fix assignments and add attributes

pydropsonde/circles.py

@@ -29,8 +29,18 @@ def get_div_and_vor(self):
         D = self.circle_ds.dudx + self.circle_ds.dvdy
         vor = self.circle_ds.dvdx - self.circle_ds.dudy
 
+        vor_attrs = {
+            "standard_name": "atmosphere_relative_vorticity",
+            "long_name": "Area-averaged horizontal relative vorticity",
+            "units": str(1 / units.second),
+        }
+        D_attrs = {
+            "standard_name": "divergence_of_wind",
+            "long_name": "Area-averaged horizontal mass divergence",
+            "units": str(1 / units.second),
+        }
         self.circle_ds = self.circle_ds.assign(
-            dict(div=(["alt"], D.values), vor=(["alt"], vor.values))
+            dict(D=(["alt"], D.values, D_attrs), vor=(["alt"], vor.values, vor_attrs))
         )
         return self
 
@@ -43,20 +53,26 @@ def get_density(self, sonde_dim="sonde_id"):
             self.circle_ds.ta.values * units.kelvin,
             mr,
         )
-        self.circle_ds = self.circle_ds.assign(
-            dict(density=(self.circle_ds.ta.dims, density.magnitude))
-        )
-        self.circle_ds["density"].attrs = {
-            "standard_name": "density",
+        density_attrs = {
+            "standard_name": "air_density",
+            "long_name": "Air density",
             "units": str(density.units),
         }
-        self.circle_ds = self.circle_ds.assign(
-            dict(mean_density=self.circle_ds["density"].mean(sonde_dim))
-        )
-        self.circle_ds["mean_density"].attrs = {
-            "standard_name": "mean density",
+        mean_density_attrs = {
+            "standard_name": "mean_air_density",
+            "long_name": "Mean air density in circle",
             "units": str(density.units),
         }
+        self.circle_ds = self.circle_ds.assign(
+            dict(
+                density=(self.circle_ds.ta.dims, density.magnitude, density_attrs),
+                mean_density=(
+                    ["alt"],
+                    self.circle_ds.density.mean(sonde_dim),
+                    mean_density_attrs,
+                ),
+            )
+        )
 
         return self
 
@@ -72,24 +88,38 @@ def get_vertical_velocity(self):
         del_w = -div * height_diff.values
 
         w_vel = del_w.cumsum(dim="alt")
-        self.circle_ds = self.circle_ds.assign(dict(w_vel=w_vel))
-        self.circle_ds["w_vel"].attrs = {
-            "standard name": "vertical velocity",
+        w_vel_attrs = {
+            "standard_name": "upward_air_velocity",
+            "long_name": "Area-averaged vertical air velocity",
             "units": str(units.meter / units.second),
         }
+        self.circle_ds = self.circle_ds.assign(
+            w_vel=(["alt"], w_vel.values, w_vel_attrs)
+        )
 
         return self
 
     def get_omega(self):
-        p_vel = (
-            -self.circle_ds.mean_density.values
-            * units(self.circle_ds.mean_density.attrs["units"])
-            * self.circle_ds.w_vel.values
-            * units(self.circle_ds.w_vel.attrs["units"])
-            * mpconst.earth_gravity
+        # Ensure density and vertical velocity are properly aligned and use correct units
+        rho = self.circle_ds.mean_density * units(
+            self.circle_ds.mean_density.attrs["units"]
         )
+        w = self.circle_ds.w_vel * units(self.circle_ds.w_vel.attrs["units"])
+
+        # Calculate omega using the correct formula: omega = - rho * g * w
+        g = mpconst.earth_gravity  # gravitational constant (metpy constant)
+
+        # Compute omega (vertical pressure velocity)
+        p_vel = -(rho * g * w)
+
+        # Assign omega to the dataset with correct attributes
+        omega_attrs = {
+            "standard_name": "atmosphere_vertical_velocity",
+            "long_name": "Area-averaged atmospheric pressure velocity",
+            "units": str(p_vel.units),
+        }
         self.circle_ds = self.circle_ds.assign(
-            dict(omega=(self.circle_ds.w_vel.dims, p_vel.magnitude))
+            omega=(self.circle_ds.w_vel.dims, p_vel.magnitude, omega_attrs)
         )
 
         return self