Part of the show Forecasting Weather and Climate
Bernie in Peterborough asked:
How does the weather affect weaker ocean currents?
In terms of the ocean affecting the weather, the ocean has a very strong influence on seasonal weather. If you're talking about needing weather predictions several months ahead, then you do very much need to look at the ocean temperatures. In fact, if we look at this last winter, it's been incredibly dry here in the UK. That's been closely connected to the fact that we've had incredibly warm sea temperatures in the tropical Atlantic. If we look back to the autumn we had lots of hurricane activity including the one in New Orleans, and that was also connected with sea surface temperatures. For European winters, you have one of two situations. You either have the case where you have a very strong jet stream that brings all the storms across the Atlantic to the UK. In those situations you'll typically have warm, wet winters. The other situation is where you have a much weaker jet stream and the storms tend to get deflected up north or down south. In those situations you typically have a cold, dry winter in the UK. Whether or not you're in one or the other situation is largely modulated by the sea surface temperatures are like in the Atlantic Ocean.