Ge 8:20 Then Noah built an altar to the LORD, and took of every clean animal and of every clean bird, and offered burnt offerings on the altar.

21 And the LORD smelled a soothing aroma. Then the LORD said in His heart, "I will never again curse the ground for man's sake, although the imagination of man's heart is evil from his youth; nor will I again destroy every living thing as I have done.

22 "While the earth remains, Seedtime and harvest, Cold and heat, Winter and summer, And day and night Shall not cease."

Moses is teaching his Israelite readers here that worship on their part is the proper and right response to God's deliverance and salvation. Just as God delivered Noah from judgment and offered God worship, so the Israelites should respond in like fashion.

Moses here is encouraging them to voluntarily offer God worship through the offerings of clean animals as burnt offerings to Him. It pleases God.

Moses also teaches here that the seasons are result of God's decree and ordination. The Israelites therefore are not to worship other gods to somehow affect seasons and weather conditions.