Review of the NARSTO Draft Report: An Assessment of Tropospheric Ozone Pollution--A North American Perspective (2000)

In this chapter, the committee presents its view of opportunities for strengthening ozone management that the authors of the NARSTO assessment document might consider addressing. The document cannot be expected to resolve these difficulties, but it can and should identify the set of needs that its authors believe are crucial for future progress. Determination of what these needs are is the first step for NARSTO as it moves forward in future phases of its operations. The following, presented in no order of priority, reflect the committee 's views.

The NARSTO assessment document quite correctly identifies the crucial importance of addressing the many uncertainties associated with emissions characterization. However, that finding is not new; it has been identified as a critical issue in many previous studies, and yet the problem remains. To solve it, a well-targeted program should be devised and implemented. Such an effort would strengthen source characterization measurement and modeling programs, identify and implement—as appropriate —other methods to estimate emissions (e.g., inverse modeling), and structure emissions inventories so that they are more suited to the control-strategy design process. That effort would also allow for greater understanding of the relative importance of various sources of precursor emissions.

Throughout the NARSTO assessment document there are numerous references to uncertainties in the understanding of key physical processes as well as of many inputs to models. There are always uncertainties. What is critically important is to identify those uncertainties, using already established procedures, that contribute most to uncertainties in outcomes. In this regard, there are two critical steps that should be taken in ozone analysis and control. The first step is to begin a process for determining the magnitude of the

uncertainties that really matter. The second step is to implement a method for assessing how they influence one another, as well as the final results. Effective uncertainty analysis would also provide a much more-rigorous rationale for setting priorities for research and data collection.

A key determinant of the success of any plan is its execution. An important question is whether sufficient human resources will be available in the near future to devise, operate, and manage effective ozone-control programs. For example, will there be an adequate number of experts to obtain, understand, and interpret the outputs of air-quality models that are to be applied to the ozone problems in North America? Adequate investments in education and training are needed to address tropospheric ozone problems.

A major problem in ozone-control management is the need to engage a larger scientific community by clearly identifying those issues that might be of interest to other scientists and engineers who are in areas such as statistics and data analysis, applied mathematics for combinatorial optimization, instrumentation, and meteorology. Although their work may not be readily associated with the group of researchers addressing the ozone problem, it can provide further insight into the issues at hand. Research and development at the National Laboratories is one example.

There is a critical need for a comprehensive analysis of the data that has already been collected. As noted in the critical review paper by Solomon et al. (In press), approximately $600 million has been spent on field programs. Much of the data collected has not been analyzed, and the information gathered has not yet been fully incorporated in scientific understanding because of a lack of resources.