1. Weather: air masses and fronts
The weather we experience at the surface of the Earth is a product of patterns of air movement in the Earth's atmosphere.
The atmosphere is not static; instead, air is in constant motion, driven, for example, by the sun's energy warming land masses.
Warm air rises, cool air sinks. This means there are vertical flows of air. The air will have different temperatures and densities in different regions of the globe, and these 'air masses' behave differently. At the boundary of air masses, weather fronts may form.
This section covers air masses and weather fronts.
Before going further, let's start by taking a look at today's weather.
The weather where you are
First, observe the weather where you are. Step outside or put your head out of the window. What is the weather like? Consider the following:
Here are some aspects of weather to think further about:
The weather at an ECN site
Now, let's look at some real-time weather data collected at ECN Rothamsted in Hertfordshire.
These data are measured using accurate sensors on an Automatic Weather Station like the one shown in the photo (in the background you can also see a white box - a Stevenson Screen - which contains manually-read weather instruments).
More about weather at ECN sites
You might find these news items on our website interesting:
* Source: Rothamsted Research Ltd