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Michael J. Irvin

Abstract

Kites have been used as weather sensing solutions for over 250 years. The fact that they are simpler to operate and train on than alternative aerial systems, their ability to keep station at a fixed point for a long term, simplified altitude control, and the ease of retrieving their payload attribute to their growing appeal in atmospheric research. NASA, Toyota, and the School of Mechanical and Aerospace Engineering Oklahoma State University are active in developing and deploying high-altitude inflatable kite systems for atmospheric boundary layer (ABL) research—crucial to advancing the accuracy of weather forecasting. Improvements in kite design, as well as instrumentation and supporting infrastructure, are key to further accelerating the use of kites in atmospheric research. The work underway by these researchers is intended to be a deliberate step in the evolutionary development of these beneficial systems.

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I.-I. Lin, Robert F. Rogers, Hsiao-Ching Huang, Yi-Chun Liao, Derrick Herndon, Jin-Yi Yu, Ya-Ting Chang, Jun A. Zhang, Christina M. Patricola, Iam-Fei Pun, and Chun-Chi Lien

Abstract

Devastating Japan in October 2019, Supertyphoon (STY) Hagibis was an important typhoon in the history of the Pacific. A striking feature of Hagibis was its explosive RI (rapid intensification). In 24 h, Hagibis intensified by 100 kt, making it one of the fastest-intensifying typhoons ever observed. After RI, Hagibis’s intensification stalled. Using the current typhoon intensity record holder, i.e., STY Haiyan (2013), as a benchmark, this work explores the intensity evolution differences of these 2 high-impact STYs.

We found that the extremely high pre-storm sea surface temperature reaching 30.5°C, deep/warm pre-storm ocean heat content reaching 160 kJ cm−2, fast forward storm motion of ~8 ms−1, small during-storm ocean cooling effect of ~ 0.5C, significant thunderstorm activity at its center, and rapid eyewall contraction were all important contributors to Hagibis’s impressive intensification. There was 36% more air-sea flux for Hagibis’s RI than for Haiyan’s.

After its spectacular RI, Hagibis’s intensification stopped, despite favorable environments. Haiyan, by contrast, continued to intensify, reaching its record-breaking intensity of 170 kt. A key finding here is the multiple pathways that storm size affected the intensity evolution for both typhoons. After RI, Hagibis experienced a major size expansion, becoming the largest typhoon on record in the Pacific. This size enlargement, combined with a reduction in storm translational speed, induced stronger ocean cooling that reduced ocean flux and hindered intensification. The large storm size also contributed to slower eyewall replacement cycles (ERCs), which prolonged the negative impact of the ERC on intensification.

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Joshua Wurman, Karen Kosiba, Brian Pereira, Paul Robinson, Andrew Frambach, Alycia Gilliland, Trevor White, Josh Aikins, Robert J. Trapp, Stephen Nesbitt, Maiana N. Hanshaw, and Jon Lutz

Abstract

The Flexible Array of Radars and Mesonets (FARM) Facility is an extensive mobile/quickly-deployable (MQD) multiple-Doppler radar and in-situ instrumentation network.

The FARM includes four radars: two 3-cm dual-polarization, dual-frequency (DPDF), Doppler On Wheels DOW6/DOW7, the Rapid-Scan DOW (RSDOW), and a quickly-deployable (QD) DPDF 5-cm COW C-band On Wheels (COW).

The FARM includes 3 mobile mesonet (MM) vehicles with 3.5-m masts, an array of rugged QD weather stations (PODNET), QD weather stations deployed on infrastructure such as light/power poles (POLENET), four disdrometers, six MQD upper air sounding systems and a Mobile Operations and Repair Center (MORC).

The FARM serves a wide variety of research/educational uses. Components have deployed to >30 projects during 1995-2020 in the USA, Europe, and South America, obtaining pioneering observations of a myriad of small spatial and temporal scale phenomena including tornadoes, hurricanes, lake-effect snow storms, aircraft-affecting turbulence, convection initiation, microbursts, intense precipitation, boundary-layer structures and evolution, airborne hazardous substances, coastal storms, wildfires and wildfire suppression efforts, weather modification effects, and mountain/alpine winds and precipitation. The radars and other FARM systems support innovative educational efforts, deploying >40 times to universities/colleges, providing hands-on access to cutting-edge instrumentation for their students.

The FARM provides integrated multiple radar, mesonet, sounding, and related capabilities enabling diverse and robust coordinated sampling of three-dimensional vector winds, precipitation, and thermodynamics increasingly central to a wide range of mesoscale research.

Planned innovations include S-band On Wheels NETwork (SOWNET) and Bistatic Adaptable Radar Network (BARN), offering more qualitative improvements to the field project observational paradigm, providing broad, flexible, and inexpensive 10-cm radar coverage and vector windfield measurements.

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Stephen W. Nesbitt, Paola V. Salio, Eldo Ávila, Phillip Bitzer, Lawrence Carey, V. Chandrasekar, Wiebke Deierling, Francina Dominguez, Maria Eugenia Dillon, C. Marcelo Garcia, David Gochis, Steven Goodman, Deanna A. Hence, Karen A. Kosiba, Matthew R. Kumjian, Timothy Lang, Lorena Medina Luna, James Marquis, Robert Marshall, Lynn A. McMurdie, Ernani Lima Nascimento, Kristen L. Rasmussen, Rita Roberts, Angela K. Rowe, Juan José Ruiz, Eliah F.M.T. São Sabbas, A. Celeste Saulo, Russ S. Schumacher, Yanina Garcia Skabar, Luiz Augusto Toledo Machado, Robert J. Trapp, Adam Varble, James Wilson, Joshua Wurman, Edward J. Zipser, Ivan Arias, Hernán Bechis, and Maxwell A. Grover

Abstract

This article provides an overview of the experimental design, execution, education and public outreach, data collection, and initial scientific results from the Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign. RELAMPAGO was a major field campaign conducted in Córdoba and Mendoza provinces in Argentina, and western Rio Grande do Sul State in Brazil in 2018-2019 that involved more than 200 scientists and students from the US, Argentina, and Brazil. This campaign was motivated by the physical processes and societal impacts of deep convection that frequently initiates in this region, often along the complex terrain of the Sierras de Córdoba and Andes, and often grows rapidly upscale into dangerous storms that impact society. Observed storms during the experiment produced copious hail, intense flash flooding, extreme lightning flash rates and other unusual lightning phenomena, but few tornadoes. The 5 distinct scientific foci of RELAMPAGO: convection initiation, severe weather, upscale growth, hydrometeorology, and lightning and electrification are described, as are the deployment strategies to observe physical processes relevant to these foci. The campaign’s international cooperation, forecasting efforts, and mission planning strategies enabled a successful data collection effort. In addition, the legacy of RELAMPAGO in South America, including extensive multi-national education, public outreach, and social media data-gathering associated with the campaign, is summarized.

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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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Heidi Kreibich, Paul Hudson, and Bruno Merz

Abstract

Flood warning systems are longstanding success stories in respect to protecting human life, but monetary losses continue to grow. Knowledge on the effectiveness of flood early warning in reducing monetary losses is scarce, especially at the individual level. To gain more knowledge in this area, we analyze a dataset which is unique in respect to detailed information on warning reception and monetary losses at the property level and in respect to amount of data available. The dataset contains 4468 loss cases from six flood events in Germany. These floods occurred between 2002 and 2013. The data from each event was collected by computer aided telephone interviews in four surveys following a repeated cross-sectional design. We quantitatively reveal that flood early warning is only effective in reducing monetary losses when people know what to do when they receive the warning. We also show, that particularly long-term preparedness is associated with people knowing what to do when they receive a warning. Thus, risk communication, training, and (financial) support for private preparedness are effective in mitigating flood losses in two ways: through precautionary measures and more effective emergency responses.

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Adam C. Varble, Stephen W. Nesbitt, Paola Salio, Joseph C. Hardin, Nitin Bharadwaj, Paloma Borque, Paul J. DeMott, Zhe Feng, Thomas C. J. Hill, James N. Marquis, Alyssa Matthews, Fan Mei, Rusen Öktem, Vagner Castro, Lexie Goldberger, Alexis Hunzinger, Kevin R. Barry, Sonia M. Kreidenweis, Greg M. McFarquhar, Lynn A. McMurdie, Mikhail Pekour, Heath Powers, David M. Romps, Celeste Saulo, Beat Schmid, Jason M. Tomlinson, Susan C. van den Heever, Alla Zelenyuk, Zhixiao Zhang, and Edward J. Zipser

Abstract

The Cloud, Aerosol, and Complex Terrain Interactions (CACTI) field campaign was designed to improve understanding of orographic cloud life cycles in relation to surrounding atmospheric thermodynamic, flow, and aerosol conditions. The deployment to the Sierras de Córdoba range in north-central Argentina was chosen because of very frequent cumulus congestus, deep convection initiation, and mesoscale convective organization uniquely observable from a fixed site. The C-band Scanning Atmospheric Radiation Measurement (ARM) Precipitation Radar was deployed for the first time with over 50 ARM Mobile Facility atmospheric state, surface, aerosol, radiation, cloud, and precipitation instruments between October 2018 and April 2019. An intensive observing period (IOP) coincident with the RELAMPAGO field campaign was held between 1 November and 15 December during which 22 flights were performed by the ARM Gulfstream-1 aircraft.

A multitude of atmospheric processes and cloud conditions were observed over the 7-month campaign, including: numerous orographic cumulus and stratocumulus events; new particle formation and growth producing high aerosol concentrations; drizzle formation in fog and shallow liquid clouds; very low aerosol conditions following wet deposition in heavy rainfall; initiation of ice in congestus clouds across a range of temperatures; extreme deep convection reaching 21-km altitudes; and organization of intense, hail-containing supercells and mesoscale convective systems. These comprehensive datasets include many of the first ever collected in this region and provide new opportunities to study orographic cloud evolution and interactions with meteorological conditions, aerosols, surface conditions, and radiation in mountainous terrain.

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Graciela B. Raga, Luis A. Ladino, Darrel Baumgardner, Carolina Ramirez-Romero, Fernanda Córdoba, Harry Alvarez-Ospina, Daniel Rosas, Talib Amador, Javier Miranda, Irma Rosas, Alejandro Jaramillo, Jacqueline Yakobi-Hancock, Jong Sung Kim, Leticia Martínez, Eva Salinas, and Bernardo Figueroa

Abstract

Biomass burning (BB) emissions and African dust (AD) are often associated with poor regional air quality, particularly in the tropics. The Yucatan Peninsula is a fairly pristine site due to predominant trade winds, but occasionally BB and AD plumes severely degrade its air quality. The African Dust And Biomass Burning Over Yucatan (ADABBOY) project (Jan 2017- Aug 2018) was conducted in the Yucatan Peninsula to characterize physical and biological properties of particulate pollution at remote seaside and urban sites. The 18-month long project quantified the large interannual variability in frequency and spatial extent of BB and AD plumes. Remote and urban sites experienced air quality degradation under the influence of these plumes, with up to 200 and 300% increases in coarse particle mass under BB and AD influence, respectively. ADABBOY is the first project to systematically characterize elemental composition of airborne particles as a function of these sources and identify bioaerosol over Yucatan. Bacteria, actinobacteria (both continental and marine) and fungi propagules vary seasonally and interannually and revealed the presence of very different species and genera associated with different sources. A novel contribution of ADABBOY was the determination of the ice-nucleating abilities of particles emitted by different sources within an under-sampled region of the world. BB particles were found to be inefficient ice nucleating particles at temperatures warmer than -20°C, whereas both AD and background marine aerosol activated ice nucleating particles below -10°C.

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Bradley Wade Bishop, Ashley Marie Orehek, and Hannah R. Collier

Abstract

This study’s purpose is to capture the skills of Earth science data managers and librarians through interviews with current job holders. Job analysis interviews were conducted of fourteen participants –six librarians and eight data managers—to assess the types and frequencies of job tasks. Participants identified tasks related to communication, including collaboration, teaching, and project management activities. Data specific tasks included data discovery, processing, and curation, which require an understanding of the data, technology, and information infrastructures to support data use, re-use, and preservation. Most respondents had formal science education and six had a master’s degree in Library and Information Sciences. Most of the knowledge, skills, and abilities for these workers were acquired through on-the-job experience, but future professionals in these careers may benefit from tailored education informed through job analyses.

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Bing Pu and Qinjian Jin

Abstract

High concentrations of dust can affect climate and human health, yet our understanding of extreme dust events is still limited. A record-breaking trans-Atlantic African dust plume occurred during June 14–28, 2020, greatly degrading air quality over large areas of the Caribbean Basin and U.S. Daily PM2.5 concentrations exceeded 50 μg m−3 in several Gulf States, while the air quality index reached unhealthy levels for sensitive groups in more than 11 States. The magnitude and duration of aerosol optical depth over the tropical North Atlantic Ocean were the greatest ever observed during summer over the past 18 years based on satellite retrievals. This extreme trans-Atlantic dust event is associated with both enhanced dust emissions over western North Africa and atmospheric circulation extremes that favor long-range dust transport. An exceptionally strong African easterly jet and associated wave activities export African dust across the Atlantic toward the Caribbean in the middle to lower troposphere, while a westward extension of the North Atlantic subtropical high and a greatly intensified Caribbean low-level jet further transport the descended, shallower dust plume from the Caribbean Basin into the U.S. Over western North Africa, increased dust emissions are associated with strongly enhanced surface winds over dust source regions and reduced vegetation coverage in the western Sahel. While there are large uncertainties associated with assessing future trends in African dust emissions, model-projected atmospheric circulation changes in a warmer future generally favor increased long-range transport of African dust to the Caribbean Basin and the U.S.

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