Add George's original recipe for sea level seasonal pressure

Author: George Pulickan

docs/source/recipes/plot_19_recipe.py

@@ -0,0 +1,70 @@
+import cfplot as cfp
+import cf
+import numpy as np
+import pandas as pd
+from datetime import timedelta
+import matplotlib.pyplot as plt
+
+# 1. Load the dataset
+file_path = "~/Documents/Datasets/ERA5_monthly_averaged_SST.nc"
+f = cf.read(file_path)
+sst = f[0]  # Select the SST variable
+
+# Collapse data by area mean (average over spatial dimensions)
+am = sst.collapse("area: mean")  # equivalent to "X Y: mean"
+am.squeeze(inplace=True)
+
+# Check available coordinates (already found 'dimensioncoordinate0' as the time coordinate)
+print("Available coordinates:", am.coordinates())
+
+am_data_key = am.coordinate("dimensioncoordinate0", key=True)
+am_copy = am.copy().subspace(**{am_data_key: cf.mam()})
+print(am_copy)
+exit()
+# Retrieve the time coordinate using its internal identifier
+am_data = am.coordinate("dimensioncoordinate0")
+am_data_copy = am_copy.coordinate("dimensioncoordinate0")
+# Convert the time data from 'hours since 1900-01-01' to datetime format
+#time_units = time_coord.units
+#am_time = time_coord.data
+#am_time_datetime = am.subspace(T=cf.dt("2022-12-01 00:00:00"))
+
+# Convert datetime to numeric values for plotting (e.g., using matplotlib date format)
+#am_time_numeric = pd.to_numeric(pd.to_datetime(am_time_datetime))
+
+# Extract data and replace missing values
+#am_data = am.data
+#am_data = np.where(am_data == -32767, np.nan, am_data)
+
+# Create the line plot using the full dataset with numeric x-axis
+
+
+print(am[:10])
+print(am_data[:10].data.datetime_as_string)
+
+cfp.gopen(file="Recipe3.png")  # Start the plot
+cfp.lineplot(
+    x=am_data,
+    y=am,
+    color="blue",
+    title="Global Average Sea Surface Temperature",
+    ylabel="Temperature (K)",
+    xlabel="Time"
+)
+
+cfp.lineplot(
+    x=am_data_copy,
+    y=am_copy,
+    color="red",
+)
+cfp.gclose()  # Finish the plot
+
+
+# Save the plot to a file using matplotlib
+plt.savefig("global_avg_sst_plot.png")
+
+# Show the plot interactively
+plt.show()
+
+print("Plot created and saved successfully.")
+