Analysis of global Terrestrial Gamma Ray Flashes distribution and special focus on AGILE detections over

Global distribution of the Terrestrial Gamma-ray Flashes (TGFs) detected by AGILE and RHESSI for the period from March 2009 to July 2012 has been analysed. A fourth TGF production region has been distinguished over the Pacic. It is conrmed that TGF occurrence follows the Intertropical Convergence Zone(ITCZ) seasonal migration and prefers afternoons. TGF/lightning ratio appears to be lower over America than other regions suggesting that meteorological regional dierences are important for the TGF production. Diurnal cycle of TGFs peaks in the afternoon suggesting that Convective Available Potential Energy (CAPE) and convection are important for TGF production. Moreover all AGILE passages over South America in the same period have been analysed to nd meteorological preferences for TGF occurrence. In each passage the analysis of Cloud Top Altitude (CTA), CAPE,