Earth is home to millions of species but just one dominates it. Us.

Our cleverness and our activities have modified almost every part of our planet.

We are having a profound impact on it.

Our cleverness and our activities are now the drivers of every global problem we face.

And every one of these problems is accelerating as we continue to grow towards a global population of 10 billion.

We emerged as a species about 200,000 years ago. Just 10,000 years ago, there were 1 million of us.

By 1800, just over 200 years ago, there were 1 billion of us. By 1960, 50 years ago, there were 3 billion of us. There are now over 7 billion of us.

By 2050, your children, or your children’s children, will be living on a planet with at least 9 billion of us. Some time towards the end of this century, there will be at least 10 billion of us.

We got to where we are now through a number of civilisation and Society shaping events, most notably the agricultural revolution, the scientific revolution, the industrial revolution, the health revolution.

Consequences of our growth are starting to show. Water, a vital resource we had thought of as abundant, has become something that had the potential to be scarce.

The climate is one of the Earth‘s fundamental life support systems, one that determines whether or not we are able to live on this planet.

It is generated by four components: the atmosphere (air we breathe); the hydrosphere (water); the cryosphere (ice sheets and glaciers); the biosphere (plants and animals).

Our activities have started to modify every one of these components. Our emissions of CO₂ modify our atmosphere. Our water use modify our hydrosphere.

Rising atmospheric and sea-surface temperature modify the cryosphere, most notably in the unexpected shrinking of the Arctic and Greenland ice sheets.

Our increasing use of land, for agriculture, cities, roads, mining modify our biosphere. We had started to change our climate.

As our numbers grow, we continue to increase our need for far more water, far more food, far more land, far more transport and far more energy.

As a result, we are accelerating the rate at which we are changing our climate.

Our activities are not only completely interconnected with but now also interact with, the complex system we live on: Earth.

It is important to understand how all this is connected.