Cluster analysis of five years of back trajectories arriving in Athens, Greece
Φόρτωση...
Ημερομηνία
Συγγραφείς
Markou, M. T.
Kassomenos, P.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Atmospheric Research
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Cluster analysis was applied to back trajectories reaching the Greater Athens area Greece The database contains five years of four-day kinematic back trajectories arriving at three heights 750 m 1500 m and 3000 m above mean sea level computed with version 4 7 of the Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT) In this study the analysis consists of two steps The first step Involves the clustering of trajectories at each height level and the separation of the retained clusters based on the length of their centroids (cluster-mean trajectories) using the Haversine formula In order to obtain this separation three categories of back trajectories are defined based on the above mentioned length short-slow-moving (SSM) with length up to 1500 m medium-moving (MM) with length from 1500 m to 3000 m and long-fast-moving (LFM) with over 3000 m Cluster analysis was applied again on each of these three categories of back trajectories at each of the above heights (second step) The results show that as height increases the number of back trajectories in the SSM/LFM categories decreases/increases due to the weaker influence of the ground and the stronger winds In addition airflows categorized in SSM come almost from all points of the compass in contrast to the MM and LFM categories where the flows originate mostly from the west and north sectors Specifically at 750 m the north sector prevails for all categories at 1500 m the north sector dominates for SSM and LFM while for MM the west sector dominates The situation is different at 3000 m where domination of the south sector for SSM and of the west sector for MM and LFM is observed Moreover patterns of local circulation with very short trajectories are observed in all heights presenting a seasonal distribution with higher frequency of occurrence at 750 m and 1500 m in the winter and at 3000 m in the summer (C) 2010 Elsevier B V All rights reserved
Περιγραφή
Λέξεις-κλειδιά
back trajectories, cluster analysis, haversine formula, athens, greece, long-range transport, synoptic meteorological controls, precipitation chemistry, air, accuracy, tracers, model, area
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000284983400027
http://ac.els-cdn.com/S0169809510002000/1-s2.0-S0169809510002000-main.pdf?_tid=787b0a2338db0a120b2fab2dbc48d2a2&acdnat=1334228038_aa8269f0036678dae6ebbe6af789b3d6
http://ac.els-cdn.com/S0169809510002000/1-s2.0-S0169809510002000-main.pdf?_tid=787b0a2338db0a120b2fab2dbc48d2a2&acdnat=1334228038_aa8269f0036678dae6ebbe6af789b3d6
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών και Τεχνολογιών. Τμήμα Βιολογικών Εφαρμογών και Τεχνολογιών