The particles that go into the atmosphere from volcanoes do cause cooling but it only tends to last for a couple of years before the particles all drop out again back to the background level. You'd have to have really big volcanoes going off all the time into the upper atmosphere to really have an effect like that.

We do actually have our own volcanic effect because industry also puts sulfate aerosols a little bit like a volcano into the atmosphere and that is actually helping to keep us a little bit cooler than we would be otherwise. And so that's actually a concern. When we stop burning dirty coal, which produces sulfur dioxide we'll actually make things a bit worse for a while before they get better.

'm afraid I can't even give you comfort there. Although parts of the Antarctic haven't shown a very strong warming yet, maybe because they're so isolated from the rest of the atmosphere, the Antarctic Peninsula for example, has been warming very fast. It's one of the places that has been warming the most rapidly. We now think that probably is related to global warming. We weren't really sure before because despite what you may think, we Scientists are cautious people. So the rest of the Antarctic hasn't yet shown a very strong cooling but the models suggest that it will. It is actually true that the ice sheets under warming probably will get thicker at first because what happens is around the edges where it's warmest, it will start to melt. But in the centre the temperature is nowhere near that, so it won't start to melt in the centre and you get a little bit more snowfall when it's warmer so that does make it a little bit thicker in the centre. Unfortunately all the predictions are that what happens at the edges wins.

If you look at the way people eat and the length of time they live in the Mediterranean, this gives rise to a thing called the Mediterranean paradox, or the French paradox. People there seem to live a lot longer than they ought to because they eat very fatty food. But the fats that they do eat are of a certain type, things like olive oil. Olive oil is very rich in a type of fat called mono-unsaturated. When we talk about fats we talk about long chains of carbon atoms linked together. You can either have one bond between one carbon atom and the next, or sometimes you can have a double bond. And if you have lots of single bonds between them, then that's saturated fat, and it's bad for you. And the reason it's bad for you is that all the carbon chains can get very close together and stack up very neatly. This forms a very solid block of fat. It's not very chemically exciting and it clogs your arteries up. If you have things like olive oil, they have a double bond, which gives the chain a kink. So when you try to press oil molecules together they don't stack up very neatly. They don't form a solid block of lard, they're much more chemically exciting and this is why they're better for you.

CFCs are actually everywhere in the atmosphere and not just over the poles. But over the poles where the CFCs are coldest, you get ice particles, which allow the ozone depleting reactions to occur. So it's not that the CFC concentrations are different, it's just what happens to them. Because Antarctica is completely isolated and surrounded by ocean, you get a whirlpool effect in the atmosphere there which has a concentrating effect. The depleted ozone therefore stays put rather than mixing in with the rest of the atmosphere.

I imagine it's something to do with the weight of the wing cases of the ladybird, that weigh it down and cause it to collapse, and also something to do with the muscle structure. When they die they relax and the tendons and things must retract the legs. When insects die there is also an element of drying, and dried things tend to shrink a bit and contract and go into their most compact shape