Presentation #206.04 in the session Investigating the Solar Chromosphere at Millimeter Wavelengths.
We present some observational constraints on the chromospheric wave heating from spectral chromospheric observations with ALMA and the IRIS spacecraft. The data from the IRIS observatory obtains UV diagnostics sampling the solar atmosphere from the photosphere through the high chromosphere to the corona while ALMA samples the chromospheric temperatures. Based on sit-and-stare UV spectral observations of the Mg II h&k spectral window we compute the velocity and intensity fluctuations in the chromosphere and find them to agree with observations of optical and millimeter diagnostics. We compare these observations with synthetic data from modern rMHD (Bifrost) models of the solar atmosphere and we find satisfactory agreement. However, when we examine the actual amount of wave energy flux in the simulated atmospheres, we find that it is not well correlated with the measured velocity or intensity oscillations. This has implications for inferring wave fluxes from observed velocities, specifically based on 1D static models. We examine more accurate ways to infer wave fluxes, specifically to be used in the future with the spectropolarimetric capabilities of DKIST.