Answer:
1) "Watch Rangitoto do it's /Auckland in high summer bit"
2) The connotation there is somewhat negative, since the word 'crashed' is used, as well as the connotation being that this silence is fully surrounding, since something, when it crashes, usually hits heavily.
3) "We do all the things a man and a boy can do at the shore" supports the idea that the speaker goes to the beach in order to spend time with his son, not just to cool off.