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The TAROGE-M observatory is an autonomous antenna array on the top of Mt. Melbourne (∼2700 m altitude) in Antarctica, designed to detect radio pulses from ultra-high energy (over 1017 eV) air showers coming from near-horizon directions. The targeted sources include cosmic rays, Earth-skimming tau neutrinos, and most of all, the anomalous near-horizon upward-going events of yet unknown origin discovered by ANITA experiments. The detection concept follows that of ANITA: monitoring large area of ice from high-altitude and taking advantage of strong geomagnetic field and quiet radio background in Antarctica, whereas having significantly greater livetime and scalability. The TAROGE-M station, upgraded from its prototype built in 2019, was deployed in January 2020, and consists of 6 log-periodic dipole antennas pointing horizontally with bandwidth of 180-450 MHz. The station is then calibrated with drone-borne transmitter, with which the event reconstruction obtained ∼0.3° angular resolution. The station was then smoothly operating in the following month, with the live time of ∼ 30 days, before interrupted by a power problem, and its online filtering has identified several candidate cosmic-ray events and sent out via satellite communication. In this paper, the instrumentation of the station for polar and high-altitude environment, its radio-locating performance, the preliminary result on cosmic-ray detection, and the future extension plan are presented.

TAROGE-M is a self-triggered radio antenna array atop the 2700 m high Mt.Melbourne in Antarctica, designed to detect impulsive geomagnetic emission fromextensive air showers induced by ultra-high energy (UHE) particles beyond 0.1EeV, including cosmic rays (CRs), Earth-skimming tau neutrinos, andparticularly, the "ANITA anomalous events" (AAEs) from near and below thehorizon, which origin remains uncertain and requires more experimental inputsfor clarification. The detection concept of TAROGE-M takes advantage of a high altitude withsynoptic view toward the horizon as an efficient signal collector, and theradio quietness as well as strong and near vertical geomagnetic field inAntarctica. This approach has a low energy threshold, high duty cycle, and iseasy to extend for quickly enlarging statistics. Here we report experimentalresults from the first TAROGE-M station deployed in 2020, corresponding to$25.3$-days of livetime. The station consists of six receiving antennasoperating at 180-450 MHz, and can reconstruct source directions with$\sim0.3^\circ$ angular resolution. To demonstrate its ability to detect UHEair showers, a search for CR signals in the data was conducted, resulting inseven identified events. These events have a mean reconstructed energy of$0.95_{-0.31}^{+0.46}$ EeV and zenith angles between $25^\circ-82^\circ$, withboth distributions agreeing with simulations. The estimated CR flux is alsoconsistent with results of other experiments. The TAROGE-M sensitivity to AAEsis approximated by the tau neutrino exposure with simulations, suggestingcomparable sensitivity as ANITA's at $~1$ EeV energy with a few station-yearsof operation. These first results verified the station design and performancein a polar and high-altitude environment, and are promising for furtherdiscovery of tau neutrinos and AAEs after an extension in the near future.

In 2016, a team of earth scientists directly engaged a team of computer scientists to identify cyberinfrastructure (CI) approaches that would speed up an earth science workflow. This paper describes the evolution of that workflow as the two teams bridged CI and an image segmentation algorithm to do large scale earth science research. The Pacific Research Platform (PRP) and The Cognitive Hardware and Software Ecosystem Community Infrastructure (CHASE-CI) resources were used to significantly decreased the earth science workflow's wall-clock time from 19.5 days to 53 minutes. The improvement in wall-clock time comes from the use of network appliances, improved image segmentation, deployment of a containerized workflow, and the increase in CI experience and training for the earth scientists. This paper presents a description of the evolving innovations used to improve the workflow, bottlenecks identified within each workflow version, and improvements made within each version of the workflow, over a three-year time period.

Radio-glaciological parameters from the Moore's Bay region of the Ross Ice Shelf, Antarctica, have been measured. The thickness of the ice shelf in Moore's Bay was measured from reflection times of radio-frequency pulses propagating vertically through the shelf and reflecting from the ocean, and is found to be 576± 8m. Introducing a baseline of 543 ±7m between radio transmitter and receiver allowed the computation of the basal reflection coefficient, R, separately from englacial loss. The depth-averaged attenuation length of the ice column, 〈L〉 is shown to depend linearly on frequency. The best fit (95% confidence level) is 〈L(v)〉 = (460± 20)-(180±40)vm (20 dB km-1), for the frequencies v = [0.100-0.850] GHz, assuming no reflection loss. The mean electric-field reflection coefficient is √R = 0.82 ±0.07 (1.7dB reflection loss) across [0.100-0.850] GHz, and is used to correct the attenuation length. Finally, the reflected power rotated into the orthogonal antenna polarization is