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CATEGORIES:AI4ER Seminar Series
SUMMARY:Using ensemble meteorological datasets to overcome
  limitations in a Bayesian volcanic ash inverse mo
 delling system - Helen Webster | Met Office
DTSTART;TZID=Europe/London:20210209T110000
DTEND;TZID=Europe/London:20210209T123000
UID:TALK155386AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/155386
DESCRIPTION:Volcanic ash in the atmosphere poses a significant
  hazard to aviation. To minimise risk\, atmospheri
 c dispersion models are used to predict the transp
 ort of ash clouds. Accurate ash cloud forecasts re
 quire a good estimate of mass eruption rates and a
 sh injection heights. These parameters are\, howev
 er\, highly uncertain and inversion techniques hav
 e been developed to better constrain the emission 
 source term and improve ash cloud forecasts.\nInTE
 M for volcanic ash is a Bayesian inversion method 
 which gives a best estimate of height- and time-va
 rying ash emission rates. It combines satellite ob
 servations of the ash cloud\, prior estimates of t
 he ash emissions and an atmospheric dispersion mod
 el. Uncertainties in the atmospheric dispersion mo
 del\, including uncertainty in the driving meteoro
 logical data\, are not currently represented and t
 his limits the success of the method when such err
 ors are significant.\nDiscrepancies between modell
 ed and observed ash clouds from the 2011 eruption 
 of the Icelandic volcano Grímsvötn were previously
  attributed to errors in the input meteorological 
 data. We use this eruption as a case study to inve
 stigate using an ensemble of numerical weather pre
 diction forecasts to improve ash cloud forecasts b
 y accounting for meteorological errors in InTEM. A
 n iterative method is employed to identify the bes
 t meteorological dataset. We explore if improvemen
 ts are seen and how this method might be implement
 ed in an operational context.\n\n\nJoin Zoom Meeti
 ng\nhttps://zoom.us/j/6708259482?pwd=Qk03U3hxZWNJZ
 UZpT2pVZnFtU2RRUT09\n\nMeeting ID: 670 825 9482\nP
 asscode: 9fkTAc
LOCATION:https://zoom.us/j/6708259482?pwd=Qk03U3hxZWNJZUZpT
 2pVZnFtU2RRUT09
CONTACT:Tudor Suciu
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