The Advection-Diffusion Equation (ADE) is solved for a constant pollutant emission from a point-like source placed
inside an unstable Atmospheric Boundary Layer (ABL). The solution is obtained adopting the novel analytical approach named
Generalized Integral Laplace Transform Technique (GILTT). The concentration solution of the equation is expressed through an
infinite series expansion. After setting a realistic scenario through the wind and diffusivity parameterizations the Ground Level
Concentration (GLC) is worked out, then an explicit approximate expression is provided for it allowing an analytic simple
expression for the position and value of the maximum. Remarks arise on the ability to express value and position of the GLC as an
explicit function of the parameters defining the ABL scenario and the source height
