CO2. Can I ask you to do a visual representation of all that transparent, clear gas? This would be like a 1 100th scale model. You can generate a 10,000 dot grid online- that's 1% of 1 million. Color 3 and 1/2 of those dots a lovely green (1% of the so called level of "natural" CO2), that's the so called "normal" level of CO2 within the 10,000 dots, or a representation of 1% of the atmosphere. Now color that 1/2 dot violent red to represent 50 parts per million of deadly, climate changing manmade CO2. It becomes painfully obvious that 50 parts per one million parts is insignificant, and then ask, how does a transparent molecule reflect anything only one direction, back to earth. Physics demands that it would also reflect an equivalent amount of heat back into space, so it's self balancing.
Now if you can still find it on NASA.gov, look for satellite imagery of CO2 concentrations. Downwind of the Amazon rainforest, where large volumes of organic material are decomposing and releasing CO2 into the atmosphere, CO2 levels are measured in the 3000 to 4500 ppm range. Meanwhile on the poles, where there is no organic decomposition, CO2 levels read near zero. There is no such thing as an average CO2 level because it is dynamic, seasons are in opposition in the northern and southern hemispheres. The concept of an average world temperature is in the scientific definition of the word, absurd. Doing a simple average of the highest recorded temperature on earth in Death Valley, and the lowest recorded temperature recorded at the South Pole would suggest the average temperature of earth is ZERO degrees, again, absurd. On my property I have a swale on the west side of the property that descends from a 10,000 foot mountain. 300 feet to the west it is about 15 ft. higher in elevation and relatively flat. At 6:00 am, I measure a 10 degree difference from one side to the other as cold air settles. At noon there is a 2 degree difference, in late afternoon, warm air is rising up the swale and it is 9-11 degrees warmer than the flat side. If I were to state an average temperature for my 10 acres, it would be meaningless, since it all depends on location. TO try to estimate an average temperature on earth would require over a trillion data points, and the result would be useless. What difference would an average temperature of +55 degree mean in Antarctica where it never gets over 60 below zero?