Which of the following is NOT a difference between a SIGMET and a Convective SIGMET?
a) SIGMET is issued as required, while Convective SIGMET is issued hourly.
b) SIGMET is valid for 4 hours, while Convective SIGMET is valid for 2 hours.
c) SIGMET informs pilots of severe turbulence, dust/sand storms, and volcano ash, while Convective SIGMET informs pilots of tornadoes, hail, line of t'storms, embedded t'storms, surface winds 50kts or greater, and heavy precipitation affecting 40% or more of 3000 square miles.
d) SIGMET is primarily concerned with convective weather phenomena, while Convective SIGMET addresses other types of severe weather.