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

该奖项将支持作为深对流云和化学（DC 3）现场活动的一部分的建模活动。 DC 3将研究深中纬度大陆对流云的影响，包括其动力学，物理和闪电过程，对对流层上部的组成和化学。 该项目的工作重点是改进闪电产生氮氧化物（LNOx）的模型表示，以及对每次闪光和每单位闪光长度产生的量的估计，以及由此产生的NOx混合比的垂直分布。 案例研究将使用WRF-Chem模型进行模拟。 将对DC 3观测结果和模式输出进行分析，以确定风暴云和顺风云外流中臭氧变化的幅度。在DC 3使命之前，将使用WRF模型模拟DC 3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，这可能表明闪电预测方案的改进或变化。 然后，该团队将通过分析和解释WRF-Chem在此期间运行的预测结果，参与2011年5月的DC 3试飞。 随后将对预测进行评估，并在DC 3使命之前对LNOx算法进行可能的进一步改进。 在2012年5月至6月的DC 3使命期间，学生们将在现场解释WRF-Chem预测输出，以制定飞行计划。 他们将检查可能发生对流的区域，对流类型，预测的闪光率的大小，NOx的产生量，对流流出羽流的高度，以及下游臭氧的产生。 在使命之后，将选择个别观测到的风暴进行个案研究模拟。 各种闪电氮氧化物计划将纳入WRF-Chem，并使用DC 3观测进行评估。 案例研究模拟的目的是通过与氮氧化物铁砧观测结果的比较，估计每次闪光和每单位闪光长度的闪电氮氧化物产生量。 将利用实地数据对风暴内和风暴顺风处对流输送和化学作用引起的臭氧变化的模型估计值进行评估。 垂直风切变，闪光长度和闪电氮氧化物生产之间的关系将被检查，以及大气气溶胶含量和闪光率之间的关系。该奖项将支持两名研究生参与DC 3的准备，现场活动，任务后的分析和建模。 对LNOx理解的提高将应用于更大规模的化学和气候模型。

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.