Preprocess California ozone measurements from EPA Air Quality Portal

download-ca-2020-ozone.py

import pandas as pd

# Run this as a notebook so that the bash cell magic ! works
import pandas as pd

! wget https://aqs.epa.gov/aqsweb/airdata/daily_44201_2020.zip
    
filepath = './daily_44201_2020.csv'
df = pd.read_csv(filepath)

state_code = 6
subset_df  = df[df['State Code']==state_code]
subset_df['timestamp'] = pd.DatetimeIndex(subset_df['Date Local'])
subset_df['lat_long']  = subset_df['Latitude'].astype(str) + '/' + subset_df['Longitude'].astype(str)

pivot_df = pd.pivot_table(subset_df[['lat_long', 'Arithmetic Mean','Date Local']],
               values='Arithmetic Mean',
               index='lat_long', columns='Date Local').T

no_missing = pivot_df.iloc[0:150].dropna(how='any', axis=1)

no_missing.to_csv('./california_ozone_2020.csv')