Using Wind Data to Predict the Risk of Volcanic Eruption: An Example from Damavand Volcano, Iran

Damavand volcano is located 60 km to the east north- east of tehran. it is a dormant stratovolcano outcrop in the alborzmountains of northern iran and is the highest mountain (5670 m) in the middle east and west asia. mazandaran province, one of themost populous provinces by population density, semnan and gorgan provinces further east are neighbours of the damavand.volcanism in damavand goes back to at least 1 ma year ago and the latest eruption occurred 7000 years ago. tephra dispersal involcanoes strongly depends on atmospheric information in particular wind direction and velocity in stratospheric and troposphericlevels. we present an analysis of wind data to assess the hazards that would result from tephra fall in the cities and provincesneighbouring damavand. atmospheric data were provided from the meteorological stations at mehr-abaad airport, wyominguniversity and global data sets. we examine wind data from 17 standard pressure levels which cover from 5700 meter (damavandpeak) to 31 km above sea level. if damavand moved into a state of unrest then a major explosive eruption is a plausible scenario thatshould be planned for. the results confirm that the area to the south and east of volcano will be affected by tephra. communitiesaround the southern and eastern flanks of the volcano also have high hazard. wind data also shows the effects of season on dispersalof tephra from a 25 km high eruption column. tephra dispersal is dominantly towards the east in all seasons for eruption columns upto 20 km above sea level. mazandran, semnan and gorgan providence could be affected in this case. at 25 km- high eruptioncolumn and during the summer there are easterly winds; therefore, the tephra would disperse toward the east. in this case tehrancould experience a tephra fall deposit