kasacrcrcal (a1)

The Ka-Band Scanning ARM Cloud Radar (KASACR) records cloud properties. ARM's scanning cloud radars are dual-frequency, dual-polarization Doppler radars mounted on a common scanning pedestal. Each pedestal includes a Ka-band radar (2kW peak power) and the deployment location determines whether the second radar is a W-band (1.7 kW peak power) or an X-band (20 kW peak power). Beamwidths for Ka-bands paired with W-bands are roughly matched at 0.3 degrees. The X-band beamwidth is approximately 1 degree. Due to the narrow antenna beamwidth, ARM’s scanning cloud radars use scanning strategies unlike typical weather radars. Rather than focusing on plan position indicator, or PPI, scans, the KASACR uses range height indicator, or RHI, scans at numerous azimuths to obtain cloud volume data. Measurements collected with the KASACR are copolar and cross-polar radar reflectivity, Doppler velocity, spectra width and spectra when not scanning, and linear depolarization ratio. KASACR data from the 2018–2019 Cloud, Aerosol, and Complex Terrain Interactions (CACTI) field campaign in Argentina are now available as b1-level products. Building on the original CACTI operational data, the b1-level products feature improved data quality resulting from extensive analyses and corrections. The data are cross-calibrated to a common point, datastreams are corrected for operational issues that occurred during the campaign, and several data quality masks and basic derived products are incorporated. For more information, read the CACTI radar b1-level processing report.

Ka波段扫描ARM云雷达（Ka-Band Scanning ARM Cloud Radar，KASACR）用于记录云系特性参数。ARM旗下的扫描型云雷达均为搭载于共用扫描转台的双频双极化多普勒雷达。每套转台均配备一台Ka波段雷达（峰值功率2kW），第二台雷达的频段由部署场地决定：可为W波段（峰值功率1.7kW）或X波段（峰值功率20kW）。与W波段配对的Ka波段波束宽度约为0.3°，二者波束宽度大致匹配；X波段波束宽度则约为1°。由于天线波束宽度极窄，ARM的扫描型云雷达采用了与常规天气雷达不同的扫描策略。KASACR并未聚焦于平面位置显示器（PPI）扫描模式，而是通过在多个方位角下执行距离高度显示器（RHI）扫描，以获取云体三维体积数据。该设备采集的测量参数包括同极化与交叉极化雷达反射率、多普勒速度、频谱宽度、非扫描状态下的雷达频谱，以及线性退极化比。2018—2019年在阿根廷开展的云、气溶胶与复杂地形相互作用（Cloud, Aerosol, and Complex Terrain Interactions，CACTI）外场试验所获取的KASACR数据，现已以b1级产品形式发布。相较于原始CACTI业务数据，b1级产品通过全面的分析与校正流程提升了数据质量：包括将多源数据交叉定标至统一基准点、针对试验期间出现的业务运行问题校正数据流，同时集成了多套数据质量掩码及基础衍生产品。更多详细信息可参阅《CACTI雷达b1级处理报告》。