What is climate change?
Escalating levels of atmospheric greenhouse gases are trapping more heat in the atmosphere and raising the global average temperature.
The earth is only able to maintain its life-supporting global average temperature of 14ºC because of the natural phenomenon known as the ‘greenhouse effect’. This is the balance between the solar radiation reaching Earth from the Sun and the amount of energy escaping Earth to outer space in the form of invisible infrared radiation.
The current global average temperature is higher than any previous levels over the last 420,000 years and temperatures have risen by approximately 0.6ºC over the 20th century. This may not sound very much but partly because this includes much higher regional rises such as in the polar regions (which have warmed by as much as 3ºC) it has already been enough to affect the planet’s climate patterns, with many knock on effects to people, wildlife and habitats around the world.
For example, many British birds are breeding earlier than they used to with a risk of falling out of time with the abundance of their invertebrate prey in the Spring, as has occurred in the Netherlands. This can mean that chicks will not have enough food to grow and bird levels then fall.
To solve the problem of global warming and climate change, scientists called climatologists must find methods of understanding it. They are studying the climate by examining data from archives, weather stations and satellites, as well as using computer models to make predictions.
Models are theories of how the climate works, but our atmosphere is a fiendishly complicated system. Climatologists test their models by working backwards in time to see if they can accurately predict things we know have already happened, such as our last ice age. If a model works well, they can be more confident in its predictions for the future.
There are modelling centres all over the world, and the UK Met Office Hadley Centre is one of the most advanced. We’re using their model here because they are the best predictions we have to understand what climate change will do to the wild habitats and animals that we at the Zoological Society of London exist to protect. Read more about computer modelling.