The United Nations Climate Change Conference of Parties (COP21) in Paris is only a few weeks away. This global conference is our last chance to tackle catastrophic climate change. If the negotiations fail, there is no plan B - COP21 is effectively the end of the line.
In 1992, the UN Framework Convention on Climate Change was established to "stabilize greenhouse gas concentrations." Since then we have endured failed negotiations, broken promises, distant targets and shattered hope.
When world leaders meet for COP21, they must commit to effective and practical steps to prevent average global temperature increases of above 2 degrees Celsius. According to climate scientists, existing pledges by governments fall short of achieving this target, which itself is woefully inadequate. Even now many countries are starting to feel the devastating impact of climate change.
In the last 250 years, average global temperatures have already increased by 1 degree Celsius. The Intended Nationally Determined Contributions (INDCs) submitted by governments up to now, even if fully implemented, will actually increase warming to around 2.7 degrees Celsius above preindustrial levels by 2100. For decades, scientists have been warning us about the threats of climate change and its impact on the world: how parts of Africa, South Asia and Latin America will heat up more and more, with temperatures becoming increasingly intolerable; how rising sea levels will endanger billions of people, particularly those in low-lying countries such as Bangladesh, the Marshall Islands and the Maldives, as well as people in cities such as Tokyo, Shanghai, New York and London; how melting glaciers will flood river valleys and then, when they have disappeared, unprecedented droughts will occur.
Pope Francis issued a dire warning to the world when addressing the UN General Assembly: "The ecological crisis, and the large-scale destruction of biodiversity, can threaten the very existence of the human species."
World leaders can no longer ignore the warnings. COP21 is their last chance to prevent catastrophic climate change. They must deliver a comprehensive, just and legally binding climate agreement with adequate provisions for mitigation, adaptation, loss and damage, Green Climate Fund financial investments, technology development and transfer, and implementation mechanisms, with safeguards for traditional communities, indigenous peoples' rights and an emphasis on human rights and gender equality. They must commit to ensure the integrity and resilience of natural ecosystems, restore degraded and deforested land and transfer subsidies from the fossil fuel and nuclear industries to renewable energy.
We must not forget that we are fighting for our survival, the survival of our children and our children's children - the survival of future generations. Beyond that, we are fighting for the preservation of all life on earth.
We appeal to world leaders to do what is necessary to protect and safeguard life on earth - to commit to carbon dioxide reduction targets in line with the best available scientific knowledge to prevent catastrophic climate change.
I urge you to go to MoveOn.org and sign this Appeal to World Leaders.
Since the launch of the petition, we have received a tremendous response and have the support of a wide cross section of the global community, including political leaders, nongovernmental organization directors, scholars, actors, artists, filmmakers and more, including Frederic Mion, president of the Paris Institute of Political Studies; Craig Calhoun, director of the London School of Economics; Archbishop Emeritus Desmond Tutu; actor Patrick Stewart; comedian Stephen Fry; singer Annie Lennox; architect David Chipperfield; and from the art world: Thaddaeus Ropac (Galerie Thaddaeus Ropac); Julia Peyton-Jones (Serpentine Gallery); Nicholas Logsdail (Lisson Gallery); Marina Abramović; Jules de Balincourt; Ross Bleckner; Francesco Clemente; Tracey Emin; Ghazel; Antony Gormley; Anish Kapoor; Andreas Kronthaler; Richard Long; Robert Longo; Jason Martin; Yoko Ono; Elizabeth Peyton; RETNA; Raqib Shaw; Francesco Vezzosi; Bill Viola; Not Vital; and Vivienne Westwood.
See our complete list of supporters at MoveOn.org and join us in urging our leaders to commit to carbon dioxide reductions in line with scientific recommendations by signing our Appeal to World Leaders.
This piece was originally published at The Huffington Post.