Less than an hour after the previous ship sailed another is sailing to Asia.  It is low in the water as it is full of coal.  At the same time the next ship is moving into the harbour, it is high out of the water as it is empty. Doh. Several tug boats gather nearby to see it into the port.

A helicopter is barely visible landing on the deck to pick up the pilot who took the ship out of the harbour.  Another pilot is already aboard the incoming ship.

In no time, the latest ship and tugs are in the harbour and almost in the channel to the coal loading docks where a whole line of ships are filling up with loads of black fossil fuel.