Question: What would happen if our planets temperature increased or decreased? How would it effect us?

Hayley Evers-King answered on 22 Mar 2013:

This kind of depends on how various things react to increased/decreased temperature.

The climate system is quite complicated, so the planet getting warmer doesn’t necessarily mean there would just be warmer temperatures everywhere. We could end up with more rain – warmer temperatures usually mean more evaporation, which has to fall as rain somewhere – in some colder areas this actually means more snow when it gets warmer! We might expect more droughts, floods and extreme storms (like hurricanes) in a warmer world.

There’s also other things that could happen in a warming world. One of the things I’ve looked at is how ice melting can effect ocean currents. It’s thought that if a lot of ice melts, the input of cold and fresh (not salty) water could slow down some of the big ocean currents! This could stop the heat that’s transported by these currents. One example of this is the Gulf Stream – which keeps the UK nice and warm whilst Canada is freezing! We have evidence that this has happened in the past.

More or less ice in a colder/warmer world can effect our sea levels. If the sea level rises, parts of the coastal areas in our world might be more prone to flooding and near coast ecosystems (fishery areas, mangroves and coral reefs) could be effected too!

As far as we go – all these changes in climate (whether colder or warmer) would mean we’d need to adapt our current way of life. It might mean that certain foods don’t grow in some areas any more – so farming might have to change. It might also mean there are places we can’t live because there is not enough water or floods and storms are too frequent! Dealing with all these changes might cost a lot of money, so some people have suggested that poor people might be most effected.