Scientists from more than 180 countries have signed a letter warning humanity of man-made climate change and the devastating effects it could have on the planet.
More than 16,000 scientists have attached their names to the letter, published Nov. 13 in the scientific journal BioScience.
The letter, titled "World Scientists' Warning to Humanity: A Second Notice," is a follow-up to the letter of the same name published in 1992.
More than 1,700 scientists signed the original letter, which warned "human beings and the natural world are on a collision course," according to KTLA.
William Ripple, professor of ecology at Oregon State University, decided to write a follow-up letter to show that the warnings of the first letter had largely been ignored.
"To prevent widespread misery and catastrophic biodiversity loss, humanity must practice a more environmentally sustainable alternative to business as usual," Ripple wrote in the new letter. "This prescription was well articulated by the world's leading scientists 25 years ago, but in most respects, we have not heeded their warning."
"Soon it will be too late to shift course away from our failing trajectory, and time is running out," he continued. "We must recognize, in our day-to-day lives and in our governing institutions, that Earth with all its life is our only home."
The letter also calls for people to demand action from their governments. Entrenched climate change deniers in government can only be moved to action through "organized grassroots efforts," the Ripple writes. This pressure must come not only from scientists, but "media influencers" and ordinary citizens, according to the letter.
In the letter, Ripple holds up the reduction of "ozone-depleting substances" as an example of how humans can improve the environment when they work together.
The Earth's ozone layer has seen steady improvements since the 1987 United Nations Montreal Protocol which called for a reduction of harmful gasses released by aerosol cans and refrigerants, according to KTLA.
Ripple also lists improvements in the rate of deforestation and the growth of the renewable-energy industry.
"We have learned much since 1992, but the advancement of urgently needed changes in environmental policy, human behavior, and global inequities is still far from sufficient," he writes.
Despite the potential peril described in the letter, Ripple says he's an optimist.
"My hope is that this letter triggers a worldwide conversation about these environmental and climate trends and perhaps more fundamentally that it can raise people's awareness of the seriousness of global environmental problems so we can come together," he said, according to KTLA. "It is so important to work together as a human race to make a sustainable future on planet Earth."
Sources: KTLA, BioScience / Featured Image: Alfred T. Palmer/Library of Congress/Wikimedia Commons / Embedded Images: Nils Ally/Wikimedia Commons, PxHere