Production of Nitrogen Oxides (NOx) by Lightning during the Deep Convective Clouds and Chemistry (DC3) Experiment

深对流云和化学 (DC3) 实验期间闪电产生氮氧化物 (NOx)

• 批准号: 1063479
• 负责人: Kenneth Pickering
• 金额: $ 42.86万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-15 至 2015-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1063479&HistoricalAwards=false
• 关键词: Production; Nitrogen; Oxides; NOx; Lightning

This award will support modeling activities as part of the Deep Convective Clouds and Chemistry (DC3) field campaign. DC3 will study the impact of deep, mid-latitude continental convective clouds, including their dynamical, physical, and lightning processes, on upper tropospheric composition and chemistry. Efforts in this project will be focused on improving model representation of the production of nitrogen oxides by lightning (LNOx) and estimates of the magnitude of the production per flash and per unit flash length, as well the vertical distribution of the resulting NOx mixing ratios. Case studies will be simulated using the WRF-Chem model. DC3 observations and the model output will be analyzed to determine the magnitude of resulting ozone changes both within the storm clouds and in the downwind cloud outflow. Prior to the DC3 mission, test cases from the DC3 regions will be simulated using the WRF model. The model output will be compared with Lightning Mapping Array data, which may suggest improvements or changes in the lightning prediction scheme. The team will then participate in the May 2011 DC3 test flights through analysis and interpretation of output from WRF-Chem forecasts run operationally for the period. This will be followed up with evaluation of the forecasts and making possible further improvements to the LNOx algorithms prior to the DC3 mission. During the May-June 2012 DC3 mission, students will be in the field interpreting the WRF-Chem forecast output for flight planning. They will examine likely areas where convection may occur, types of convection, magnitudes of predicted flash rates, amount of NOx production, altitudes of convective outflow plumes, and downstream ozone production. Following the mission, individual observed storms for case study simulations will be selected. Various lightning NOx schemes will be incorporated into WRF-Chem and evaluated using DC3 observations. The case study simulations will be designed to yield estimates of lightning NOx production per flash and per unit flash length through comparisons with the anvil observations of NOx. Model estimates of ozone changes due to convective transport and chemistry within and downwind of storms will be evaluated using field data. Relationships between vertical wind shear, flash length and lightning NOx production will be examined, as well as relationships between atmospheric aerosol content and flash rates.This award will support the participation of two graduate students in DC3 preparation, field activities, and post-mission analysis and modeling. Improvement in the understanding of LNOx will be applied to larger-scale chemistry and climate models.

该奖项将支持建模活动，作为深度对流云与化学（DC3）现场运动的一部分。 DC3将研究深层，中纬度大陆对流云的影响，包括它们的动力学，物理和闪电过程，对对流层的上层组成和化学。 该项目中的努力将集中在改善闪电（LNOX）的氮氧化物生产的模型表示以及对每单位闪存长度和每单位闪存长度的幅度的估计，以及所得NOX混合比的垂直分布。 案例研究将使用WRF-CHEM模型进行模拟。 将分析DC3观测值和模型输出，以确定风暴云和下风云流出内部臭氧的变化的幅度。在执行DC3任务之前，将使用WRF模型模拟DC3区域的测试用例。 模型输出将与闪电映射阵列数据进行比较，这可能表明改进或闪电预测方案的变化。 然后，该团队将通过分析和解释WRF-Chem预测的分析和解释在此期间运行运行的WRF-Chem预测，参加2011年5月的DC3测试飞行。 随后将对预测进行评估，并在DC3任务之前对LNOX算法进行进一步的改进。 在2012年5月至6月的DC3任务中，学生将在现场解释WRF-Chem预测输出以进行飞行计划。 他们将检查可能发生对流的可能区域，对流的类型，预测的闪光速率的幅度，NOX产生量，对流流出羽流的高度以及下游的臭氧产生。 执行任务后，将选择单个案例研究模拟的风暴。 各种闪电NOX方案将纳入WRF-Chem，并使用DC3观测值进行评估。 案例研究模拟将旨在通过与NOX的砧座观测值进行比较，从而产生每次闪光的闪电NOx产生和每单位闪存长度的估计。 风暴内部和下风内的臭氧变化的模型估计值将使用现场数据评估。 将检查垂直风剪，闪存长度和闪电NOX生产之间的关系，以及大气气溶胶含量和闪光灯的关系。该奖项将支持两名研究生参与DC3准备，现场活动，后期活动后分析和建模。 对LNOX的理解的改善将应用于大规模的化学和气候模型。