Document ba4aOKbj30nzKQje2X7q5OyYy

Message From: Sent: To: CC: Subject: Jones, Enesta [/0=EXCHANGELABS/OU=EXCHANGE ADMINISTRATIVE GROUP (FYDIBOHF23SPDLT)/CN=RECIPIENTS/CN=65B8E6C6E5CA4A7A9AE85D98A4C8EEDB-EJONES02] 4/13/2018_ 12:09:24 PM_______ Eli KintiscH Ex. 6 i L__________________________________________ Press [/o=ExchangeLabs/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=b293283291dc44eOb5dlc36be9281d8a-Press] Re: How the Beijing experience helped push EPA to revise its NowCast methodology Eli, On background: --I'd like to ask about how that Quality Assurance work was adjusted. Response: The AirNow system features a robust set of QA/QC procedures, designed to balance data quality with timely delivery. These procedures were developed and honed over the 20-year history of the AirNow program. Our work with the U S. Embassy in Beijing required us to change parameters within our QA system to reflect higher concentrations than we typically experience in the U.S. --You indicated you were interested in AirNow's work with the U.S. Embassy in Beijing. You also indicated you were interested in our updates to the NowCast. Response: In order to relate hourly particle pollution measurements to the 24-hour Air Quality Index, AirNow uses an algorithm called the NowCast. The program has used an algorithm to map particle pollution since the maps were added to the AirNow.gov site about 2004. Over time, we found that while the algorithm did a good job when air quality was stable, it was slow to respond when conditions were rapidly changing - the type of conditions we can see here in the U.S. during wildfires, and that also occur in Beijing. In 2013, we updated the NowCast so it is more responsive when air quality is rapidly changing - yet still reflects a longer-term average when air quality is stable. Because the new method responds more quickly, the public gets information about worsening air quality sooner - and that can help them modify activities to reduce their pollution exposure. We included monitor data from the U.S. Embassy in Beijing as we were testing the new NowCast, in addition to domestic locations, to help us understand how it would perform in air quality conditions at home and abroad. Today, the updated NowCast is used to show current particle pollution air quality on the U.S. map at www.airnow.gov, and at the AirNow Department of State Page, which shows air quality at U.S. Embassies and Consulates with monitors, available at https://www.aimow, gov/index.cfm?action=airnow. global summary . Sierra Club v. EPA 18cv3472 NDCA Tier 13 ED 002061 00017086-00001