An international team of scientists has again appealed to politicians with a demand to recognize the danger, hanging over humanity.

Biologists, ecologists and theorists of complex systems from the USA, Canada, South America and Europe, which was headed by Anthony Barnoski, Professor of integrative biology at the University of California at Berkeley (USA), emphasize that the turning point, after which the biological system of the Earth may change beyond recognition, is a reality, not apocalyptic hysteria or far-fetched speculation. This is a purely scientific question, a matter of debate.

The authors of the material, published in Nature, has strengthened her words about a hundred articles, painting crucial moments in the environmental history of the planet.

The concept of the tipping point was popularized in our days the canadian journalist Malcolm Gladwell respect of sociology, but it is based on the mathematical tools developed by Kenneth Wilson, winner of the Nobel prize in 1982.

In recent decades, scientists have found a number of signs of turning the situation in various natural environments, from ponds and coral reefs to whole regional systems like the Sahara desert, which is 5 500 years ago was a fertile pasture, and the Amazon basin, gradually turning into Savannah.

Traditionally it was believed that nature is in static equilibrium and changes happen very slowly. In fact, as shown by current research, this is a very dynamic system with a sort of the tides. Rapid temperature rise or, say, the emergence of a new source of nutrients and the system experiences a sudden transformation.

According to some researchers, something like that happened 540 million years ago during the Cambrian explosion, and much later, when just a few thousand years after the end of the ice age has blossomed human civilization.

But last change was caused by natural processes - by changing the chemistry of the ocean or the intensity of solar radiation. Today on the foreground there is the man, or rather seven billion people.

Our activity covers 43% of the land, but the consequences are felt by almost all the rest of the Earth. One third of the world's freshwater go to the satisfaction of human needs. 20% of what it produces nature, take all the same bipedal. By 2070, the rate of extinction of species threatened compared with the figures of the Cretaceous-tertiary extinction, and the average temperature will be higher than in the entire history of Homo-evolution.

We are so strong that they are able to change the climate and the environment not only on regional, but also global level. Therefore, scientists unofficially dubbed the current geological epoch, the anthropocene.

Everything indicates that a turning point may happen in the next century. At the local level it somewhere already passed.

However, not all experts agree that cascade local changes will inevitably lead to irreversible changes in the planetary scale. Mathematical modeling of complex systems shows that chaos is always there, and it does not necessarily mean a fracture of the entire system. At the same time, empirical studies of chaos in ecosystems almost not available, and therefore to judge to what degree local chaos safe for the planet, too early.

Anyway, the question remains: what do we do in a situation such uncertainty? Mr. Barnoski and his colleagues are urged not to risk, and to seek more effective methods of food production, refusal from fossil fuels, more rational exploitation of ecosystems and reduction of population growth. We still have time to choose the most comfortable way, without waiting for the need to take emergency measures, from which all have hard times.

Publication in the journal Nature timed to the UN Conference on sustainable development to be held on June 20-22 in Rio de Janeiro (Brazil).

Prepared according to Wired.