The Atmospheric Radiation Measurement (ARM) user facility’s Improved MICROBASE Product with Uncertainties (MICROBASEKAPLUS) is now available for the 2021–2022 TRacking Aerosol Convection interactions ExpeRiment (TRACER) near Houston, Texas.
MICROBASEKAPLUS is a value-added product (VAP) that provides continuous, high-time-resolution profiles of cloud microphysical properties such as liquid/ice water content and liquid/ice effective radius. The VAP was primarily developed for estimating radiative heating rate profiles, but scientists can use it for diverse applications, including evaluation of model cloud parameterizations, process-level studies of precipitation formation, and cloud particle phase partitioning.
MICROBASEKAPLUS uses parameterizations identical to those used by ARM’s historical Continuous Baseline Microphysical Retrieval (MICROBASE) VAP for determining the liquid/ice water content and liquid/ice effective radius. However, MICROBASEKAPLUS adds uncertainties to these quantities using a perturbation method first applied through the Atmospheric System Research (ASR) Quantifying Uncertainty in Cloud Retrievals (QUICR) science focus group (Zhao et al. 2014).
To determine the cloud microphysical properties, MICROBASEKAPLUS uses a combination of data from three VAPs: Ka-Band ARM Zenith Radar Active Remote Sensing of CLouds (KAZRARSCL), Interpolated Sonde (INTERPSONDE), and Microwave Radiometer Retrievals (MWRRET).
The MICROBASEKAPLUS product is archived as daily data files, with a time resolution of 4 seconds and vertical resolution of 0.03 kilometers up to a maximum height of 18 kilometers, which is consistent with the KAZRARSCL data resolutions.
MICROBASEKAPLUS evaluation data from October 1, 2021, through September 30, 2022, are available for the TRACER ARM Mobile Facility site in La Porte, Texas. Scientists can use these data now.
Ongoing work aims to use MICROBASEKAPLUS within the ARM Operational Ground-Based Retrieval Evaluation for Clouds (OGRE-CLOUDS) framework, evaluating improvements to cloud microphysics retrievals through radiative closure studies and comparing them with instrument simulator data. Through this process, the development team anticipates continuous improvement of the cloud microphysical estimates.
More information on MICROBASEKAPLUS is available on the VAP web page.
During this evaluation period, please send any product-related comments and suggestions to translator Dié Wang, principal investigator Michael Jensen, or data product developer Meng Wang. Such feedback will assist in improving the product before its full release.
Users can access the data set from the ARM Data Center. (To download the data, first create an ARM account.)
To cite the MICROBASEKAPLUS data, please use doi:10.5439/1768890.
# # #ARM is a DOE Office of Science user facility operated by nine DOE national laboratories.