Western North American FLEXPART Back Trajectory 2012 Data

WNA-FLEXPART-BackTraj-2012 is the 2012 Western North America Back Trajectory data using the FLEXible PARTicle (FLEXPART) dispersion model. Data collection for this product is complete.

Backward simulations of airmass transport using a Lagrangian Particle Dispersion Model (LPDM) framework can establish source-receptor relationships (SRRs), supporting analysis of source contributions from various geospatial regions and atmospheric layers to downwind observations. In this study, we selected receptor locations to match gridded ozone observations over Western North America (WNA) from ozonesonde, lidar, commercial aircraft sampling, and aircraft campaigns (1994-2021). For each receptor, we used the FLEXible PARTicle (FLEXPART) dispersion model, driven by ERA5 reanalysis data, to achieve 15-day backwards SRR calculations, providing global simulations at high temporal (hourly) and spatial (1° x 1°) resolution, from the surface up to 20 km above ground level. This product retains detailed information for each receptor, including the gridded ozone value product, allowing the user to illustrate and identify source contributions to various subsets of ozone observations in the troposphere above WNA over nearly 3 decades at different vertical layers and temporal scales, such as diurnal, daily, seasonal, intra-annual, and decadal. This model product can also support source contribution analyses for other atmospheric components observed over WNA, if other co-located observations have been made at the spatial and temporal scales defined for some or all of the gridded ozone receptors used here.

These data products were generated with support from NASA’s Atmospheric Composition Campaign Data Analysis and Modeling program and the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center (award SMD-20-28429430). The critical role of in situ measurements collected by many individual research teams, as well as contributions in model development and intermediate analyses, is gratefully acknowledged.

For further information, please contact the authors of the manuscripts describing the datasets. Information is included in the ReadMe files, which are provided in the Related URLs.

WNA-FLEXPART-BackTraj-2012 是2012年北美西部（Western North America, WNA）采用柔性粒子弥散模型（FLEXPART）生成的后向轨迹数据集。本产品的数据采集工作已全部完成。

利用拉格朗日粒子弥散模型（Lagrangian Particle Dispersion Model, LPDM）框架开展气团输送后向模拟，可建立源-受体关系（source-receptor relationships, SRRs），为分析不同地理区域与大气层结对下游观测的源贡献提供支撑。本研究选取的受体点位，匹配了1994-2021年间北美西部的网格化臭氧观测数据，观测来源涵盖臭氧探空仪、激光雷达、商用飞机采样以及专项飞机观测项目。针对每个受体点位，本研究采用以ERA5再分析数据驱动的柔性粒子弥散模型（FLEXPART），开展为期15天的后向源-受体关系计算，生成时间分辨率为逐小时、空间分辨率为1°×1°的全球模拟结果，模拟高度覆盖从地表至海拔20公里的范围。本数据集保留了每个受体点位的详细信息，包括网格化臭氧数值产品，可支持用户阐释并识别近30年来北美西部对流层内，不同垂直层级与时间尺度（如日循环、单日、季节、年内、年代际）下各类臭氧观测子集的源贡献。此外，若在本研究使用的部分或全部网格化臭氧受体的时空尺度范围内开展了其他配套原位观测，本模型数据集同样可用于支撑北美西部其他大气组分的源贡献分析。

本数据集的生成得到了美国国家航空航天局（NASA）大气成分航次数据分析与建模项目，以及通过埃姆斯研究中心美国国家航空航天局先进超级计算（NAS）分部实施的NASA高端计算（HEC）项目的资助（资助编号：SMD-20-28429430）。本研究衷心感谢众多独立研究团队采集的原位观测数据所发挥的关键作用，以及在模型开发与中间分析环节提供的相关贡献。

如需获取更多信息，请联系描述本数据集的论文作者。相关信息可参阅随附的自述文件（ReadMe），相关链接已在关联网址中提供。