Strong ill-posedness in W1,? of the 2d stably stratified Boussinesq equations and application to the 3d axisymmetric Euler Equations.
We prove the strong ill-posedness of the two-dimensional Boussinesq system in vorticity form in L8pR2q
without boundary, building upon the method that Shikh Khalil & Elgindi arXiv:2207.04556v1 developed for scalar
equations. We provide examples of initial data with vorticity and density gradient of small L8pR2q size, for which the
horizontal density gradient has a strong L8pR2q-norm inflation in infinitesimal time, while the vorticity and the vertical
density gradient remain bounded.






