Some people wonder, “Why is global warming happening down/up there at the poles if it is because of man? There aren’t too many of people living there to cause any problem.”

Good, common-sense question.

But there’s actually a solid answer to it that suits both alarmists and skeptics about anthropogenic global warming.

Local anthropogenic warming, usually called “urban heat island effect” (UHI), is the localized warming stemming from increased absorption of incoming solar energy by blacktop, buildings, etc., and by the release of heat from air conditioning, vehicles, and industrial activities. It varies according to population density and is indeed local. There’s little of that near the poles.

But global anthropogenic warming is truly global and is the consequence of greenhouse gases’ absorption and re-radiation of infrared (heat) radiation bouncing back from the earth’s surface toward space. When the greenhouse gases re-radiate the heat, some of it goes back down toward the surface, warming it. Since the gases circulate around the globe, their warming effect is actually global.

But it’s not equal all over the globe. For a variety of reasons, it’s greater in high latitudes, in winter, and at night than in low latitudes, in summer, and in the daytime. This means warming is more marked toward the poles, in the winter, and at night than toward the equator, in summer, and in the daytime. The result is that, even though the polar regions have few people living in them, they warm more than the temperate and equatorial regions.

But that’s good news. It means growing seasons lengthen, killer frosts end earlier in spring and begin later in fall, so crops and other vegetation grows better toward the poles, while the already warmest areas of the earth experience comparatively little warming.