This image presents three choropleth maps of California, visualizing data on respiratory/cardiovascular patient percentages, bad PM level days, and AQI levels by county from 2010 to 2023.

The first map, in shades of red, highlights counties with a higher percentage of respiratory and cardiovascular patients, indicating a strong health burden in central and southern regions. The second map, in purple, shows the average number of bad PM (particulate matter) level days, with darker regions suggesting higher pollution exposure, particularly in northern and central California. The third map, in shades of blue, illustrates the average AQI (Air Quality Index) levels, where darker areas represent worse air quality, aligning with regions that have high pollution levels.

A clear correlation appears between high AQI, bad PM level days, and respiratory/cardiovascular health issues, suggesting that poor air quality could contribute to health problems.

Central Valley and urban areas show the most significant impact across all three metrics, likely due to industrial activity, traffic emissions, and geographical factors. This visualization effectively communicates the environmental and public health challenges faced by different counties in California.

Before taking a look at the coloring and sizing of these scatterplots, there is a positive relationship between the median AQI level and the number of respiratory cases. When there is a higher AQI, there tends to be more respiratory cases in a county. Although these graphs do not exhibit perfect positive relationships with race, medical coverage, and respiratory cases, there are still important insights to gain.

The left chart colors and sizes counties by the percentage of non-white residents; large and dark purple circles represent a high population of non-white residents. Majority of the larger and darker purple circles also exhibit higher median AQI levels; Imperial, Kings, Madera, and Los Angeles all have AQI levels from 60 to 79. These areas with higher minority populations and higher median AQI levels seem to experience worse respiratory health outcomes, shown in higher average respiratory cases in that county. In contrast, many of the small and light purple circles, representing a low population of non-white residents, exhibit lower AQI levels and respiratory cases; Humboldt, Lake, and Del Norte, for example, all have AQI levels below 36 and face fewer average respiratory cases.

The right chart colors and sizes counties by the percentage of residents on MediCal: large and dark green circles represent a high population of MediCal residents. Majority of the smaller and light green circles with fewer Medical residents exhibit lower AQI median levels and fewer respiratory cases. While the large and dark green circles are more dispersed in this graph, the counties with the highest respiratory cases and AQI levels tend to be darker. The darkest green and largest circle, with the highest percentage of MediCal residents, is Madera and has the largest average amount of respiratory cases and a relatively large AQI of 60.92 compared to the other counties.

The correlation between high AQI levels, respiratory illness, and the percentage of non-white and low-income residents suggests a potential relationship in which marginalized populations may experience disproportionate exposure to air pollution.