Question: how does the sun create our weather

Karen Bacon answered on 14 Nov 2013:

So this is another tough one! Weather is something that happens day-to-day (as you know) and isn’t really caused directly by the sun, except that the sun of course keeps our planet hot enough for us to live on. The sun gives energy to our atmosphere and then for a whole lot of very complicated interactions between the atmosphere, the oceans and the land we get weather that changes day-to-day. The science of predicting the weather is incredibly complex and uses a type of maths called “chaos theory” which should tell you something about how hard it is! Weather can also be affected by human activity – for example burning lots of fossil fuels can create smog, which will then hang around in the sky and can increase rainfall. Cities are always hotter than the surrounding countryside (this is called the urban heat island effect) because of the energy created by people moving around, using electricity and driving cars, buses, vans etc.
So although the sun is ultimately responsible, weather is very complicated and caused by lots of different interacting factors. The orbit of the Earth also helps to cause weather – winter and summer are due to changes in the tilt of Earth’s orbit, and this changes the weather we get for a few months. The Earth also has long-term cycles in its orbit that can effect climate (climate is different to weather – weather happens day by day but to have a particular climate you need broadly similar weather for around 30 years. So to say that the climate is getting hotter or colder, you need at least 30 years of increasing or decreasing temperatures). The orbital cycles are called Milankovitch cycles are can effect climate on 10,000; 21,000 and 41,000 year cycles – they were partly responsible for the last set of ice ages.