New paper on identification of meteorological patterns favouring African dust intrusions
A new paper entitled “Objective identification of synoptic meteorological patterns favouring African dust intrusions into the marine boundary layer of the subtropical eastern north Atlantic region”, by Alonso-Pérez et al., has been recently published in Meteorology and Atmospheric Physics.
In this study, synoptic geopotential height anomalies patterns favouring African dust outbreaks into the marine boundary layer of the subtropical Eastern North Atlantic Region were objectively identified. Also, the proportion of the total variance explained by each of these patterns was also calculated.
Dust intrusions into the marine boundary layer of the study region were identified using total suspended particles concentration data at a rural background station in Tenerife Island (El Rio station). For each African dust intrusion day in the period 1998-2003 geopotential height anomalies at 1000, 850, 700 and 500 hPa were calculated. Then, these geopotential height anomalies were grouped in monthly sets according to their proportion of the total variance explained and to their frequency of occurrence, using Principal Components and K-means statistical techniques.
Three principal geopotential height anomalies patterns were found. Type I consist on a high-pressure system over Europe that affects North Africa, occasionally giving rise to a ridge. The Canary Islands are in the southwest flank of this high-pressure system. This pattern is dominant throughout the whole year. Type II and type III patterns consist on a low located to the northeast and southeast of the Canary Islands, respectively, coupled with a high over the Mediterranean basin and/or North Africa.
In this paper two case analyses are presented, as well as a systematic validation of the meteorological pattern classification for all dust intrusions detected at ER station within the period 2004–2007.
Full reference: S. Alonso-Pérez, E. Cuevas, X. Querol, Objective identification of synoptic meteorological patterns favouring African dust intrusions into the marine boundary layer of the subtropical eastern north Atlantic region. Meteorology and Atmospheric Physics, doi 10.1007/s00703-011-0150-z. Accepted: 23-June-2011.
Abstract and paper (pdf), here.