measured the greenhouse impact of CO2 over a decade at two different locations in the US, the experimentally observed increase in radiative forcing was 0.2 Watts per square metre per decade.

In other words ... theory predicted the greenhouse effect and the impact CO2 has. Then we measured it experimentally and found the theory was spot on. 

Arguing the greenhouse effect is wrong or dodgy science is like arguing the world is flat ... these people are cranks and should only be allowed plastic spoons.

The proof is outside your window - global warming/climate change is here now and it'll stay with us for quite awhile. So all ya gotta do is pull your head out of your *** and take a look at what's happening across the globe....

Darwin here is some history that I submitted to a question recently, that debunks the theory at its source.

https://answers.yahoo.com/question/index?qid=20200...

The GHE theory is a thought experiment, unable to be proven experimentally and is a farce.

Any diagram depicting this farce shows a blueprint for a perpetual motion engine that violates the first and second laws of thermodynamics. CO2 does not trap "heat" as heat is not a commodity.

You keep bringing this topic up. I remember the last time and I'm not going to search and link it, but if I remember correctly Solar submitted a video that debunks the whole GHE as flat earth physics and political climate science.

it was so cold this morning i saw a socialist with his hands in his own pockets