1. ===^====^=1^ — 1 



Table 2 



Comparison of Central-Pressure Values and Effective Resolu- 

 tion Needed to Reproduce the Central Pressure for Five 

 Analyses^ 



Analysis 



Central pressure (mb) 



Wave number 



Wavelength (km) 



Hemispheric 



940 



96 



315 



Sanders 



936 



148 



204 



00-h NGM 



946 



38 



795 



24-h NGM 



956 



46 



657 



48-h NGM 



957 



51 



592 



^ Effective resolution is defined as the minimum number of wave numbers, or equivalent 

 wavelength, at latitude 41 °N. The 24-hr and 48-hr NGM analyses are forecasts, therefore not 

 relevant to the data depiction issue (from Pauley and Bramer (1992)). 1 





930 



00 h NGM 



24 h NGM 



Hemispheric 48 h NGM 



30 60 90 120 150 180 210 240 

 Maximum Wavenumber 



Figure 2. Central sea-level pressure for the cyclone as a function of 

 reconstnjcted wave number retained as calculated from the Fourier 

 amplitudes (from Pauley and Bramer (1992)) 



necessary to reproduce the minimum surface pressure. At wave number 148, 

 the recomposed profile reproduces that of Sanders within 0.8 mb. Note that 

 the equivalent wavelengths of the hemispheric and 00-hr NGM are 315 km and 

 00-hr NGM 795 km, respectively, whereas that of Sanders' analysis is 204 km. 



Chapter 2 Operational Analysis Depictions 



