Carbon Dioxide and Global Warming

Pieter Tans is a senior scientist at the National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory. He recently addressed the problem of "If carbon dioxide makes up only a minute portion of the atmosphere, how can global warming be traced to it? And how can such a tiny amount of change produce such large effects?" My congratulations to Mr. Tan for addressing this problem in a direct manner, and which has been ignored by so many so-called scientists.
The essence of Mr. Tan's reply is that heat coming from the sun collects at the Earth's surface and also radiates back to outer space, unimpeded by nitrogen and oxygen, which are the main components of the atmosphere. However. Carbon dioxide has the unusual property of being an excellent insulator and will not allow loss of heat from the earth to the stratosphere.
I addressed a reply to Mr. Tans through Scientific American as follows:
Mr. Tans,
    I believe you may be incorrect in your mechanism concerning greenhouse gases.
      I propose this alternative: Incoming radiation from the Sun passes through the atmosphere unimpeded. When that radiation strikes a solid surface, at least a portion of it is converted to heat. During the day, that heat accumulates, as indicated by rising Earth's surface temperatures. At night, the heat tends to leave the Earth's surface and pass into interstellar space, which is much colder than the Earth's surface. All gases of the atmosphere act as insulators to deter the loss of heat from the earth's surface. Those gases, including especially nitrogen and oxygen are greenhouse gases which make the earth much warmer than it would be without an atmosphere.
      The heat insulation properties of the gases under consideration are well-known through laboratory measurements of thermal conductivity. The lower the thermal conductivity, the better is the gas as an insulator. Measurements of thermal conductivity are in mW/m.K. The figures are nitrogen 24.0, oxygen 24.4, and carbon dioxide 14.7. This means that carbon dioxide is almost twice as good an insulator to the passage of heat from the Earth's surface than either nitrogen or oxygen; i.e. a better greenhouse gas. However the atmospheric concentrations of nitrogen and oxygen are respectively 78% and 21%, while the atmospheric concentration of carbon dioxide is only 0.05%. This means that although carbon dioxide is a better insulator to the loss of heat from the Earth's surface, the fact that it constitutes only 0.05% of the atmosphere, makes its effect insignificant.