These are very good questions! The “more of” radiation in my remarks means a larger fraction of the surface emission escaping to space, not the absolute amount of radiation.

I enjoyed reading this article.

I found the following statement confusing: “For example, the Arctic has drier air than most regions,” explains Yi. “With less moisture to trap the heat, more of the Earth’s surface radiation escapes into space here than in other regions2.”

On average, the polar regions are the coldest places on Earth and hence emit the least OLR. The observed zonal-annual average OLR is about 120W/m2 over south pole and about 160W/m2 over north pole, and increases to about 270W/m2 in the tropics. I am confused about what you meant by ‘more of the Earth’s surface radiation escapes into space here than in other regions’.

Perhaps you are just emphasizing the role of greenhouse effect of water vapor and not implying that this greenhouse effect is dominant over the temperature effect?