In doing so, he clearly recognised the importance of what much later was to be named the Coriolis force. Between the Hadley cell and the Polar cell is the Ferrel Cell named after William Ferrel, an American meteorologist. It represents an area of cyclonic disturbances that intermittently transport heat and westerly momentum between the tropical cell and polar regions. The British Isles lie within the area of influence of the Ferrel cell. Synoptic features Low pressure regions exist at points where air rises.
High pressure occurs where air descends.
In both regions, the amounts of precipitation are rather small. The hot deserts are to be found in the region of the subtropical high, whilst the polar regions are rather dry because evaporation is rather slow and precipitation remains on the ground for some time. Define the term 'atmosphere'. Explain how photosynthesis allowed the initial release of oxygen, allowing the Earth's atmosphere to form. Arrange the following atmospheric layers into the correct order, starting with the layer, nearest the Earth's surface mesosphere, stratosphere, troposphere, thermosphere.