Cruise ships have to meet very high requirements of all the different countries where they sail to or getting close to. Especially European countries have requirements which are often far beyond their land based developments or any requirements in Northern America. As a result modern cruise ships i.e. built at Meyer Werft in Germany are extremely environmental friendly - much more than any costal region or city along the American East Coast where uncountable vacationer waste resources, uncontrolled destroy nature environments and pump the sewage without treatment into the ocean.
The green roof on Celebrity Cruise ships demonstrates modern green roof technology to more than half a million people every year - more than any other projects and more than any other advertising from green roof associations. All these guests are also introduced to all other advanced technologies on the ship which are decades ahead of most LEED certified buildings in the US.

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