Mariposa, California Air Quality

Mariposa County, California (CA)

↓ Improvingover 10 years

Air Quality Grade

51/100

Current Median AQI

Good

5-Year Avg AQI

-6

10-Year Change

Better

Unhealthy Days/yr

5-year average

Ozone

Primary Pollutant

Ground-Level Ozone

10-Year AQI Trend

The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days). This area has seen measurable air quality improvement over the decade.

Air Quality Day Breakdown

Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).

Year-by-Year Data

Year	Median AQI	90th Pct	Max AQI	Good Days	Moderate	Unhealthy+	Pollutant
2023	47	77	264	217	131	17	Ozone
2022	48	89	198	211	125	29	Ozone
2021	49	97	162	193	140	32	Ozone
2020	49	111	1073	195	123	48	Ozone
2019	50	84	185	192	159	14	Ozone
2018	53	108	352	156	169	40	Ozone
2017	54	101	189	146	179	40	Ozone
2016	48	93	159	197	149	20	Ozone
2015	47	84	240	220	134	11	Ozone
2014	53	93	153	160	178	27	Ozone

What This Means for Mariposa County Residents

Mariposa, California has received an Air Quality Grade of C (51/100) based on a decade of EPA monitoring data. The current median AQI of 47 falls in the "Good" range.

Encouragingly, air quality here has been improving, with the median AQI dropping by 6 points over the monitoring period. This trend suggests continued investment in emission controls and cleaner energy.

The primary pollutant affecting this area is Ground-Level Ozone. Over the past 5 years, this area has averaged 28 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.