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Simulating lightning NO production in CMAQv5.2: performance evaluations.

ABSTRACT: This study assesses the impact of the lightning nitric oxide (LNO) production schemes in the Community Multiscale Air Quality (CMAQ) model on ground-level air quality as well as aloft atmospheric chemistry through detailed evaluation of model predictions of nitrogen oxides (NO x ) and ozone (O3) with corresponding observations for the US. For ground-level evaluations, hourly O3 and NO x values from the U.S. EPA Air Quality System (AQS) monitoring network are used to assess the impact of different LNO schemes on model prediction of these species in time and space. Vertical evaluations are performed using ozonesonde and P-3B aircraft measurements during the Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) campaign conducted in the Baltimore- Washington region during July 2011. The impact on wet deposition of nitrate is assessed using measurements from the National Atmospheric Deposition Program's National Trends Network (NADP NTN). Compared with the Base model (without LNO), the impact of LNO on surface O3 varies from region to region depending on the Base model conditions. Overall statistics suggest that for regions where surface O3 mixing ratios are already overestimated, the incorporation of additional NO from lightning generally increased model overestimation of mean daily maximum 8 h (DM8HR) O3 by 1-2 ppb. In regions where surface O3 is underestimated by the Base model, LNO can significantly reduce the underestimation and bring model predictions close to observations. Analysis of vertical profiles reveals that LNO can significantly improve the vertical structure of modeled O3 distributions by reducing underestimation aloft and to a lesser degree decreasing overestimation near the surface. Since the Base model underestimates the wet deposition of nitrate in most regions across the modeling domain with the exception of the Pacific Coast, the inclusion of LNO leads to reduction in biases and errors and an increase in correlation coefficients at almost all the NADP NTN sites. Among the three LNO schemes described in Kang et al. (2019), the hNLDN scheme, which is implemented using hourly observed lightning flash data from National Lightning Detection Network (NLDN), performs best for comparisons with ground-level values, vertical profiles, and wet deposition of nitrate; the mNLDN scheme (the monthly NLDN-based scheme) performed slightly better. However, when observed lightning flash data are not available, the linear regression-based parameterization scheme, pNLDN, provides an improved estimate for nitrate wet deposition compared to the base simulation that does not include LNO.

SUBMITTER: Kang D

PROVIDER: S-EPMC6913039 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Simulating lightning NO production in CMAQv5.2: performance evaluations.

Kang Daiwen D Foley Kristen M KM Mathur Rohit R Roselle Shawn J SJ Pickering Kenneth E KE Allen Dale J DJ

Geoscientific model development 20190101 10

This study assesses the impact of the lightning nitric oxide (LNO) production schemes in the Community Multiscale Air Quality (CMAQ) model on ground-level air quality as well as aloft atmospheric chemistry through detailed evaluation of model predictions of nitrogen oxides (NO x ) and ozone (O3) with corresponding observations for the US. For ground-level evaluations, hourly O3 and NO x values from the U.S. EPA Air Quality System (AQS) mo ...[more]

PMID: 31844504

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Project description:Background:Current evaluation methods are mismatched with the speed of health care innovation and needs of health care delivery partners. We introduce a qualitative approach called the lightning report method and its specific product-the "Lightning Report." We compare implementation evaluation results across four projects to explore report sensitivity and the potential depth and breadth of lightning report method findings. Methods:The lightning report method was refined over 2.5 years across four projects: team-based primary care, cancer center transformation, precision health in primary care, and a national life-sustaining decisions initiative. The novelty of the lightning report method is the application of Plus/Delta/Insight debriefing to dynamic implementation evaluation. This analytic structure captures Plus ("what works"), Delta ("what needs to be changed"), and Insights (participant or evaluator insights, ideas, and recommendations). We used structured coding based on implementation science barriers and facilitators outlined in the Consolidated Framework for Implementation Research (CFIR) applied to 17 Lightning Reports from four projects. Results:Health care partners reported that Lighting Reports were valuable, easy to understand, and they implied reports supported "corrective action" for implementations. Comparative analysis revealed cross-project emphasis on the domains of Inner Setting and Intervention Characteristics, with themes of communication, resources/staffing, feedback/reflection, alignment with simultaneous interventions and traditional care, and team cohesion. In three of the four assessed projects, the largest proportion of coding was to the clinic-level domain of Inner Setting-ranging from 39% for the cancer center project to a high of 56% for the life-sustaining decisions project. Conclusions:The lightning report method can fill a gap in rapid qualitative approaches and is generalizable with consistent but flexible core methods. Comparative analysis suggests it is a sensitive tool, capable of uncovering differences and insights in implementation across projects. The Lightning Report facilitates partnered evaluation and communication with stakeholders by providing real-time, actionable insights in dynamic health care implementations.

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Dataset Information

Simulating lightning NO production in CMAQv5.2: performance evaluations.

Publications

Simulating lightning NO production in CMAQv5.2: performance evaluations.

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