Ross Bunn edited textbf_Methodology_At_Australian_Capital__.tex  almost 9 years ago

Commit id: 0a093a98a93fb3706b0b97c02135c6f0db6a7f50

deletions | additions      

       

\item T MUCAPE (C)  \item TD MUCAPE (C)  \end{itemize}  \textbf{Using Present Weather Reports of Thunderstorms?}  \begin{itemize}  \item Using Present Weather Reports=thunderstorms +-1 hour from sounding time, identified only 2 soundings (Melbourne 2013-03-16 1200UTC, 2013-05-31 1236UTC).  \item Analysing present weather data for all years at Melbourne Airport with the same time criteria gives \textbf{9} between 23-00UTC, \textbf{41} between 11-12UTC.   \item For Giles \textbf{37} between 23-00UTC, \textbf{117} between 11-12UTC (though no soundings at this time).  \end{itemize}  \textbf{Thoughts and Actions}  \begin{itemize}  \item \textit{What analysis can I use if Era Int doesn't identify ETS in soundings?}  \item \textit{Question - Can I use existing Era Int 850hPa Fronts dataset?}  \end{itemize}  \begin{itemize}  \item Colman 1990a implied ETS existed above very shallow surface inversions well below 850hPa, and in 1990b below ~970hPa. Browning et al 2010 observed the depth of surface inversion to 900hPa where convective initiation occurred above.   \item looks like I will need to calculate fronts dataset as low as I can go 1000? 950?. This will exclude frontal analysis in high topography regions  \item can i just use presence of surface inversion, and Tsurface (td surface) consistent with surrounding?  \end{itemize}  \textit{Question - How do I identify if a sounding lies on the cold/warm side of a front?}  \begin{itemize}  \item check surrounding stations T and TD similar to sounding station T and TD (get sounding SFC T, TD and surrounding station T, TD).  \item find closest era int front to sounding station  \item find station either side of front, T and TD difference > X ?  \item what about approaching from from west closest to station, yet station on cool side of front in east?  \end{itemize}  To identify TS and ELTS, I may use the following from Brooks et al 1994: Proximity soundings for mesocyclone environments were chosen within 160km of the observing site, and +-1 hour from the synoptic time. Soundings with CAPE <150J/kg, CIN>CAPE, EL<300mb were eliminated to account for airmass changes, outflow contamination.  Surface Based thunderstorm soundings were identified by the following criteria:  \begin{itemize}  \item Sfc CAPE > 150J/kg  \item CAPE > CIN  \item sfc CAPE > MUCAPE  \item Present Weather = thunderstorm at any time within +-1hour of sounding time  \item GPATS lightning count >0 within 160km radius of sounding site and within +-1hour of sounding time  \end{itemize}  Elevated thunderstorm soundings were identified by the following criteria:  \begin{itemize}  \item Sfc CAPE < 150J/kg  \item sfc CAPE < CIN  \item MUCAPE > MUCIN  \item sfc CAPE < MUCAPE  \item Present Weather = thunderstorm at any time within +-1hour of sounding time  \item GPATS lightning count >0 within 160km radius of sounding site and within +-1hour of sounding time  \end{itemize}