Good detailed explanations of key topics
Climate and Earth’s Energy Budget (NASA)
This is a good explanation of solar energy input to and energy loss from the earth.
The Earth’s climate is a solar powered system. Globally, over the course of the year, the Earth system—land surfaces, oceans, and atmosphere—absorbs an average of about 240 watts of solar power per square meter.
Satellite Orbits (EUMETSAT)
There are many satellites in orbit. This explains the two main ways of positioning satellites: those that always monitor the same area on the earth all the time, and those that scan the whole earth over time.