# README file for "Using satellite observations to evaluate model microphysical representation of Arctic mixed-phase clouds" by Shaw et al. in review at Geophysical Research Letters

#### Jonah Shaw, 2021/12/15

This file describes the organization and data included in this repository. Data is stored in three .zip files. 
modelfields_present.zip includes selected CAM6 model output fields from present-day simulations
modelfields_+4K.zip includes selected CAM6 model output fields from +4K simulations
cloudfeedback.zip includes calculated cloud feedback parameters using Soden et al. (2008) radiative feedback kernels

Within each .zip file are individual netcdf files for each model variant presented in Shaw et al.. These files follow the naming conventions used in that manuscript. Model output fields in modelfields_present.zip and modelfields_+4K.zip retain units and variable descriptions from CAM6. A full description of all CAM6 output fields can be found here (https://www.cesm.ucar.edu/models/cesm2/atmosphere/docs/ug6/hist_flds_f2000.html). The model output fields found in these files fall into three main categories:

1. Supercooled Liquid Fraction (SLF) fields (SLFXCLD_ISOTM, CT_SLFXCLD_ISOTM, CLD_ISOTM, CT_CLD_ISOTM). These fields have dimensions of time, latitude, longitude, and isotherm. During model computation SLF is weighted by cloud amount at each isotherm, requiring a normalization step when computing SLF. As such, the cloud-bulk SLF is computed as SLF = SLFXCLD_ISOTM / CLD_ISOTM and cloud-top SLF is computed as CT_SLF = CT_SLFXCLD_ISOTM / CT_CLD_ISOTM. These fields are used in Figure 1, Figure 4(d), and Figure S5.

2. Cloud Fields from the CALIOP satellite simulator within COSP2. We include all 2D COSP-simulated CALIOP output fields. Only total cloud, total liquid cloud, total ice cloud, total phase-unidentified cloud, and low-level liquid cloud variables are used in Shaw et al.. All fields include units and variable descriptions standard to CAM6 output. These fields are used in Figure 2, Figure 3, Figure 4 panels b and c, Figure S2, Figure S3, Figure S4, and Table S1.

3. Radiation fields (LWCF, SWCF, FLDS, FSDS). These fields are compared with CERES-EBAF observations and presented in Figure 3 and Table S1.

4. Ice crystal properties (AREI, AWNI, FREQI). These fields are used to evaluate the size and concentration of cloud ice crystals in model simulations (Table1 ). Both average crystal radius (AREI) and ice crystal concentrations (AWNI) must be normalized to ice cloud frequency in order to compute appropriate values.

Cloud feedback fields (cloudfeedback.zip) are computed using cloud radiative kernels from Soden et al. (2008). We make use of these kernels in Figure 4(a,c,d) and Figure S4. We use the short- and longwave adjusted cloud feedbacks (fb_adj_cloud_sw, fb_adj_cloud_lw). Feedback values in these files are NOT normalized to surface temperature change. Instead, temperature change must be computed from model surface temperature (TS) fields included in the model output files.