NASA ROSES08: Applying NASA Observations, Models and IT for Air Quality Proposal

Decision-making Activities Description and Baseline Performance (2page)

In case of natural exceptional pollution events, such as forest fire smoke the air quality analysts are typically affiliated with the impacted states. They submit their reports to the federal EPA as part of their request for exceptional event waivers. EPA analysts review the requests and make their recommendations to the EPA regulatory decision makers. In this case, the DSS needs to support both state and the federal analysts.

EPA determines compliance with the National Ambient Air Quality Standards (NAAQS) based upon ambient air quality measurements using Federal Reference Method (FRM) monitors. Based on the 2006 ammendment of the PM2.5 NAAQS, the Exceptional Event Rule provides for the exclusion of data strongly influenced by impacts from "exceptional events," such as smoke from a wildfire or dust from abnormally high winds. States "flag" data for those days that they believe to be impacted by exceptional events. Such flagged days if concurred with by EPA, may be given special consideration in the compliance calculations.

Need to incorporate the forecasting/FASTNet before States flag.

Exceptional Event flagging decisions are performed in three organizations: States, Regional EPA Offices and Federal EPA. The States need to decide whether a particular sample is to be flagged or not. The EPA Regional Offices need to evaluate the submitted flagged requests and recommend approval. The Federal EPA makes the final decision whether a requested EE flag to be approved.

in operational mode main interaction is between States and Region

The role of the Feds;
ensure consistency
evaluation of special cases
interpretation of rule

DSS is not push button, it requires decisions to be made about data used, tools to apply and what evidence to bring for justification. Templates for types of event justification.  

States have to publish flagged AQ days

What are the reasons and needs for improving (creating) it?

Currently, in making their flagging decisions States use ad hoc methods at their disposal. The formal decision support system to aide the States does not exist. The State's decision whether to flag a sample is reached either from the general knowledge that an Exceptional Event has occured or from scanning their monitoring data for anomolous pattern. The general knowledge that an EE has occured, typically arises from media reports of fires, dust storms and other EEs. Increasingly, reports from the Public in the form of blogs, YouTube and other shared public content can be used to identify Exceptional Events. Another method of identifying EEs is to scan the air quality monitoring data for anomolously high concentrations, particularly those that are likely contributors to non-compliance of a given site. It is believed that depending on the situation, both methods are being used in flagging decisions.

Both Regional and Federal EPA Offices need to evaluate the submitted EE claims. The EE Rule is intentionally vague on the types of evidence and analyzes. As a consequence, the submissions are highly variable; some are very detailed and technical while others are brief and descriptive. The EPA Regional Offices currently use ad hoc methods to understand the events, to evaluate the claims, and to make their recommendation. The lack of formal procedures and tools makes evaluation difficult and uneven.

The Exceptional Event Rule... formalizes the procedures ... The agencies submitting the flagged data are required to provide appropriate justification for the exceptional event flags.

What analyses does (will) it support and what actions and decisions are (will be) made?

The main scientific, technical challenge arises from the fact that many different source types contribute to PM2.5 concentrations. Some sources are anthropogenic, others are natural; some are located nearby, others can be located far away. Emissions from natural and 'extra-jurisdictional' sources, such as biomass fires and windblown dust or intercontinental pollution transport can contribute to severe episodic PM events, i.e. short-term concentration spikes. However, accounting for the contributions of these extra jurisdictional events in the implementation of the NAAQS is still under development.

Real-time continuous PM monitoring provides the record for short term event detection. Time-integrated and less frequent speciated PM samples provide the chemical signatures for specific aerosol types, such as smoke or dust. Satellite images delineate both the synoptic-scale as well as fine-scale features of PM events under cloudfree conditions. The full integration of these diverse PM data arising from a variety of measurements is still a major challenge for the data analyst. Air quality models that assimilate the various observations could serve as effective data integration platform. Unfortunately, the science and technology of such data assimilation is not yet available for the modeling and data analysis communities.

Flagging procedure has to be in accordance with section 40 CFR 50.14 (c)(3)(iii) of the EE rule. Preparing and evaluating the evidence for flagged data is a technically challenging task both for the State and the Regulatory offices. It requires:

Access to a diverse array of data sources illustrating various aspects of the exceptional event
Integration of the heterogeneous data sources, frequently incomplete and incompatible
Demanding data analysis and to establish "clear causal relationship" between the EE and the exceedance
Finally, the Rule requires a demonstration that the exceedance would not have occurred but for the presence of the EE.

The above requirements place high demand on the resources and skills of the analysts at the State, Region and Federal level. Many State and Regional AQ management offices lack the means for detecting, flagging and documenting exceptional events.

Fortunately, there are now outstanding opportunities to develop executable, credible and reasonably simple methods for PM2.5 Exceptional Event analysis. In the past, the EPA evaluation of the State-provided data did not benefit from tools and sources of information which are now available.

The purpose of the Excepitonal Event DSS (EE DSS) for the preparation of technical documantation and supporting information for exceptional event data claims. The EE flags and the flag justification reports are prepared by the individual States, the primary users of the DSS are the States. However, since the EE flag claims are evaluated by Regional and Federal EPA offices, they also represent major user groups.

What measures/metrics do (will) its users employ to determine the value or quality of their decision-making?