Vancouver Olympic organizers say they need tourists flying to the Games to pick up their share of carbon offset expenses. (CBC)

Vancouver Olympic organizers are looking to spectators travelling to the Games to help fulfil the goal of staging the greenest Olympics ever.

VANOC intends to put on a carbon-neutral Games but said Thursday it would need help to buy carbon offsets for the estimated 268,000 tonnes of emissions the Games will be responsible for.

Almost half of that carbon footprint — 130,000 tonnes — will be generated by Olympic spectators travelling to Vancouver to attend the Games.

The organizers said they would encourage Games tourists to buy carbon offsets to balance the environmental impact of their travel.

"Because of the nature of individuals taking responsibility for where they want to travel, we're trying to make it easy," said VANOC corporate sustainability officer Ann Duffy.

Duffy said the hope is that, "people include this in some of their decisions to travel and enjoy the Games."

Tourists directed to website

A VANOC-sanctioned website — offsetters.ca — was suggested as one place where tourists could calculate and pay for their carbon offsets.

The website acts as a brokerage, connecting individuals and corporations to offset projects to which they can contribute.

Such projects include programs in which carbon-absorbing tracts of forest land are set aside for certain periods of time, making up for activities that generate greenhouse gases. Other projects intend to capture excess carbon dioxide from the atmosphere and store it underground.

A family of four flying to Vancouver from Toronto that wanted to participate in the program would pay about $140 for their offsets, according to the website.

The same family driving from Kamloops, B.C., and back would incur just a $5 offset.

VANOC said it would only take responsibility for offsetting the estimated 118,000 tonnes of direct emissions from the Games that have been generated by venue construction and athletes' travel.

"One has to draw the line somewhere," said Duffy.

"We're doing some heavy lifting in terms of covering the footprint for our direct operations."

VANOC anticipates that sponsors and governments will pick up the offset costs for the estimated 20,000 tonnes of carbon emissions not paid for by organizers and Games tourists.