More than 15,000 scientists from 184 countries released a letter earlier this week warning about the escalating dangers of climate change.

The letter is meant to reaffirm another letter signed by more than 1,700 scientists 25 years ago. The nearly 10-fold increase in signatories illustrates the overwhelming scientific consensus on climate change and the urgency that is needed to address it.

"Since 1992, with the exception of stabilizing the stratospheric ozone layer, humanity has failed to make sufficient progress in generally solving these foreseen environmental challenges, and alarmingly, most of them are getting far worse," wrote the authors of “World Scientists’ Warning to Humanity: A Second Notice,” which was published in the journal BioScience.

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The scientists go on to enumerate the many ways that the environment is deteriorating. The burning of fossil fuels, industrial agriculture, and deforestation are the primary drivers of climate change and ecological decline, but overpopulation, growth-focused economies, pollution, overfishing and hunting of threatened species, and more, are all playing a role.

A sixth extinction has already begun, the scientists warn, and unless scientific advice is heeded, "many current life forms could be annihilated or at least committed to extinction by the end of this century."

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To reverse these grim trends, the group makes it clear that governments have to act fast. The only way that will happen, they write, is through overwhelming public pressure.

“To prevent widespread misery and catastrophic biodiversity loss, humanity must practice a more environmentally sustainable alternative to business as usual,” the letter says. “This prescription was well articulated by the world's leading scientists 25 years ago, but in most respects, we have not heeded their warning.”

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The letter points to the regeneration of the ozone layer as a sign that the world can come together to protect the planet.

The global decline in extreme poverty is another reminder that astounding things can be accomplished through political action, according to the scientists.

The best hope for action may be through the Paris climate agreement, which is the first-ever global arrangement for fighting climate change.

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There are several key actions that can be taken on a collective scale to improve the environment and slow climate change, the letter argues.

Restoring marine, terrestrial, and aerial environments, retaining natural forests and grasslands, reducing food waste, and rewilding areas will help animal and plant populations recover and increase carbon absorption by the natural world.

The scientists also urge the widespread adoption of plant-based diets to prevent pollution and resource-depletion from the meat industry.

Reducing fertility rates, divesting from fossil fuels, investing in green technologies, and reducing inequality are other critical components of climate action, the letter argues.

"Soon it will be too late to shift course away from our failing trajectory, and time is running out," the letter concludes. "We must recognize, in our day-to-day lives and in our governing institutions, that Earth with all its life is our only home."