Evaluating indices of mid latitude circulation

Synoptic climatology attempts to explain variations in meteorological elements with reference to large scale circulation patterns. A common parameter used to represent the strength of mid latitude circulation is the zonal index. High zonal index numbers represent vigorous westerly flow and are refle...

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Bibliographic Details
Main Author: Spellman, G.
Format: Article in Journal/Newspaper
Language:English
Published: 1997
Subjects:
Online Access:https://pure.northampton.ac.uk/en/publications/95e67c6d-94c2-4817-aa24-899604a19182
http://www.scopus.com/inward/record.url?eid=2-s2.0-0031394166&partnerID=MN8TOARS
Description
Summary:Synoptic climatology attempts to explain variations in meteorological elements with reference to large scale circulation patterns. A common parameter used to represent the strength of mid latitude circulation is the zonal index. High zonal index numbers represent vigorous westerly flow and are reflected in above average precipitation, above average winter temperatures and below average summer temperatures in the British Isles. Low index numbers represent meridional flow resulting in dry conditions, warm summers and cold winters. This study examines the performance of a zonal index for the area 35°N-55°N and 30°W-10 ° E in accounting for seasonal variations in the England and Wales precipitation series and the Central England temperature series. Results are contrasted with the simpler North Atlantic Oscillation Index - another parameter for describing mid latitude circulation.