What are the lights in the skies for?

Answer From The Annual Reading Schedule - Week 1 Notes For Genesis: For signs, appointed times, days, years, and light on the land (Genesis 1:14-15).

Contrary to the idea that some people incorrectly teach that the 'barley harvest can't be used related to the Biblical New Year' or that 'the harvest is unrelated to the start of the New Year', we see very clearly from Genesis 1:15 that lights are in fact given to give light on the land (Genesis 1:15). Everyone is focused on Genesis 1:14 and forgets that Genesis 1:15 says the lights are to be on the land. What happens when lights are on the land? People tend to think "light" is only related to the visual aspect of light – but light, however, has a heat component. 'Light on the land' means heat from the light also on the land – which therefore means heat on the land to cause the Winter to change to Summer at the Appointed Time of the Harvest. The Harvest cannot come unless the land warms up from the light that is given to be light on the land as Genesis 1:15 states.

Therefore – the Barley Harvest condition does, in fact, have a direct and very Scriptural correlation and linkage directly to the Light from Genesis 1:14-15. It is an error to say that someone using the Barley Harvest to help figure out the start of the New Biblical Year is "not using the light" because that very Harvest is an exact derivative from the Genesis Light on the land and is directly tied to the land mentioned that the light goes on in Genesis 1:15.