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James E. Jordan, David L. Marcotte, and G. W. K. Moore

Abstract

This paper describes the development of a novel airborne system that receives a real-time imagery broadcast in the Automatic Picture Transmission (APT) format from polar-orbiting weather satellites. The availability of such real-time imagery allows for the possibility of redirecting an aircraft measurement platform to sample an area of the atmosphere in a timely and spatially meaningful fashion. This technology could also provide pilots with new and potentially important information that could be used to reroute aircraft around weather systems. The authors are not aware of any other airborne APT imaging system that has been documented in the open literature.

The system described in this paper has been used in a number of meteorological field experiments, and imagery obtained during these experiments is presented to illustrate the capabilities of the system.

The most critical element for an airborne system is the antenna due to the conflicting requirements imposed by the wavelength, which is greater than 2 m, and aerodynamic–structural considerations favoring the smallest possible size. The authors describe a low-profile “electrically small” 40-cm-square patch antenna developed for this system that provides excellent gain for elevation angles over 25°.

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Allen B. White, James R. Jordan, Brooks E. Martner, F. Martin Ralph, and Bruce W. Bartram

Abstract

A new S-band vertical profiler with a coupler option for extending the dynamic range of the radar’s receiver is discussed. The added dynamic range allows the profiler to record radar reflectivity measurements in moderate to heavy precipitation that otherwise would not have been possible with this system because of receiver saturation. The radar hardware, signal processor, and operating software are based on existing S-band and UHF profiler technology. Results from a side-by-side comparison with a calibrated Ka-band radar are used to determine the calibration and sensitivity of the S-band profiler. In a typical cloud profiling mode of operation, the sensitivity is −14 dBZ at 10 km. Examples taken from a recent field campaign are shown to illustrate the profiler’s ability to measure vertical velocity and radar reflectivity profiles in clouds and precipitation, with particular emphasis on the benefit provided by the coupler technology.

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Clay S. Tucker, Jill C. Trepanier, Pamela B. Blanchard, Ed Bush, James W. Jordan, Mark J. Shafer, and John Andrew Nyman

Abstract

Environmental education is key in solving environmental problems and for producing a future workforce capable of solving issues of climate change. Over the last two decades, the Coastal Roots Program at Louisiana State University (LSU) has reached more than 26,676 K-12 students in Louisiana to teach them environmental science and has brought them to restoration sites to plant 194,336 school-grown trees and grasses. The co-directors of Coastal Roots are continually searching for opportunities to enrich the experience of teachers and students in connecting school subjects, Coastal Roots, and stewardship. In school year 2018–2019, students in five local schools entered a pilot program to learn how tree-ring science informs environmental science broadly. During their scheduled restoration planting trips, students were asked to collect the following tree data: tree cores, tree height, tree diameter, tree species, and global positioning system location points. Datawere given to scientists atLSUfor preliminary analysis, and graphical representation of the data were shown to the students for their interpretation. Results from this program indicate that bringing students into the field and teaching them a newscientific skill improved their understanding of environmental science and their role in coastal restoration, and tree-ring data showed significant correlations to various climate parameters in Louisiana. Additionally, we find that bringing this knowledge to teachers allows the knowledge to spread for multiple generations of students. Here we present tree-ring data from this project, lessons learned during the pilot program, advantages to student-based citizen science, and recommendations for similar programs.

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Eric J. Jensen, Leonhard Pfister, David E. Jordan, Thaopaul V. Bui, Rei Ueyama, Hanwant B. Singh, Troy D. Thornberry, Andrew W. Rollins, Ru-Shan Gao, David W. Fahey, Karen H. Rosenlof, James W. Elkins, Glenn S. Diskin, Joshua P. DiGangi, R. Paul Lawson, Sarah Woods, Elliot L. Atlas, Maria A. Navarro Rodriguez, Steven C. Wofsy, Jasna Pittman, Charles G. Bardeen, Owen B. Toon, Bruce C. Kindel, Paul A. Newman, Matthew J. McGill, Dennis L. Hlavka, Leslie R. Lait, Mark R. Schoeberl, John W. Bergman, Henry B. Selkirk, M. Joan Alexander, Ji-Eun Kim, Boon H. Lim, Jochen Stutz, and Klaus Pfeilsticker

Abstract

The February–March 2014 deployment of the National Aeronautics and Space Administration (NASA) Airborne Tropical Tropopause Experiment (ATTREX) provided unique in situ measurements in the western Pacific tropical tropopause layer (TTL). Six flights were conducted from Guam with the long-range, high-altitude, unmanned Global Hawk aircraft. The ATTREX Global Hawk payload provided measurements of water vapor, meteorological conditions, cloud properties, tracer and chemical radical concentrations, and radiative fluxes. The campaign was partially coincident with the Convective Transport of Active Species in the Tropics (CONTRAST) and the Coordinated Airborne Studies in the Tropics (CAST) airborne campaigns based in Guam using lower-altitude aircraft (see companion articles in this issue). The ATTREX dataset is being used for investigations of TTL cloud, transport, dynamical, and chemical processes, as well as for evaluation and improvement of global-model representations of TTL processes. The ATTREX data are publicly available online (at https://espoarchive.nasa.gov/).

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Britton B. Stephens, Matthew C. Long, Ralph F. Keeling, Eric A. Kort, Colm Sweeney, Eric C. Apel, Elliot L. Atlas, Stuart Beaton, Jonathan D. Bent, Nicola J. Blake, James F. Bresch, Joanna Casey, Bruce C. Daube, Minghui Diao, Ernesto Diaz, Heidi Dierssen, Valeria Donets, Bo-Cai Gao, Michelle Gierach, Robert Green, Justin Haag, Matthew Hayman, Alan J. Hills, Martín S. Hoecker-Martínez, Shawn B. Honomichl, Rebecca S. Hornbrook, Jorgen B. Jensen, Rong-Rong Li, Ian McCubbin, Kathryn McKain, Eric J. Morgan, Scott Nolte, Jordan G. Powers, Bryan Rainwater, Kaylan Randolph, Mike Reeves, Sue M. Schauffler, Katherine Smith, Mackenzie Smith, Jeff Stith, Gregory Stossmeister, Darin W. Toohey, and Andrew S. Watt

Abstract

The Southern Ocean plays a critical role in the global climate system by mediating atmosphere–ocean partitioning of heat and carbon dioxide. However, Earth system models are demonstrably deficient in the Southern Ocean, leading to large uncertainties in future air–sea CO2 flux projections under climate warming and incomplete interpretations of natural variability on interannual to geologic time scales. Here, we describe a recent aircraft observational campaign, the O2/N2 Ratio and CO2 Airborne Southern Ocean (ORCAS) study, which collected measurements over the Southern Ocean during January and February 2016. The primary research objective of the ORCAS campaign was to improve observational constraints on the seasonal exchange of atmospheric carbon dioxide and oxygen with the Southern Ocean. The campaign also included measurements of anthropogenic and marine biogenic reactive gases; high-resolution, hyperspectral ocean color imaging of the ocean surface; and microphysical data relevant for understanding and modeling cloud processes. In each of these components of the ORCAS project, the campaign has significantly expanded the amount of observational data available for this remote region. Ongoing research based on these observations will contribute to advancing our understanding of this climatically important system across a range of topics including carbon cycling, atmospheric chemistry and transport, and cloud physics. This article presents an overview of the scientific and methodological aspects of the ORCAS project and highlights early findings.

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