ACT for Science: Use New Features in Open-Source Toolkit

Published: 23 September 2022

The graphic shows the mean of co_2 flux (umol/m^2s)) by wind_direction_from_north from January 1 to December 31, 2021. The mean extends from -4.5 to 4.5. Crop types shown are developed/low intensity, grass/pasture, and winter wheat.
Figure 1: A new ACT plotting routine produced this plot of the mean CO₂ flux from the Southern Great Plains E14 ECOR system based on wind direction and speed for 2021. Crop type pulled from the U.S. Department of Agriculture CropScape web service using ACT is overlaid.

The Atmospheric data Community Toolkit (ACT) regularly adds new features. We will highlight a number of these on the “ACT for Science” poster led by Zachary Sherman at October’s Joint ARM User Facility/Atmospheric System Research (ASR) Principal Investigators (PI) Meeting, but here’s a look at some of the latest features included with the recent release of version 1.2.0.

Data Roses

Wind roses show the distribution of wind speed and direction, but a new plotting routine in ACT can display the distribution of data based on wind direction and speed.

The example in Figure 1 shows the mean CO₂ flux based on wind direction and speed for all the 2021 eddy correlation (ECOR) flux measurement system data at the Southern Great Plains extended facility E14 near Lamont, Oklahoma. In this example, crop type is easily overlaid after pulling the information from the U.S. Department of Agriculture CropScape web service, for which ACT has a function.

Additional examples and options can be found on our recently updated documentation page.

Enabling Easier Access to Other Organizations’ Data

The second ARM Mobile Facility is deployed near Crested Butte, Colorado, in support of the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign. Similarly, NOAA has instrumentation deployed in the same region in support of the Study of Precipitation, the Lower Atmosphere and Surface for Hydrometeorology (SPLASH).

In addition, as ARM prepares to deploy the third ARM Mobile Facility to northern Alabama, there are NOAA assets in the region that can benefit research by ARM users.

Data products from NOAA and ARM are in different formats, and it takes added effort to work with data from both organizations. Recent code additions to ACT make it easy to download data from the NOAA Physical Science Laboratory’s FTP site and read it into an Xarray data set, which is used throughout all of ACT’s functions. Currently, the read capability is limited to the Parsivel disdrometer, surface meteorology system, radar wind profiler, and frequency-modulated continuous wave (FMCW) radars (Figure 2), but is expected to expand to more instruments.

Three plots are vertically stacked to show different radar reflectivities from -40 to 40 dbZ up to 10,000 meters.
Figure 2: ACT enables users to work with data from concurrent ARM and NOAA campaigns near Crested Butte, Colorado. These plots for August 15, 2022, show Ka-Band ARM Zenith Radar (KAZR) reflectivity (top) from the Gothic site; NOAA uncalibrated FMCW radar reflectivity from the Kettle Ponds site (middle); and NOAA uncalibrated FMCW radar reflectivity (bottom) from the Bush Creek site.

Greater ARM Aerial Facility Support

The second ACT roadmap states that increasing the offerings available in ACT for aerial data will be beneficial, and it’s listed as a high priority. This comes in preparation for continued flights of ARM’s ArcticShark uncrewed aerial system and for the new crewed research aircraft (currently undergoing modifications) to come online in the future.

The ability to read ICARTT-formatted files was recently added to ACT (Figure 3). These ICARTT files are available through ARM’s Data Discovery when downloading ARM Aerial Facility data in ASCII format. This capability requires the installation of an existing library (icartt) developed and maintained by researchers from the University of Augsburg.

A full example of how easy it is to read ICARTT data and plot using ACT is available here.

Dewpoint temperature and static pressure data show dips between 15:00 and 15:30 UTC and right before 16:30 UTC.
Figure 3: ARM Aerial Facility pressure and temperature data from November 4, 2018, flights around Córdoba, Argentina. ACT was used to read the ICARTT-formatted data into an Xarray object, which can then be used with ACT’s functions for plotting.

ACT in Action

Nine University of Washington students traveled to Richland, Washington, to take a two-week instrumentation short course taught by scientists and engineers, many of them ARM instrument mentors, at Pacific Northwest National Laboratory. The course took place from September 12 to 22.

Focusing on themes such as calibration and accuracy, instructors developed lectures on ground and airborne instrumentation and measurements, data management, and atmospheric chemistry and cloud microphysics.

There’s a lot more in ACT that’s been added recently and more planned, so please go check out the documentation and example pages for more information on ACT, and don’t forget to stop by our poster at the PI meeting!

University of Washington professor Lynn McMurdie and PNNL earth scientist Lexie Goldberger co-organized the course. Instructors augmented lectures through experiments, demonstrations, mock field campaign designs, field trips, and computer analyses (including a short introduction to ACT and how it can be used to visualize data).

An introduction to ACT and how it can be used to enable open science will also be covered during a Python workshop, led by Maxwell Grover of Argonne National Laboratory, at the Midwest Student Conference on Atmospheric Research (MSCAR) in October. MSCAR is an event hosted by graduate students at the University of Illinois Urbana-Champaign, The workshop will detail how to use ACT as well as other open-source packages, such as the Python ARM Radar Toolkit (Py-ART).

At the American Meteorological Society (AMS) Annual Meeting in January 2023, an ARM team will teach a short course detailing how to use ACT and other open-source tools to work with SAIL measurements. The short course will detail how to use ACT and other ARM toolkits to analyze different data sets from the campaign, including precipitation, radiation, and hydrological measurements. Registration details will be made available soon.

There’s a lot more in ACT that’s been added recently and more planned, so please go check out the documentation and example pages for more information on ACT, and don’t forget to stop by our poster at the PI meeting!

–ACT Team