'Valuing science'

"His appointment should send a signal to all that my administration will value science. We will make decisions based on the facts, and we understand that facts demand bold action," Obama said.

Browner is an ally of Al Gore, the former vice-president turned Nobel Prize-winning environmental campaigner, and headed the Environmental Protection Agency (EPA) in Bill Clinton's administration.

Carol Browner is a former Environmental Protection Agency head [AFP]
Obama also announced his choice of Lisa Jackson, former head of New Jersey's environmental agency, as EPA administrator.

"We can spark the dynamism of our economy through a long-term investment in renewable energy that will give life to new businesses and industries with good jobs that pay well and can't be outsourced," he said.

"We must also recognise that the solution to global climate change must be global," he added.

Obama also met members of his new national security team on Monday, in one of several meetings he is expected to hold with his national security team between now and when he takes office on January 20.

His transition team said the focus of the meeting was on challenges around the world, so they are prepared when the new administration takes office.