Hotfix: Get Met_AREAM2 from GCHP StateMet for mass tables

gcpy/benchmark/run_benchmark.py
- For GCHP vs GCC mass tables:
  - Define a new variable "area_m2_file", which contains the path
    to the StateMet collection for GCHP (Dev)
  - Pass "area_m2_file" to make_benchmark_mass_tables via the
    "dev_met_extra" keyword
- For GCHP vs. GCHP mass tables
  - Define a new variable "area_m2_file", which contains the path
    to the StateMet collection for the GCHP Dev output
  - Pass "area_m2_file" to make_benchmark_mass_tables via the
    "ref_met_extra" and "dev_met_extra" keywords

gcpy/units.py
- In convert_units.py
  - If the area variable is on the GCHP diagnostic grid, but the
    input data is on the GCHP checkpoint grid, call reshape_MAPL_CS
    to reshape the area to the GCHP checkpoint grid.  This will
    prevent a broadcast error caused by differently shaped arrays.

Signed-off-by: Bob Yantosca <yantosca@seas.harvard.edu>

Author: yantosca

CHANGELOG.md

@@ -59,6 +59,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Updated `make_benchmark_mass_tables` and `create_global_mass_table` to allow Ref and Dev to have different dates if so chosen
 - Updated `run_benchmark.py` to generate mass tables at start and end of the simulation
 - Updated `run_1yr_fullchem_benchmark.py` and `run_1yr_tt_benchmark.py` to generate mass tables at the 1st day of each month from Jan 2019 thru Jan 2020
+- Updated `run_benchmark.py` to take the `Met_AREAM2` field from the GCHP `StateMet` collection when computing mass tables for 1hr/1mon benchmarks
+- Updated routine `convert_units` to reshape the area variable tomatch input data on the GCHP checkpoint grid
 
 ### Fixed
 - Fixed grid area calculation scripts of `grid_area` in `gcpy/gcpy/cstools.py`

gcpy/benchmark/run_benchmark.py

@@ -1222,6 +1222,15 @@ def run_benchmark_default(config):
         if config["options"]["outputs"]["mass_table"]:
             print("\n%%% Creating GCHP vs. GCC global mass tables %%%")
 
+            # Kludge, take the Met_AREAM2 variable at the end of the
+            # month from the StateMet collection for GCHP (Dev)
+            area_m2_file = get_filepath(
+                gchp_vs_gchp_devdir,
+                "StateMet",
+                gchp_end_dev_date,
+                is_gchp=True
+            )
+
             # Filepaths and date strings for start of run
             ref = get_filepath(
                 gchp_vs_gcc_refrstdir,
@@ -1257,6 +1266,7 @@ def run_benchmark_default(config):
                 ref_hdr_label=f"at {ref_date_str}",
                 dev_hdr_label=f"at {dev_date_str}",
                 subdst=dev_date_str,
+                dev_met_extra=area_m2_file,
             )
 
             # Filepaths and date strings for end of run
@@ -1294,6 +1304,7 @@ def run_benchmark_default(config):
                 ref_hdr_label=f"at {ref_date_str}",
                 dev_hdr_label=f"at {dev_date_str}",
                 subdst=dev_date_str,
+                dev_met_extra=area_m2_file,
             )
 
         # ==================================================================
@@ -1849,6 +1860,15 @@ def run_benchmark_default(config):
         if config["options"]["outputs"]["mass_table"]:
             print("\n%%% Creating GCHP vs. GCHP global mass tables %%%")
 
+            # Kludge, take the Met_AREAM2 variable at the end of the
+            # month from the StateMet collection for Dev
+            area_m2_file = get_filepath(
+                gchp_vs_gchp_devdir,
+                "StateMet",
+                gchp_end_dev_date,
+                is_gchp=True
+            )
+
             # Filepaths and date strings for start of run
             ref = get_filepath(
                 gchp_vs_gchp_refrstdir,
@@ -1887,6 +1907,8 @@ def run_benchmark_default(config):
                 ref_hdr_label=f"at {ref_date_str}",
                 dev_hdr_label=f"at {dev_date_str}",
                 subdst=dev_date_str,
+                ref_met_extra=area_m2_file,
+                dev_met_extra=area_m2_file,
             )
 
             # Filepaths and date string for end of run
@@ -1927,6 +1949,8 @@ def run_benchmark_default(config):
                 ref_hdr_label=f"at {ref_date_str}",
                 dev_hdr_label=f"at {dev_date_str}",
                 subdst=dev_date_str,
+                ref_met_extra=area_m2_file,
+                dev_met_extra=area_m2_file,
             )
 
         # ==================================================================

gcpy/units.py

@@ -7,7 +7,8 @@
 import numpy as np
 import xarray as xr
 import gcpy.constants as physconsts
-
+from gcpy.cstools import is_cubed_sphere_diag_grid, is_cubed_sphere_rst_grid
+from gcpy.util import reshape_MAPL_CS
 
 def adjust_units(units):
     """
@@ -197,6 +198,13 @@ def convert_units(
         moles_C_per_mole_species = species_properties.get("MolecRatio")
     else:
         moles_C_per_mole_species = 1.0
+        
+    # EDGE CASE: For GCHP vs GCHP mass tables, we often need to multiply
+    # data taken from a GCHP checkpoint file by the surface area taken 
+    # from the StateMet History file.  If this is the case, then reshape
+    # the area array to the GCHP checkpoint grid before multiplication.
+    if is_cubed_sphere_rst_grid(dr) and is_cubed_sphere_diag_grid(area_m2):
+        area_m2 = reshape_MAPL_CS(area_m2)
 
     # ==============================
     # Compute conversion factors