Abstract
The possible relation between blocking-type flow patterns in the atmosphere and large-scale traveling waves has been investigated. A 30-yr time series of observational 500-hPa geopotential-height data was used to study the relation between westward-moving planetary-scale waves 1 and 2 and blocked flow. It was found that, depending on longitude, 20%–40% of blocks were related to traveling wave 1, whereas the percentage was smaller for wave 2. The study confirms results of earlier studies that suggest a possible important role for large-scale, westward-moving waves in many blocking episodes.
