The PBL Moving Active Profiling System (PBLMAPS)

Due to the high cost of airborne field campaigns, the deployment of the MARLi and ADL on the UWKA and C-130/G-V is limited to a short period per year.  Furthermore, there are conditions where airborne measurements are not feasible, such as near convective storms due to turbulence and lighting. To effectively use the MARLi and ADL on the ground, we developed the PBLMAPS by integrating the MARLi with ADL and other instruments in a cargo van (see Fig. 1). The PBLMAPS uses a low-roof four-wheel-drive FORD TRANSIT cargo van as the mobile platform. MARLi is mounted inside the van operating through a roof hatch with a 17-inch optical window. A single-beam ADL is mounted on the top of the van roof near the MARLi optical window to provide collocated vertical velocity measurements. Space is reserved to install the other four ADL beams to provide horizontal wind measurements in the future.  The same suite of weather instruments as the NOAA/NSSL mobile mesonet is mounted to a custom-designed rack above the hood to go along with a computer inside.  The road test of the PBLMAPS operation was done in the summer of 2023.

The synergy of the MARLi and ADL measurements offers improved PBL characterizing capabilities. First, the sensible and latent heat fluxes can be estimated by combining vertical velocity measurements with vertical water vapor and temperature measurements, (Rao et al. 2002; Kiemle et al. 2007; Wulfmeyer et al. 2015).   Second, combining MARLi 355nm aerosol extinction and backscattering coefficients with ADL 1550 nm backscattering coefficients could improve aerosol size/type characterizations.

Fig. 1 FORD TRANSIT cargo van modified to carry MARLi and zenith pointing ADL: (a)MARLi inside the van, (b) showing a power generator on a cargo carrier and window hatch, and (c) ADL on the top.

The design goal of the PBLMAPS is uninterrupted operations while driving under safe-weather conditions. Generators mounted on a cargo carrier will provide needed electric power for operations. Thus, the PBLMAPS can be deployed to where processes happen with road access and can move quickly as needed, such as observing the inflow structures of tornadic storms. The actual operation modes will depend on the requirements of measurement resolution and accuracy, PBL structure, and road conditions. Therefore, as discussed below, the PBLMAPS could be deployed to meet many critical measurement needs to complement their measurements from the UWKA, C-130, and G-V.