Mid Latitudes | University of Wyoming Stratospheric Aerosol Measurements

The globally distributed stratospheric aerosol are a constant but highly variable component of the Earth’s atmosphere. They impact climate through their albedo and ozone through heterogeneous chemistry. For these reasons they must be considered in all climate prediction models, and there are a host of measurement platforms to characterize these aerosol. Their optical properties have been measured from satellites, since the late 1970s, while surface based lidar measurements have been completed regularly at a handful of locations since the mid 1970s. The first measurements, however, were completed using in situ instruments deployed on balloons and aircraft in the 1960s. In contrast to the satellite and lidar measurements which provide extinction or backscatter, the in situ measurements provide size distributions, and thus the only direct path for deriving the microphysical parameters required by the global models such as aerosol surface area, volume, and cross section. The longest continuous record of in situ stratospheric aerosol measurements has been completed at Laramie, Wyoming, 1971-2020, comprising nearly 400 individual balloon flights. The measurements from these flights since 1989 are contained in this digital archive. In addition to the flights from Laramie there are over 100 flights from McMurdo Station, Antarctica, 45 flights from Kiruna, Sweden, and a handful of flights from 13 other locations throughout the world stretching from 45˚S to 68˚N. The measurements from Laramie from 1971 – 1988 are available on the data base of the Network for the Detection of Atmospheric Composition Change, https://www.ndaccdemo.org/. This record includes the following <strong>Mid Latitudes</strong> datasets: /Aerosol_InSitu_Meas/US_Laramie_41N_105W_1989-2020/ /Aerosol_InSitu_Meas/US_Boulder_40N_105W_2019-/ /Aerosol_InSitu_Meas/FR_Gap_45N_6E_1996_1997/ /Aerosol_InSitu_Meas/FR_AirLaDour_44N_0W_1995/ /Aerosol_InSitu_Meas/AU_Mildura_34S_142E_1972-1980/ /Aerosol_InSitu_Meas/NZ_Lauder_45S_170E_1991-2001/ Within each of these directories are the following subdirectories/folders: Nr_Full_Profile - Sounding files for aerosol size and number concentration. The file name, e.g. 20080622_WY_WOPC_ATA6m.ASC, indicates the date (yyyymmdd) and location, MM=McMurdo, WY=Laramie, the instrument name (e.g. WOPC_ATA6m). The file extension indicates the vertical resolution, .ASC, implies full data , or an average, e.g. .500m for a 500 m average. These differences in the vertical averaging are separated into separate subfolders. The files include measurements from the surface to balloon burst. All files include general and specific metadata. For the Laramie measurements, where three different instruments (Dust, WOPC, WLPC) have been used, the measurements are further divided into instrument folders. SizeDist_Stratosphere - Lognormal size distributions (either unimodal or bimodal) at the vertical resolution indicated in the file name. The file names are somewhat long and include the name of the source file for the measurements, including the vertical resolution, the altitude at which the size distributions begin (typically the tropopause), and "_Srs_ce" which indicates the fit was completed with the new fitting algorithm which accounts for the instrument counting efficiency at each channel size. All files include general and specific metadata. For the Laramie measurements, where three different instruments (Dust, WOPC, WLPC) have been used, the measurements are further divided into instrument folders. IDL.SAV files are included in each folder for the Laramie measurements. Some folders contain post script files for quick looks at the data.全球分布的平流层气溶胶是地球大气中一类恒定但高度可变的组分。它们通过反照率（albedo）影响气候，通过非均相化学反应（heterogeneous chemistry）影响臭氧。正因如此，所有气候预测模型都必须将其纳入考量，目前已有大量测量平台可用于表征这类气溶胶。 自20世纪70年代末以来，科研人员已通过卫星对其光学特性开展测量；而自70年代中期起，全球少数站点已定期开展地基激光雷达（lidar）测量。不过，最早的平流层气溶胶测量是在20世纪60年代，通过搭载于气球和航空器的原位仪器（in situ instruments）完成的。 与卫星及激光雷达测量所提供的消光（extinction）或后向散射（backscatter）数据不同，原位测量可获取气溶胶的粒径分布（size distributions），因此是推导全球气候模型所需微物理参数（microphysical parameters，如气溶胶表面积、体积及截面积）的唯一直接途径。 目前最长的平流层气溶胶原位测量连续记录来自美国怀俄明州拉勒米（Laramie, Wyoming）站点，观测周期为1971年至2020年，累计完成近400次独立气球探测飞行。本数字档案收录了该站点1989年以来的探测数据。 除拉勒米站点外，本档案还包含南极麦克默多站（McMurdo Station）的100余次飞行探测数据、瑞典基律纳（Kiruna）的45次飞行探测数据，以及全球13个其他站点的少量探测数据，观测范围覆盖南纬45°至北纬68°。1971年至1988年的拉勒米站点测量数据可通过大气成分变化检测网络（Network for the Detection of Atmospheric Composition Change, NDACC）数据库获取，链接为：https://www.ndaccdemo.org/。 本记录包含以下<strong>中纬度</strong>数据集： /Aerosol_InSitu_Meas/US_Laramie_41N_105W_1989-2020/ /Aerosol_InSitu_Meas/US_Boulder_40N_105W_2019- /Aerosol_InSitu_Meas/FR_Gap_45N_6E_1996_1997/ /Aerosol_InSitu_Meas/FR_AirLaDour_44N_0W_1995/ /Aerosol_InSitu_Meas/AU_Mildura_34S_142E_1972-1980/ /Aerosol_InSitu_Meas/NZ_Lauder_45S_170E_1991-2001/ 每个数据集目录下均包含以下子目录/文件夹： 1. Nr_Full_Profile：用于获取气溶胶粒径与数浓度的探空文件。文件名示例：20080622_WY_WOPC_ATA6m.ASC，其中日期格式为yyyymmdd，地点代码（MM=麦克默多，WY=拉勒米），仪器名称（如WOPC_ATA6m）。文件扩展名代表垂直分辨率：.ASC表示完整数据，.500m则代表500米平均数据。垂直平均的差异被划分至不同子文件夹中。所有文件均覆盖从地表至气球爆裂高度的测量数据，且包含通用与专属元数据（metadata）。针对拉勒米站点的测量，由于曾使用Dust、WOPC、WLPC三种不同仪器，数据还会进一步按仪器划分子文件夹。 2. SizeDist_Stratosphere：以文件名中指定的垂直分辨率存储的对数正态粒径分布（单峰或双峰分布）。文件名较长，包含测量源文件名称（含垂直分辨率）、粒径分布起始高度（通常为对流层顶），以及后缀“_Srs_ce”，代表本次拟合采用了可校正各通道仪器计数效率的新型拟合算法。所有文件均包含通用与专属元数据。针对拉勒米站点的测量，数据同样会按仪器划分子文件夹，且每个文件夹均附带IDL .SAV格式文件。部分文件夹还包含用于快速预览数据的PostScript文件。