Santa Barbara County, California air quality history
Daily Air Quality Index summaries from EPA monitors in Santa Barbara, California, 1980–2025.
45%
Good days in 2025
52
Median daily AQI, 2025
0
Days above 100 in 2025
365
Days with an AQI in 2025 (of 365)
In 2025, EPA reported a daily Air Quality Index (AQI) for Santa Barbara, California on 365 days. 164 of those days (45%) were in the Good range, and the median daily AQI was 52. That median is higher than the typical monitored county in California (median 45.5 across 46 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 283 days. Across the years with fuller monitoring, the share of Good days rose: an average of 39% in 1980–1982 versus 54% in 2023–2025.
How the days broke down each year
Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Typical and high-end AQI over time
The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.
Median daily AQI
90th-percentile daily AQI
Main pollutant by day, 2025
On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.
Pollutant
Days as main pollutant
Share of monitored days
Fine particles (PM2.5)
283
78%
Ozone
74
20%
Coarse particles (PM10)
8
2%
Year-by-year data
Annual AQI summary by year
Year
Days with AQI
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Median AQI
90th pct.
Max AQI
Main pollutant
2025
365
164
201
0
0
0
0
52
61
87
PM2.5
2024
366
193
171
2
0
0
0
49
60
146
PM2.5
2023
365
232
133
0
0
0
0
45
59
95
PM2.5
2022
365
198
167
0
0
0
0
48
60
93
PM2.5
2021
365
240
124
1
0
0
0
44
60
101
PM2.5
2020
366
199
154
9
4
0
0
48
68
174
PM2.5
2019
365
242
122
1
0
0
0
45
63
105
Ozone
2018
365
173
190
2
0
0
0
51
67
114
PM2.5
2017
365
181
167
6
8
2
1
51
74
313
PM2.5
2016
366
191
163
9
2
0
1
50
69
313
Ozone
2015
365
168
196
1
0
0
0
51
69
101
PM2.5
2014
365
161
198
4
2
0
0
52
66
159
PM2.5
2013
365
149
213
3
0
0
0
52
65
122
PM2.5
2012
366
158
205
3
0
0
0
52
67
136
Ozone
2011
365
90
272
2
1
0
0
55
66
161
PM2.5
2010
365
219
139
7
0
0
0
47
67
143
Ozone
2009
365
251
103
7
4
0
0
45
71
172
Ozone
2008
366
223
131
11
1
0
0
47
77
151
Ozone
2007
365
215
129
19
2
0
0
49
84
183
Ozone
2006
365
215
134
15
1
0
0
49
80
165
Ozone
2005
365
225
127
13
0
0
0
47
84
140
Ozone
2004
366
205
142
17
2
0
0
49
87
192
Ozone
2003
365
193
132
35
5
0
0
49
101
192
Ozone
2002
365
188
142
32
3
0
0
50
100
161
Ozone
2001
365
208
119
36
1
1
0
49
101
201
Ozone
2000
366
201
127
36
2
0
0
48
101
154
Ozone
1999
365
169
165
30
0
1
0
51
97
205
Ozone
1998
365
208
110
42
3
2
0
49
112
216
Ozone
1997
365
173
146
42
3
1
0
51
105
203
Ozone
1996
366
153
153
44
15
1
0
54
119
218
Ozone
1995
365
150
157
45
11
2
0
54
119
214
Ozone
1994
365
115
198
42
9
1
0
64
108
212
Ozone
1993
365
153
151
50
10
1
0
54
122
205
Ozone
1992
366
121
175
54
14
2
0
64
126
221
Ozone
1991
365
73
194
73
23
2
0
71
140
208
Ozone
1990
365
105
171
64
22
3
0
68
136
238
Ozone
1989
365
77
185
77
21
5
0
76
133
275
Ozone
1988
366
67
195
79
25
0
0
75
140
192
Ozone
1987
365
125
161
57
19
3
0
64
133
239
Ozone
1986
365
107
173
63
18
4
0
71
133
224
Ozone
1985
365
149
181
27
7
1
0
57
100
237
Ozone
1984
366
139
199
16
10
2
0
57
90
214
Ozone
1983
365
186
154
15
5
5
0
50
93
214
Ozone
1982
365
147
186
27
4
1
0
57
93
227
Ozone
1981
365
140
185
33
5
2
0
58
101
235
Ozone
1980
366
136
178
43
7
2
0
61
108
213
Ozone
What this data can and can’t tell you
It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.
It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.
Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.
Counties in California with a similar median AQI in 2025
