EnviroNearby

Valdez-Cordova, Alaska air quality history

Daily Air Quality Index summaries from EPA monitors in Valdez-Cordova, Alaska, 1980–1981.

95%
Good days in 1981
29
Median daily AQI, 1981
4
Days above 100 in 1981
362
Days with an AQI in 1981 (of 365)

In 1981, EPA reported a daily Air Quality Index (AQI) for Valdez-Cordova, Alaska on 362 days. 343 of those days (95%) were in the Good range, and the median daily AQI was 29. That median is about the same as the typical monitored county in Alaska (median 29 across 3 counties), and lower than the typical monitored U.S. county (38). The main pollutant was ozone on 226 days.

The most recent year with data for this county is 1981; EPA's files for 1982–2025 contain no row for it, which usually means its monitors stopped reporting.

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.

Share of monitored days in each AQI category, by year0%25%50%75%100%1980: Good 359 of 361 days1980: Moderate 2 of 361 days19801981: Good 343 of 362 days1981: Moderate 15 of 362 days1981: Unhealthy for Sensitive Groups 2 of 362 days1981: Unhealthy 2 of 362 days1981
  • 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 and 90th-percentile daily AQI, by year0501001980: 90th percentile AQI 441981: 90th percentile AQI 431980: Median AQI 261981: Median AQI 2919801981
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 1981

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.

PollutantDays as main pollutantShare of monitored days
Ozone22662%
Nitrogen dioxide (NO₂)13638%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
19813623431522002943197Ozone
198036135920000264454Ozone

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.

All monitored counties in Alaska

Source: U.S. EPA AirData, “Annual AQI by County” files for 1980–1981 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem