A cart laden with casualties of the French Revolution of 1848 is driven past The National in Paris passing a lamenting crowd.

Using the past to predict the future

How do we know what is going to happen next to the Earth – and to humans?

One crucial feature of science is that it makes evidence-based predictions.

This evidence comes from several sources. Data can be collected to characterise the current state of the planet, and recordings over time can reveal short-term trends. Controlled experiments can tell us how different factors interact with one another (how chemicals react, how organisms respond, etc.).

In addition, various techniques can be used to reveal what Earth was like in the past, and how and why it has changed. Then, principally through the use of computer models, we can simulate what may happen next.

Models have been used to map out possible futures for the planet. They can also be used to assess how these possible futures may affect human health.

Lead image:

Rapid climate change may significantly increase the risk of social unrest. The French Revolution of 1789 followed several years of harsh weather and food shortages, possibly linked to the eruption of the Laki volcanic system in Iceland in 1784.

Wellcome Library, London CC BY


Further reading

About this resource

This resource was first published in ‘Health and Climate Change’ in January 2009 and reviewed and updated in September 2014.

Statistics and maths, Microbiology, Cell biology, History
Health and Climate Change
Education levels:
14–16, 16–19, Continuing professional development