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ARM's scanning cloud radars are fully coherent 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 (WSACR; 1.7 kW peak power) or X-band (XSACR; 20 kW peak power). At ARM's tropical sites, X-band radars are paired with the Ka-band because they are better suited for the atmospheric attenuation in this region. Beamwidth for the X-band is approximately 1 degree, and the Ka-band beamwidth is roughly 0.3 degrees. 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 XSACR uses range height indicator, or RHI, scans at numerous azimuths to obtain cloud volume data. For the second ARM Mobile Facility (AMF2), the XSACR can be dismounted from the pedestal it shares with the KASACR and mounted on a separate pedestal. This allows the XSACR to operate more like a weather (precipitation) radar in deployments where such local coverage is lacking. Measurements collected with the XSACR are copolar and cross-polar radar reflectivity, Doppler velocity, spectra width and spectra when not scanning, differential Reflectivity (Zdr), correlation coefficient (rho-hv), and specific differential phase (phi-dp). XSACR 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.

ARM的扫描云雷达（scanning cloud radars）是安装于统一扫描基座的全相干双频双偏振多普勒雷达。每座基座搭载一台Ka波段（Ka-band）雷达（峰值功率2kW），部署站点将决定其配套的另一台雷达为W波段（W-band，WSACR；峰值功率1.7kW）还是X波段（X-band，XSACR；峰值功率20kW）。在ARM的热带观测站点，X波段雷达会与Ka波段雷达配对部署，因其更适配该区域的大气衰减环境。X波段波束宽度约为1°，Ka波段波束宽度约为0.3°。由于天线波束宽度较窄，ARM扫描云雷达采用与典型天气雷达迥异的扫描策略：XSACR并未聚焦于平面位置指示（plan position indicator, PPI）扫描，而是在多个方位角上开展距离高度指示（range height indicator, RHI）扫描，以获取云体三维数据。对于第二代ARM移动设施（ARM Mobile Facility, AMF2），XSACR可从其与KASACR共用的基座上拆卸，并安装至独立基座，这使其可在缺乏本地覆盖的部署场景中，更贴近天气（降水）雷达的工作模式运行。XSACR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、谱宽以及非扫描状态下的频谱，差分反射率（differential Reflectivity, Zdr）、相关系数（correlation coefficient, ρ_hv）与特定差分相位（specific differential phase, φ_dp）。目前，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）野外观测实验的XSACR数据已以b1级产品形式发布。基于原始CACTI业务数据，b1级产品通过大量分析与校正实现了数据质量提升：该数据已完成交叉校准至统一基准，数据流针对实验期间出现的各类业务问题完成修正，并集成了多套数据质量掩码与基础衍生产品。更多详情可查阅《CACTI雷达b1级处理报告》。