British Sign Language Glossaries of Curriculum Terms

BSL Environmental Science Glossary - Negative NAO Phase definition

Description: Negative NAO phase occurs when atmospheric pressure in the Azores High is lower than normal and the Icelandic Low remains normal. This results in a weakened pressure difference between these two points. Winds moving from West to East become weaker and the Jet Steam shifts south bringing very cold and dry air from the East e.g. Siberia and Northern Europe. This phase also brings cold, snowy weather from the Arctic known as 'Easterly Weather'. In the UK temperatures are then colder, there is more chance of snow, fewer storms and drier weather, but occasional heavy snowfall. Climate Change is affecting weather systems by melting Arctic ice and reducing the temperature difference between these two weather systems making it increasingly difficult to predict weather patterns.