Doppler Lidar Data Products Released for 2 ARM Campaigns

Published: 26 February 2025

The Atmospheric Radiation Measurement (ARM) User Facility operates Doppler lidars (DLs) at its fixed and mobile sites to provide height- and time-resolved measurements of radial velocity, attenuated aerosol backscatter, and signal-to-noise ratio. Radial velocity measurements from ARM DLs are used to derive profiles of horizontal winds from plan position indicator (PPI) scans and vertical velocity statistics from vertical staring data.

Value-added products (VAPs) providing horizontal wind profiles and vertical velocity statistics from DL data are now available for both the 2023–2024 Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) in La Jolla, California, and the ongoing Cloud And Precipitation Experiment at kennaook (CAPE-k) in northwestern Tasmania.

The Doppler Lidar Horizontal Wind Profiles (DLPROF-WIND) VAP produces daily files containing profiles of wind speed and direction. The Doppler Lidar Wind Statistics Profiles (DLPROF-WSTATS) VAP produces daily files containing height- and time-resolved estimates of vertical velocity variance, skewness (asymmetry), and kurtosis. DLPROF-WSTATS also estimates cloud properties from the vertically pointing measurements, including cloud base height and cloud base vertical velocity.

ARM deployed two DLs during EPCAPE, which ran from February 15, 2023, through February 14, 2024. One profiling system operated on the Ellen Browning Scripps Memorial Pier, and a scanning system operated on Mount Soledad, 3 kilometers from the pier. Availability of DLPROF-WIND and DLPROF-WSTATS from these sites is as follows:

• DLPROF-WIND at Scripps Pier: February 15, 2023, through February 13, 2024
• DLPROF-WSTATS at Scripps Pier: February 15, 2023, through February 14, 2024
• DLPROF-WIND at Mount Soledad: February 15, 2023, through February 14, 2024
• DLPROF-WSTATS at Mount Soledad: February 15, 2023, through February 12, 2024.

The Scripps Pier lidar executed wind profile scans once every 15 minutes and stared vertically the rest of the time. The Mount Soledad lidar executed wind profile scans once every 15 minutes, as well as periodic survey scans (PPI and range-height indicator) toward the north and west. As a result, the Scripps Pier lidar provided better temporal coverage for retrieval of vertical velocity statistics. Also, compared with the wind derived from the Mount Soledad lidar, the wind derived from the Scripps Pier lidar is likely to exhibit less error due to terrain-induced flow inhomogeneities. Thus, it is recommended to use the DLPROF-WIND and DLPROF-WSTATS data from Scripps Pier to obtain wind profiles and vertical velocity statistics, respectively, for EPCAPE.

For CAPE-k, only one profiling DL is deployed. That system is operating under the same scan schedule as the EPCAPE Scripps Pier lidar (i.e., wind profile scans every 15 minutes and vertical staring the rest of the time).

DLPROF-WIND and DLPROF-WSTATS are both available for CAPE-k from May 3, 2024, up to less than a week before the current date. The campaign is scheduled to end September 15, 2025.

More information about the VAPs can be found on the DLPROF-WIND and DLPROF-WSTATS web pages. Descriptions of algorithms used to generate the products, their input and output, and data quality control procedures are available in the DLPROF-WIND and DLPROF-WSTATS technical reports.

Access the DLPROF-WIND and DLPROF-WSTATS data in the ARM Data Center. (To download the data, first create an ARM account.)

For questions about these VAPs, please contact ARM translator Damao Zhang, ARM DL instrument mentor Rob Newsom, or VAP developer Gabriel Gibler.

To cite the DLPROF-WIND data, please use doi:10.5439/1178582. To cite the DLPROF-WSTATS data, please use doi:10.5439/1178583.