Understanding the volcanic impact on stratospheric water vapour and the hydrological cycle

In total volcanic eruptions lead to a cooling of the earth’s surface due to scattering of solar radiation back to space. However the concentration of the greenhouse gas water vapour in the stratosphere also increases in consequence of the eruption event and the presence of volcanic aerosols in the lower stratosphere. The increased stratospheric water vapour concentrations counteract the general cooling and potentially lead to a slight positive forcing after the aerosols have fallen out. Additionally stratospheric chemistry is impacted by the increased humidity content in the otherwise relatively dry stratosphere.

I am investigating the changes in stratospheric water vapour after volcanic eruptions using a suite of volcanically perturbed 100-member-ensemble simulations of the coupled climate model MPI-ESM1.2-LR. Topics I am interested in include the detection threshold, the predictability of the response, as well as the actual radiative impact of the stratospheric water vapour attributable to the influence of volcanic eruptions.