Adams was referring to expected changes in January 2009 of US national policy after the end of the Bush administration, which has opposed emissions caps.
The "other American" message will be delivered by headline spokesmen: California Governor Arnold Schwarzenegger, addressing the conference by live video link on Friday, and New York Mayor Michael Bloomberg, speaking in person that same day.
The governor and the mayor will follow by one day the appearance of climate crusader and former vice president Al Gore, fresh from his Nobel Peace Prize award ceremony in Norway.
This competition between national and state governments doesn't faze the veteran chief US climate negotiator.
"It gives the world the opportunity to see the diversity of views in the US," said Harlan Watson.
Besides Adams's 30 Californians, larger than many countries' delegations, a consortium of Northeastern states is represented here by a New York state official, and local governments, from Annapolis, Md., to King County, Wash., have sent chief executives or other envoys.
They began arriving last weekend, midway through the two-week, 180-plus-nation conference, and immediately entered into a schedule of presentations and meetings with European delegates and others, to report what they're doing at home and to learn what more might be done to head off the impacts of climate change.
In California, the threat of severe water shortages and other potential problems due to rising temperatures led the Republican governor and his Democratic-led Legislature last year to enact legislation to reduce emissions by utility plants, oil refineries, cement factories, and other major industries by an estimated 25 percent below what they otherwise would be in 2020.
The state is establishing a cap-and-trade system by which businesses can buy and sell emissions credits - selling extra allowances if they come in under their quotas and buying them if they overshoot the ceiling. The European Union established the first trading system under the Kyoto Protocol, the emissions-reduction agreement rejected by the United States.
Five other Western states, meanwhile, have joined California in a Western Climate Change Initiative, setting a regional goal of 15 percent greenhouse-gas cuts below 2005 levels by 2020.
The European Union, by contrast, has committed to 20 to 30 percent reductions below 1990 levels by 2020.
In the Northeast, New York, Massachusetts, and eight other states have agreed to reduce power plants' carbon dioxide emissions by 10 percent below 2005 levels by 2015.
They will launch a cap-and-trade system in 2009.
Five Midwestern states and Canada's Manitoba Province last month announced their own plan for a regional cap-and-trade plan.
State officials are consulting across regional lines and with the European Trading System to harmonize such elements as how to measure emissions, account for credits and trades, and capitalize the market - by grants of credits to industries, as in Europe, or by auctioning off credits, as US states envision.
