Als ik het goed begrijp gaat het bij "Convective Instability of the First Kind (CIFK)" om instabiliteit die wordt veroorzaakt doordat warmere lucht lichter is dan koude lucht en daardoor opstijgt.
Bij "Convective Instability of the Second Kind (CISK)" gaat het om instabiliteit die wordt veroorzaakt door verschillen in luchtvochtigheid:
CISK stands for Convective Instability of the Second Kind. Not only does a changing temperature profile lead to more or less instability. Instability is also influenced by the moisture profile. Instability will increase further when the dewpoint near the surface increases. The addition of moisture makes the air less dense near the surface but more importantly releases more latent heat when air rises and condenses into precipitation. Air that is less dense and is warmer due to latent heat release will produce a more significant convection. Severe thunderstorms often have an environment with warm and humid air near the surface with cool air aloft.