The exact impact on commercial real estate is unknown. New Jersey is already famous for its tough environmental standards for developers. Builders nationwide have been favoring green-building materials and designs recently, both for their energy-efficiency and their selling ability to buyers and tenants.

New Jersey already is ahead of most states in preserving land. Most of the undeveloped land in the state is already off-limits by the Pinelands and Highlands legislation.

The signing comes a day before the Live Earth concert at Giants Stadium, which Gore will be hosting. Other Live Earth events will be held simultaneously at seven other international locations: London, Hamburg, Shanghai, Tokyo, Rio de Janeiro, Sydney and Johannesburg. A team of scientists on Antarctica will broadcast in, giving participation from all seven continents.