Jan, If it adds a significant delta angular momentum push, it would probably be detectable. Krakatoa was the formation of an island in a narrow strait which would impact the oceanic flow east-to-west and west-to-east
Discussed this aspect here: http://contextearth.com/2018/05/08/unified-enso-proxy/#comment-208496
On 12/22/2018, a killer tsunami related to Krakatoa hit this same Sunda Strait region depicted above. It may again transiently impact the flow hydrodynamics as the original Krakatoa eruption did.