DAME Elisabeth Murdoch has written to Michelle Obama inviting her to join an environmental “call to arms” she is launching, called Influential Women for Climate Change Action.

In the letter, the latest signal by the Murdoch family of its commitment on climate change, its matriarch, who turned 100 in February, tells the US first lady the world is facing a “global emergency”.

Dame Elisabeth says the group will be a “campaign to enlist influential women in Australia and around the world to take the lead in protecting and nurturing Mother Nature by encouraging people to reduce their emissions”.

“Having seen many challenges in my 100 years, I believe it is time to add my voice to what could be termed ‘a call to arms’, a call for people around the world to act now to reduce our impacts on the planet,” Dame Elisabeth writes.

“It is plain to see humanity cannot go on living beyond the planet’s means. Climate change is not the first manifestation of this, just the latest and most serious. As recent extreme events like the Victorian fires and the Queensland floods demonstrate, it threatens the future for generations living now, as well as for those to come.

“From a personal point of view, I have lived long enough to have a great-great granddaughter starting life, and I wonder what her world and her life will be like if we do not act in her defence now.”

Dame Elisabeth tells Ms Obama of the Global Green Plan Foundation, a project of which she is patron, which is developing an environmentally focused school curriculum warning of the dangers of climate change.

The curriculum, aimed at middle-years students, was launched yesterday at Williamstown High School in Melbourne, where Dame Elisabeth was described by foundation president Hal Hewett as “the world’s only centenarian climate change campaigner”. The curriculum, Living in 2030: An Experiment in Survival, backed by Fuji Xerox, invites students to imagine the world in 2030 if nothing is done to curb “economic rationalist thinking” with its “lunatic slogan, ‘Grow at all costs”‘ and to find solutions to global warming and diminishing resources.

Dame Elisabeth was joined at the launch by actress and green campaigner Isabel Lucas.

Dame Elisabeth’s letter was sent to Ms Obama last week. Mr Hewett said it was now being considered “in both the East Wing and the West Wing” of the White House.

In November 2006, News Corporation chairman Rupert Murdoch announced a change of heart on climate change, saying that while he remained sceptical of doomsday scenarios, “the planet deserves the benefit of the doubt”. In May 2007, he said News Corporation, owner of The Weekend Australian, would be carbon neutral by 2010, saying climate change posed “clear, catastrophic threats”.