Table 2.
Monthly average of PM2.5 concentrations (μg/m3) by state in the month of April of the years 2015–2020 from the AQS sites. The last column shows the percent change in 2020 with respect to the 20152019 mean
| State | No. sites | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | |
|---|---|---|---|---|---|---|---|---|
| Alabama | 4 | 7.94 | 7.56 | 8.82 | 7.26 | 7.64 | 8.59 | + 9.5% |
| Alaska | 4 | 3.45 | 3.57 | 4.36 | 3.43 | 4.45 | 3.83 | − 0.6% |
| Arizona | 13 | 5.67 | 5.82 | 6.9 | 8.13 | 5.03 | 4.75 | − 24.7% |
| Arkansas | 4 | 7.01 | 7.12 | 8.12 | 6.98 | 7.51 | 7.54 | + 2.6% |
| California | 61 | 7.06 | 6.65 | 6.35 | 7.93 | 6.31 | 5.26 | − 23.3% |
| Colorado | 8 | 5.31 | 3.65 | 4.63 | 5.87 | 5.26 | 5.21 | + 5.4% |
| Connecticut | 8 | 4.8 | 5.54 | 3.81 | 5.61 | 5.32 | 5.75 | + 14.6% |
| Delaware | 3 | 5.73 | 5.65 | 6.21 | 6.48 | 5.91 | 7.09 | + 18.2% |
| District Of Columbia | 1 | 6.21 | 6.68 | 7.11 | 8 | 6.33 | 4.67 | − 32.0% |
| Florida | 16 | 7.01 | 7 | 7.41 | 7.68 | 6.39 | 9.52 | + 34.1% |
| Georgia | 10 | 7.87 | 8.31 | 8.52 | 8.25 | 8.83 | 8.44 | + 1.0% |
| Hawaii | 7 | 5.96 | 4.72 | 6.68 | 4.26 | 3.2 | 3.32 | − 33.1% |
| Idaho | 5 | 4.47 | 5.51 | 4.21 | 4.43 | 3.55 | 5.72 | + 29.0% |
| Illinois | 14 | 8.23 | 7.67 | 7.06 | 8.03 | 7.43 | 8.11 | + 5.5% |
| Indiana | 15 | 7.5 | 8.21 | 6.17 | 6.64 | 6.21 | 8.47 | + 21.9% |
| Iowa | 9 | 7.78 | 6.97 | 6.18 | 7.09 | 5.65 | 8.71 | + 29.3% |
| Kansas | 3 | 6.34 | 6.21 | 6.85 | 8.31 | 8.77 | 11.47 | + 57.2% |
| Kentucky | 12 | 6.97 | 7.03 | 6.27 | 6.48 | 6.77 | 8.04 | + 19.9% |
| Louisiana | 4 | 7.81 | 7.06 | 8.43 | 7.52 | 6.84 | 7.74 | + 2.8% |
| Maine | 6 | 5.16 | 5.64 | 4.93 | 4.46 | 3.63 | 4.05 | − 15.0% |
| Maryland | 10 | 6.93 | 6.75 | 5.74 | 6.46 | 4.33 | 4.81 | − 20.4% |
| Massachusetts | 9 | 4.67 | 5.08 | 3.02 | 5.6 | 4.68 | 5.71 | + 23.9% |
| Michigan | 11 | 6.7 | 6.7 | 5.52 | 6.48 | 6.33 | 7.1 | + 11.9% |
| Minnesota | 18 | 5.09 | 5.66 | 5.06 | 6.22 | 4.88 | 5.73 | + 6.5% |
| Mississippi | 7 | 7.98 | 7.49 | 8.32 | 8.27 | 6.97 | 10.15 | + 30.0% |
| Missouri | 13 | 7.65 | 6.3 | 6.46 | 7.33 | 7.33 | 6.6 | − 5.9% |
| Montana | 11 | 5.02 | 4.57 | 4.07 | 4.81 | 3.7 | 4.21 | − 5.1% |
| Nebraska | 2 | 8.02 | 6.65 | 9.82 | 9.77 | 6.1 | 8.17 | + 1.2% |
| Nevada | 6 | 6.16 | 4.81 | 4.57 | 5.25 | 3.23 | 4.11 | − 14.4% |
| New Hampshire | 5 | 4.3 | 4.2 | 3.18 | 4.11 | 3.34 | 4.01 | + 4.8% |
| New Jersey | 3 | 5.69 | 7.27 | 7.32 | 7.17 | 6.09 | 5.84 | − 12.9% |
| New Mexico | 5 | 7.34 | 5.05 | 7.02 | 7.93 | 5.58 | 4.87 | − 26.0% |
| New York | 7 | 5.32 | 4.99 | 4.38 | 4.93 | 4.92 | 4.5 | − 8.3% |
| North Carolina | 13 | 6.78 | 7.25 | 7.16 | 6.53 | 6.4 | 5.41 | − 20.7% |
| North Dakota | 6 | 4.65 | 3.24 | 4.33 | 5.26 | 3.58 | 4.2 | − 0.3% |
| Ohio | 12 | 7.49 | 7.86 | 5.55 | 6.82 | 6.68 | 6.99 | + 1.6% |
| Oklahoma | 9 | 7.32 | 7.31 | 7.52 | 8.78 | 7.71 | 8.19 | + 6.0% |
| Oregon | 12 | 5.3 | 4.94 | 4.28 | 5.14 | 4.24 | 5.17 | + 8.2% |
| Pennsylvania | 24 | 7.41 | 7.01 | 7.64 | 6.99 | 6.52 | 6.97 | − 2.0% |
| Rhode Island | 5 | 4.84 | 5.2 | 4.56 | 6.01 | 3.3 | 4.08 | − 14.7% |
| South Carolina | 6 | 7.33 | 6.95 | 7.95 | 6.64 | 6.6 | 6.62 | − 6.7% |
| South Dakota | 8 | 6.65 | 4.93 | 5.35 | 5.54 | 3.68 | 5.01 | − 4.2% |
| Tennessee | 11 | 6.41 | 6.68 | 6.8 | 6.45 | 6.5 | 6.23 | − 5.1% |
| Texas | 11 | 10.04 | 8.84 | 9.13 | 8.79 | 8.76 | 10.27 | + 12.7% |
| Utah | 7 | 5.6 | 3.3 | 3.47 | 4.59 | 3.03 | 3.79 | − 5.2% |
| Vermont | 4 | 4.32 | 4.24 | 3.27 | 4.69 | 4.48 | 4.73 | + 12.6% |
| Virginia | 6 | 5.74 | 5.76 | 6.33 | 5.31 | 5.75 | 5.66 | − 2.0% |
| Washington | 11 | 5.57 | 6.5 | 3.53 | 4.01 | 4.17 | 5.11 | + 7.4% |
| Wisconsin | 18 | 5.45 | 7.47 | 4.58 | 5.46 | 6.68 | 7.49 | + 26.3% |
| Wyoming | 3 | 4.04 | 2.75 | 2.73 | 3.3 | 2.57 | 1.73 | − 43.8% |