Review of “The first microwave and submillimetre closure study using particle models of oriented ice hydrometeors to simulate polarimetric measurements of ice clouds” by Karina McCusker, Anthony J. Baran, Chris Westbrook, Stuart Fox, Patrick Eriksson, Richard Cotton, Julien Delanoe, and Florian Ewald.

Summary: In this study, the authors attempt to consistently simulate radiometer and radar measurements of ice particles using in situ aircraft data. Based on the in situ particle imagery, aggregates of columns and dendrites are generated at different levels of the atmosphere and used in the radiative transfer simulations, along with the particle size distributions and derived mass-size relations. The simulated brightness temperatures and polarization differences are roughly in agreement with the corresponding aircraft measurements. Simulations with the addition of oriented dendrites provided better correspondence between the simulated and observed polarization differences.

Overall, this is a very interesting study that I believe makes progress in more consistently simulating physical and radiometric properties of ice precipitation. However, there are a number of specific points in the manuscript (outlined below) that should be clarified and potentially expanded upon before it is accepted for publication.

Specific comments:

• Line 104: Please add the power for the 95 GHz radar.
• Line 155: Clarify whether this preferential alignment includes some canting/wobbling.
• Line 156: Are 3D effects like multiple scattering important in capturing the polarization differences? Please discuss or add some references here.
• Lines 172-173: Shouldn’t there be a transition between layers with predominately aggregates of columns and predominately aggregates of dendrites? Please add some brief discussion about whether this transition zone may or may not be important in the radiometer signal.
• Line 179: Please add some more details about the orientation assumptions of the particles within the aggregation model.
• Lines 213-215: It is unclear to me why the a and b parameters are being adjusted independently, with the other one being fixed. Isn’t there a set of unique a and b pairs that that give a certain IWC, subject to the PSD? Please address more thoroughly in the text why this method of determining the m-D coefficients is constrained in this way.
• Line 226: Please clarify the distribution being referred to here.
• Line 250: Please add some more details about the resolution of scattering calculations (i.e., the number of dipoles) and how many orientations were used.
• Line 276: Wouldn’t these sizes be underestimates of the true maximum dimensions given that they are derived from 2D images? Please clarify.
• Lines 309-310: How much does the aspect ratio of the aggregate impact the IMA simulations if the individual monomers are not interacting? Are the polarimetric signature more dependent on the orientations of the individual monomers? Please discuss this point briefly.
• Line 317: Based on Fig. 6b, it appears that the brightness temperatures of the simulation are on the low end of the distribution of observed brightness temperatures. There should be some additional clarification that the deepest precipitation region of the cloud where the brightness temperatures are lowest is the focus in this section.
• Line 347: Please explain why this aspect ratio was chosen.
• Lines 347-350: Why is this portion of the atmosphere replaced by dendrites? Wouldn’t dendrites be more likely above the region containing mostly aggregates? Where is the dendritic growth zone in the profile? Please address these points in this section.
• Line 380: The phrase “has a bell shape” should be replaced by something more quantitative.
• Line 431: Please describe how aspect ratio was calculated for these particles.
• Line 468: Are these particles truly column aggregates or could they be a mixture of irregular ice particles? Please discuss.

See the attached PDF file