Corrigendum to 'Chemical mass balance source apportionment for combined PM2.5 measurements from U.S. non-urban and urban long-term networks' [Atmos. Environ. 44 (2010) 4908–4918]

A mislabeling of sampling sites was discovered after final proofing of the paper. GRRI data were labeled as BLMO and BLMO data were labeled as GRRI in Table 2e3, Figs. 2 and 3, and supplemental Table S1 and S4. Texts that explain the tables and figures also need to be corrected. Since the two sites were discussed as a group for the most part, the mislabeling does not change the conclusions of the paper except for Section 5.2: Inter-network differences. In Section 5.2, GRRI source apportionment results were compared with those from ROC (see the 5th and 6th paragraphs). It was concluded that ROC and GRRI (really BLMO) showed similar contributions from regional sources secondary sulfate (including coal-fired utility), secondary nitrate, and soil dust. When ROC is compared with the actual GRRI, secondary sulfate contributions are similar (2.67 versus 2.72 mgm 3), but ROC shows higher secondary nitrate, secondary organic carbon, soil dust, Ca-rich dust, engine exhaust, and road salt contributions than GRRI. Biomass burning contributions are 36e39% lower at ROC. These differences may be explained by local activities around ROC (e.g., traffic, construction, and de-icing) and GRRI (e.g., campfires). The reconstructed PM2.5 concentrations were 102% and 99% of measured PM2.5 mass at ROC and GRRI, respectively. Other changes include