matplotlib aqi colorscale

epacolors.py

def get_epacmapnorm(spc, freq):
    """
    Arguments
    ---------
    spc : str
        choices 'pm25' or 'o3'
    freq : str
        choices '1h', '24h' (pm-only), '8h' (o3-only), 'mda8' (o3-only)

    Returns
    -------
    cmap, norm : matplotlib.colormaps.Colormap, matplotlib.colors.BoundaryNorm

    Notes
    -----
    Colors for 24h and 8h are EPA AQI. For 1h, the colors are consistent with EPA's airnowtech
    AQI colors and cutpoints are consistent with EPA-454/B-24-002 May 2024
    """
    import matplotlib.colors as mc
    aqicolors = ['#00e300', '#fefe00', '#fe7e00', '#fe0000', '#8e3f96', '#7e0023']
    pm1hcolors = [
        '#009500', '#98cb00', '#fefe98', '#fefe00',
        '#fecb00', '#f69800', '#fe0000', '#d50092'
    ]  # 8 colors between 9 edges
    pm1hedges = [-5, 10, 20, 30, 50, 70, 90, 120, 1000]
    # pm24hedges = [0, 12, 35.5, 55.5, 150.5, 250.5, 255]  # old pm25 aqi cutpoints EPA 454/B-18-007 September 2018
    pm24hedges = [0, 9, 35.5, 55.5, 125.5, 225.5, 255]  # new pm25 aqi cutpoints EPA-454/B-24-002 May 2024

    o31hcolors = [
        '#00fe00', '#fefe80', '#fefe00', '#fbbe43', '#fe8000', '#fe0000'
    ]  # 6 colors beteen 7 edges for airnowtech 1h
    o31hedges = [0, 60, 80, 100, 112, 125, 1000]  # airnowtech 1h cuts
    o3mda8edges = [0, 54, 70, 85, 105, 200, 255]  # ozone ppb aqi cutpoints EPA-454/B-24-002 May 2024
    levels, colors = {
        ('pm25', '1h'): (pm1hedges, pm1hcolors),
        ('pm25', '24h'): (pm24hedges, aqicolors),
        ('o3', '1h'): (o31hedges, o31hcolors),
        ('o3', '8h'): (o3mda8edges, aqicolors),
        ('o3', 'mda8'): (o3mda8edges, aqicolors),
    }[spc, freq]
    return mc.from_levels_and_colors(levels, colors)