With every passing day, evidence of the need for change in the way we feed ourselves mounts. The latest warning comes from a letter signed by an unprecedented 15,000 scientists warning that humanity faces ‘vast’ misery if it doesn’t urgently adopt environmentally sustainable alternatives to business-as-usual, not least in the areas of energy, food and farming.

Issued on the 25th anniversary of the original “World Scientists' Warning to Humanity”, this ‘second warning’ says that the picture is far, far worse than it was in 1992, and that almost all of the problems identified then have been exacerbated.

Writing in the journal Bioscience, the project team, led by Professor William Ripple of Oregon State University, said “We are jeopardizing our future by not reining in our intense but geographically and demographically uneven material consumption and by not perceiving continued rapid population growth as a primary driver behind many ecological and even societal threats”.

Among the negative 25-year global trends noted in the article are:

A 26 per cent reduction in the amount of fresh water available per capita
A drop in the harvest of wild-caught fish, despite an increase in fishing effort
A 75 per cent increase in the number of ocean dead zones
A loss of nearly 300 million acres of forestland, much of it converted for agricultural uses
Continuing significant increases in global carbon emissions and average temperatures
A 35 per cent rise in human population
A collective 29 per cent reduction in the numbers of mammals, reptiles, amphibians, birds and fish

The scientists warn that we have “unleashed a mass extinction event”, perhaps the biggest since an asteroid wiped out the dinosaurs.

In my book, Dead Zone: Where the Wild Things Were, I document how the way we feed ourselves has become a dominant activity on the planet, affecting wildlife and the natural ecosystems on which our existence depends. Nearly half the world’s usable land surface and most human water use is devoted to agriculture.

15,000 Scientists Issue Dire Warning to Humanity: ‘Time is running out’