At one time they were the most literate people in America. Other groups with a large number of speakers and classes and programs to learn it are largely in Canada. Inuit is even the language of government in one province. I would choose a Canadian version of Inuit unless you have access to Greenland.
Answer is Ionosphere. The ionosphere is a layer of ionized air in the atmosphere extending from almost 80 km above the Earth's surface altitudes of 600 km and more. Technically, the ionosphere is not another atmospheric layer. [ It occupies the same region of the upper atmosphere as the thermosphere. In this region of the atmosphere the Sun's energy is so strong that it breaks apart molecules. and atoms of air, leaving ions (atoms with missing electrons) and free-floating electrons. The ionosphere is the region of the atmosphere where the aurorae occur.
Part of this radiation is directed towards the surface, warming it. On Earth, solar radiation at the frequencies of visible light largely passes through the atmosphere to warm the planetary surface. The surface itself emits energy at the lower frequencies of infrared thermal radiation. Infrared radiation is absorbed by greenhouse gases in the atmosphere. These gases also radiate energy, some of which is directed to the surface and lower atmosphere.