  Observational searches for large-scale vorticity modes in the late time
Universe are underexplored. Within the standard $\Lambda$CDM model, this is
well motivated given the observed properties of the cosmic microwave background
(CMB). However, this means that searches for cosmic vorticity modes can serve
as a powerful consistency test of our cosmological model. We show that through
combining CMB measurements of the kinetic Sunyaev-Zel'dovich and the moving
lens effects with galaxy survey data we can constrain vorticity fields
independently from the large scale cosmic velocity field. This approach can
provide stringent constraints on the largest scale modes and can be achieved by
a simple change in the standard estimators. Alternatively if one assumes there
are no cosmic vorticity modes, this estimator can be used to test for
systematic biases in existing analyses of kinetic Sunyaev-Zel'dovich effect in
a manner analogous to curl-lensing.
