Breakout Summary Report

Desert-Urban SysTem IntegratEd Atmospheric Monsoon (DUSTIEAIM) is set to start on April 1 of 2026. DUSTIEAIM (pronounced “dusty-aim”) will study how the urban and desert environments influence convection and precipitation around Phoenix, especially in relation to the summertime North American Monsoon. The ARM Mobile Facility (AMF) 1 will operate for 18 months through the end of September 2027 with measurements at two sites with the main one located within the Phoenix metropolitan area. The campaign includes science objectives within topic areas landatmosphere interactions, aerosol processes and interactions with clouds and radiation, and precipitation processes.

Now is the time to get the community together to discuss how to best plan and execute DUSTIEAIM operations and measurements to meet our overall science objectives and to identify new opportunistic synergies with other measurements within the desert southwest. We expect to get feedback about the planned measurement strategies for process science and model improvement as well as to identify new synergies and interests from within the greater ARM/ASR community. This proposed session is relevant to the ARM/ASR community since DUSTIEAIM is an upcoming AMF campaign that aligns with ARM/ASR science and is likely to have future funding opportunities for measurements, e.g. Tethered Balloon Sonde (TBS) proposals, data analysis and model integration.

The Desert-Urban SysTem IntegratEd Atmospheric Monsoon (DUSTIEAIM) breakout session was organized into three presentation sections to engage the research community in discussions related to (1) modeling and forecasting needs, (2) measurement locations and strategies, and (3) coordinated intensive operational periods (IOPs). The goals were to receive input and discuss best operational practices, additional needs, and potential synergies. Below is a summary of each discussion session:

(1) Modeling and Forecasting: The need to constrain coarse-model dust, long-range transport, and longwave radiation for dust in models like E3SM was discussed and is included in the science plan. It was requested that the doppler lidar (DL) deployed allow for scanning to enable PPIs and RHIs to map out the wind structure of the boundary layer over Phoenix, as well as the need to launch additional radiosondes during the summer monsoons with preferably more than 2 per day over the full campaign since there are no operational radiosondes in Phoenix. Strong radiative effects of dust heating and cooling on the surface heat and winds has been detected in other locations and should be investigated for Phoenix. There was also a lot of discussion around whether observed dust storms and events for the area are most often associated with convection or synoptic transport, and what the impacts are for the different conditions that could be related to season with some having a greater chance for larger regional impacts via atmospheric transport of the plumes within the greater SW US. The ability to model and forecast such events would be advantageous to inform optimized sampling strategies.

(2) Measurement Locations and Strategies: The need to measure aerosol diurnal and seasonal cycles to understand source types and their roles regarding interannual variability and variability within each month was discussed for submicron and supermicron species. The guest instrument water isotope measurements that will be deployed by UNM/Galewsky will be connected with isotopic modeling efforts in E3SM and other global models such as the funded DOE EC project (1)   led by DUSTIEAIM co-PI Fiorella/LANL. Concerns about size-dependent biases in aerosol sampling were discussed. Some options to deal with this included optimizing the location of instruments within the ARM Aerosol Observing System (AOS) to minimize loss within sampling lines, sending additional coarse-mode measurements as well as designing new techniques to target sampling and minimize loss for larger particles. Particle transport, dust emissions, and impacts within the larger SW US including the Colorado Rockies snowpack was discussed in relation to the region of DUSTIEAIM being a potential major source of dust where DUSTIEAIM observations can be used for evaluation of models.

(3) Coordinated IOP’s and Science Plan: Summer and winter IOPs should be coordinated and include additional radiosonde launches at the main and/or supplementary site. Vertical profiling at the main site may be challenging due to congested airspace but should still be pursued for options using tethered balloon and/or UAVs north and northeast of the main site. Aircraft measurements would also be highly advantageous, but it was uncertain what options exist during DUSTIEAIM that might be available to fill this gap. The community agreed that organic aerosol formation and growth processes are largely understudied and have unique sources within the desert SW US that differ from the southeast US (e.g., BNF), warranting in-depth study and in situ observations.

• There was a lot of interest in the campaign from the ARM and ASR communities. We need to continue to reach out more to universities and other agencies to achieve collaborative science goals among the broader scientific community (see action items).

• It is recommended to have more time to facilitate discussion for coordinated scientific efforts at future meetings and/or during a workshop prior to the start of the campaign.

• Coordinated Intensive Operational Periods (IOP’s) currently being discussed included three periods: July - September 2026 (Summer 1), November 2026 - March 2027 (Winter), July - September 2027 (Summer 2). Detailed plans for operations within the IOPs were not finalized.

N/A

• Additional characterization of aerosol size distributions at the main and supplementary site that cover the coarse mode, such as can be made with an APS, open-path sensor, etc., and that could be located with the field measurements and/or adjacent to the ARM Aerosol Observing System (AOS), e.g. on the roof, when collocated with the AOS. It was suggested that alternative or new inlet systems could be tested/designed to target the larger modes. Filter-based aerosol samples would also be useful for single-particle analysis.

• Additional vertical profiling measurements are needed that could be challenging in this complex terrain. Ideas discussed that should be pursued further were tethered balloon sondes (TBS) - a TBS proposal is being submitted to the FY26 call - and UAVs like the ARM Arctic Shark. There was also interest in mapping the gradients between the metro and surrounding areas with mobile truck measurements like the BNL CMAS.

• The ability of a SACR to track dust events was mentioned based on previous measurements in Niamey, Niger. Cloud top height growth of convective clouds could be discerned from GOES. STEREOCAMs could also potentially characterize cloud top height growth of convective clouds but have a limited range that would not allow studies over the mountains.

• There was a variety of feedback on the radar siting and scanning with some support for the New River location in which a sector could be focused toward the south over the metro area or cells could be tracked that pass over the main AMF site. Much was left to be determined in terms of the measurement strategy. The location of the CSAPR2 radar will be selected by the end of March 2025 to facilitate an install date in September 2025 to include a six-month onsite testing period for the new radar before the official start of the campaign.

• Additional radiosonde launches are needed during the coordinated summer and winter IOPs. More discussion is needed to determine if the additional launches will be based on a standardized launch time or an event-based plan.

See Action Items

• Need to get an email list started for DUSTIEAIM to communicate and coordinate science.

• Work with ARM AOS mentors to develop measurement strategies to enable optimized sampling of dust and supermicron events.

• Plan for a pre-campaign workshop early next year.

• Coordinate community needs for guest instrument support.

• Identify potential vertical profiling capabilities, e.g. TBS and UAV, that can be located at the main and/or supplementary site to augment the AMF1 ground-based measurements.

• Connect with NOAA regarding forecasting needs to request mesoscale domain sectors for forecasted events which give 1-min data as has been done for campaigns in the past, e.g. CACTI.

• Coordinate with other communities, e.g. NASA EMIT science team, EarthCARE satellite science team, local universities, etc.