Circulation Cells
So why don’t the poles get colder and colder, and the equator hotter and hotter? In nature, systems tend towards equilibrium, that is to say, nature doesn’t like differences, so …
Course: Learn About Weather
Five unusual rainbows
There are a number of different types of rainbow to spot depending on the particular weather or atmospheric conditions. Have you seen any of these?
Visibility
This time-lapse video shows a foggy morning in Exminster, Devon, looking towards the river Exe. As the morning progresses, the fog gradually lifts and clears from Exminster, though persists long …
Pressure
Atmospheric pressure is the weight of air in a column above your head, we don’t think of air as having weight because we don’t feel it, but actually there is …
Four Layers of the Atmosphere
So, what is the atmosphere? It’s a very thin gaseous envelope around the Earth which is kept in place by gravitational attraction. View from near-space showing how thin our atmosphere …
How we measure cloud amounts
In meteorology, cloud cover is measured in oktas, or eighths of the sky. If you look up at the sky, and mentally divide it into eight boxes, then imagine all …
What is the difference between rain and showers?
It is easy to get confused by what we mean when we talk about rain or showers. If rain is in the forecast, we would normally expect most or all …
How are tornadoes formed?
While no two tornadoes are the same, there are certain conditions that are required for their formation. A tornado’s development can be described by a sequence of distinct phases. Stage …
Cloud in a bottle
If you try this out for yourself at home, please be careful, particularly around the potential fire risk when using the matches. We recommend you complete the experiment well away …
How clouds form
Clouds form when the invisible water vapour in the air condenses into visible water droplets or ice crystals. There is water around us all the time in the form of …
Tropical storms
In the tropics, there is a broad zone of low pressure which stretches either side of the equator. Within this area of low pressure, the air is heated over the …
Lows versus highs
We talked earlier about high and low pressure, but why do low pressure systems develop? Well let’s go back to looking at the big picture. In the six graphics below, …
Introducing weather fronts
A front is the boundary between air masses. They were named in 1919 by Bjerknes, a Norwegian meteorologist, who thought of a front as a battle ground between two opposing …
Why the sky is blue
The video explained why the sky is blue, and that it’s all to do with how the atmosphere preferentially scatters different wavelengths of light. What about when the sky is …
Circulation cells
So why don’t the poles get colder and colder, and the equator hotter and hotter? In nature, systems tend towards equilibrium, that is to say, nature doesn’t like differences, so …