Daily Air Quality Index summaries from EPA monitors in Caroline, Virginia, 1993–2025.
97%
Good days in 2025
35
Median daily AQI, 2025
0
Days above 100 in 2025
243
Days with an AQI in 2025 (of 365)
In 2025, EPA reported a daily Air Quality Index (AQI) for Caroline, Virginia on 243 days. 235 of those days (97%) were in the Good range, and the median daily AQI was 35. That median is about the same as the typical monitored county in Virginia (median 37 across 25 counties), and lower than the typical monitored U.S. county (40). The main pollutant was ozone on 243 days. Across the years with fuller monitoring, the share of Good days rose: an average of 69% in 1993–1995 versus 96% in 2023–2025.
EPA did not report an AQI for every day of 2025 here (243 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.
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
Ozone
243
100%
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
243
235
8
0
0
0
0
35
45
74
Ozone
2024
223
220
3
0
0
0
0
37
46
77
Ozone
2023
243
224
19
0
0
0
0
40
50
97
Ozone
2022
243
236
7
0
0
0
0
36
46
67
Ozone
2021
228
210
16
2
0
0
0
35
49
108
Ozone
2020
235
232
3
0
0
0
0
34
45
64
Ozone
2019
239
229
10
0
0
0
0
39
48
84
Ozone
2018
241
219
22
0
0
0
0
36
49
84
Ozone
2017
245
228
17
0
0
0
0
39
49
87
Ozone
2016
182
160
21
1
0
0
0
36
51
112
Ozone
2015
204
185
19
0
0
0
0
40
50
87
Ozone
2014
184
163
21
0
0
0
0
42
51
84
Ozone
2013
169
154
15
0
0
0
0
37
50
90
Ozone
2012
213
160
43
10
0
0
0
43
77
133
Ozone
2011
203
171
27
5
0
0
0
40
64
140
Ozone
2010
213
131
76
6
0
0
0
46
77
143
Ozone
2009
207
183
24
0
0
0
0
39
54
100
Ozone
2008
214
159
43
11
1
0
0
43
74
161
Ozone
2007
213
111
84
17
1
0
0
50
97
151
Ozone
2006
214
150
52
9
3
0
0
44
80
154
Ozone
2005
200
132
52
14
2
0
0
46
97
169
Ozone
2004
214
169
33
11
1
0
0
42
77
151
Ozone
2003
207
146
53
5
2
1
0
43
87
202
Ozone
2002
303
218
67
15
3
0
0
38
87
185
Ozone
2001
357
263
65
25
4
0
0
35
93
174
Ozone
2000
351
296
45
9
1
0
0
31
64
156
Ozone
1999
349
244
59
33
13
0
0
35
112
195
Ozone
1998
313
205
64
36
6
2
0
41
112
210
Ozone
1997
353
250
60
37
6
0
0
37
108
195
Ozone
1996
351
258
71
21
1
0
0
32
90
166
Ozone
1995
359
273
61
23
2
0
0
30
87
164
Ozone
1994
360
255
68
36
1
0
0
37
101
151
Ozone
1993
275
166
62
36
11
0
0
44
122
174
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 Virginia with a similar median AQI in 2025
