deletions | additions       diff --git a/The Global Position and Tracking System.tex b/The Global Position and Tracking System.tex  index d729066..adeb9d7 100644  --- a/The Global Position and Tracking System.tex  +++ b/The Global Position and Tracking System.tex 
...
GPATS CG, GC IC stroke data of date, time, latitude, longitude and peak current values in kilo-amps is available from 1998-2014, with positive peak current values denoting positive ground strokes (CG or GC strokes), and negative values denoting negative ground strokes (CG or GC strokes). Strokes with peak current values of 0.0 denote IC stokes. Kuleshov (2012) however identified GPATS negative stroke peak currents prior to 2007 erroneously reported as positive peak currents. GPATS negative and positive ground stroke numbers for 2007 and 2008 were comparable to CGR4 positive and negative strokes for those years, with the suggestion of processing changes in January 2007 corrected false recording of negative ground strokes as positive. A GPATS dataset from 2008-2014 was deemed sufficient to create a climatology of elevated thunderstorms.  Dowdy & Kuleshov (2014) developed an Australian ground stroke density map (number of strokes per kilometre per year), based on high-quality research lightning flash counter data (CGR4) and detected lightning from the TRMM polar orbiting satellite’s Lightning Image Sensor (LIS) over the period 1995-2002.    High values of GPATS ground stroke densities over 2008-2014 (Figure 1) compare well to Figure 1 (Dowdy & Kuleshov 2014), giving broad confidence in the spatial accuracy of GPATS. However a dearth of GPATS strokes in south-west Western Australia not seen in Figure 1 (Dowdy & Kuleshov 2014) is most likely due to a lack of GPATS ground sensors in that region. Also differing observation periods between the two plots could account for differing highest density values (GPATS: 17 strokes per km per yr, Figure 1: 12 strokes per km per yr).  \textbf{para re GPATS density plot and CG/km/yr creation}  \begin{itemize}  \item Australian ground stroke density plots exist (Dowdy & Kuleshov 2014), derived from Lightning Flash Counter and TRMM LIS estimated ground stroke FLASH densities from total lightning FLASH densities (using Z = cloud/ground = 2 +-30\% from Kuleshov (2006) emperical fraction of total to ground lightning flashes for Australia, Ng = Nt/(Z+1). Others have used this ratio to estimate number of ground strokes from TRMM (Given TRMM gives total lightning).