In the beginning, none of the greek gods seasons can be compared to Apollo's summer. Apollo being the god of the sun he brought it down every single year. At this time his smile was said to be as bright as the sun itself. Poseidon was never in agreement with Apollo because he was always envious of him and wanted a season like it.
The olympian gods looked down upon the earth as they saw the humans in bliss. As the humans are in happiness so are the gods. Thats what makes the gods different from the titans. All the gods seemed to be in amusement but one. The all mighty lord of the seas Poseidon.
At first Poseidon hardly noticed the humans and was just mad that Apollo was happy. As more and more and years past he got more jealous of Apollo . So Poseidon went to his brother Zeus who was in debt of Poseidon because he had let Athena his daughter have the capital of Greece . So Zeus let him have half of summer. Apollo heard of this and ran amok, and was out for his uncle.