thunderstorms are climatical phenomena, which sometimes can cause irreparable damage to the ecology. in this study to identify any trends in the frequency of days with thunderstorms in iran, long-term statistics of 33 synoptic stations, from the beginning until 2005 was used. at first by applying nonparametric man-kendall and sen’s estimator methods on four seasonal time series, and one annua...

The purpose of this paper is to introduce electrical discharge phenomena known as transient luminous events above thunderstorms to the lightning protection community. Transient luminous events include the upward electrical discharges from thunderstorms known as starters, jets, and gigantic jets, and electrical discharges initiated in the lower ionosphere such as sprites, halos, and elves. We gi...

extended abstract 1. introduction ascent rainfall mechanism is “one of the most important factors in leading to various rainfall behaviors in different regions, such as various atmospheric precipitation seen in different time scales” (masoompour, miri, zolfaghari, & yarahmadi, 2013, p. 299). in fact, some of them can be called atmospheric phenomena due to their special nature. one of these atmo...

One of the most adverse weather phenomena in Catalonia are thunderstorms producing severe weather phenomenon like heavy rainfalls, hail storms, or tornadoes. Sometimes, these thunderstorms seem to have marked paths although in some cases these trajectories vary sharply, changing completely the movement directions that have previously followed, either breaking into several cells, or joining into...

thunderstorms are regarded not only as a significant weather event but also as a key element in water and electricity cycles of the atmosphere. generally, researchers consider the intense weather instability as a result of convection in lower levels of the atmosphere with high levels enough of humidity. usually statistic instability, the humidity of lower levels of the atmosphere and lifting me...