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  • Author or Editor: Sonia Lasher-Trapp x
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Kathleen Quardokus
,
Sonia Lasher-Trapp
, and
Eric M. Riggs

Participating in scientific research as an undergraduate student provides an opportunity to increase understanding of how scientific knowledge is advanced, to learn new research tools, to develop the ability to critically analyze new ideas, and to practice disseminating scientific findings. This experience unfortunately has traditionally been limited to students that can participate in select programs (e.g., summer research experiences, undergraduate positions in a faculty member's research group, special topics courses, independent study, or internships).

A new laboratory course has been developed to provide sophomore- level atmospheric science students with the opportunity to participate in an authentic research project within the structure of an academic semester. The course consists of two modules based upon research topics currently under investigation by faculty (here, specific problems in cloud microphysics and severe weather research). Students participate in learning activities, work as a research team, and formally present research findings. Phenomenological evaluation of the new course through interviews, surveys, and student performance assessments, using constant comparative analysis, suggests these students improve their ability to understand and perform authentic research. The students attribute their success to the “scaffolding” structure of the course, peer collaboration, and their own high level of enthusiasm. Results also imply that students gain some clarification of their career options.

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Sonia Lasher-Trapp
,
Sophie A. Orendorf
, and
Robert J. Trapp

Abstract

Derechos are extensive swaths of damaging winds produced by some long-lived, widespread mesoscale convective systems. Little research has been conducted concerning how derecho mechanisms might change in a future, warmer climate. In this study, the pseudo–global warming method is utilized to evaluate how the 10 August 2020 midwestern U.S. derecho, the costliest thunderstorm event in U.S. history to date, might differ if it instead occurred in a warmer climate at the end of this century. The 10 August derecho event is first simulated in its observed environment, and then resimulated in environments altered according to projections from different climate models using a high-emissions climate change scenario. Results suggest that near the end of this century, a similar derecho event may not necessarily have more intense winds but could possibly impact a geographical area 50% to 100% larger. The physical chain of events leading to this greater geographical impact result from the derecho winds beginning earlier in the storm lifetime, due to increased precipitation combined with decreased relative humidity right above the ground, and derecho winds extending northward due to a strengthening of the parent storm from increased instability there. All these factors enhance the area of evaporative cooling and thus the cold pool, which in turn extends the area covered by the rear-inflow jet within the storm, the likely main mechanism for most of the damaging winds at the ground in the historical event. More study of other cases is required to evaluate the generality of this result.

Open access
Loran Carleton Parker
,
Gerald H. Krockover
,
Sonia Lasher-Trapp
, and
David C. Eichinger

Learning about the nature of science involves learning about science, its goals, methods, products, and practitioners. As university students progress through their studies, what are they learning about science? Several studies have attempted to answer this question, but none have examined the ideas of atmospheric science students. We discuss the results of a single study that explores introductory undergraduate atmospheric science students' ideas about the nature of science, and examines relationships between these ideas and students' previous university science coursework. We focus on the ideas about the definition of science, about scientific knowledge, about the scientific process, and about the scientific enterprise held by a group of undergraduate atmospheric science students. Unlike previous university students studied, the majority of these students viewed science as an enterprise that requires creativity and imagination. They also believed science to be a discipline that “proves” its assertions by subjecting them to a series of confirming “tests” through which scientific knowledge travels upward in a hierarchy of proof from the status of “theory” to “law.” This understanding about the nature of science is divergent from the nature of science as described by many philosophers, scientists, and science educators. We discuss the possible implications of these results for scientists and science educators, and urge them to open dialogs about the nature of science with their own students, as well as the general public.

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Loran Carleton Parker
,
Gerald H. Krockover
,
Sonia Lasher-Trapp
, and
David C. Eichinger
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Lulin Xue
,
Sudarsan Bera
,
Sisi Chen
,
Harish Choudhary
,
Shivsai Dixit
,
Wojciech W. Grabowski
,
Sandeep Jayakumar
,
Steven Krueger
,
Gayatri Kulkarni
,
Sonia Lasher-Trapp
,
Holly Mallinson
,
Thara Prabhakaran
, and
Shin-ichiro Shima
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David C. Leon
,
Jeffrey R. French
,
Sonia Lasher-Trapp
,
Alan M. Blyth
,
Steven J. Abel
,
Susan Ballard
,
Andrew Barrett
,
Lindsay J. Bennett
,
Keith Bower
,
Barbara Brooks
,
Phil Brown
,
Cristina Charlton-Perez
,
Thomas Choularton
,
Peter Clark
,
Chris Collier
,
Jonathan Crosier
,
Zhiqiang Cui
,
Seonaid Dey
,
David Dufton
,
Chloe Eagle
,
Michael J. Flynn
,
Martin Gallagher
,
Carol Halliwell
,
Kirsty Hanley
,
Lee Hawkness-Smith
,
Yahui Huang
,
Graeme Kelly
,
Malcolm Kitchen
,
Alexei Korolev
,
Humphrey Lean
,
Zixia Liu
,
John Marsham
,
Daniel Moser
,
John Nicol
,
Emily G. Norton
,
David Plummer
,
Jeremy Price
,
Hugo Ricketts
,
Nigel Roberts
,
Phil D. Rosenberg
,
David Simonin
,
Jonathan W. Taylor
,
Robert Warren
,
Paul I. Williams
, and
Gillian Young

Abstract

The Convective Precipitation Experiment (COPE) was a joint U.K.–U.S. field campaign held during the summer of 2013 in the southwest peninsula of England, designed to study convective clouds that produce heavy rain leading to flash floods. The clouds form along convergence lines that develop regularly as a result of the topography. Major flash floods have occurred in the past, most famously at Boscastle in 2004. It has been suggested that much of the rain was produced by warm rain processes, similar to some flash floods that have occurred in the United States. The overarching goal of COPE is to improve quantitative convective precipitation forecasting by understanding the interactions of the cloud microphysics and dynamics and thereby to improve numerical weather prediction (NWP) model skill for forecasts of flash floods. Two research aircraft, the University of Wyoming King Air and the U.K. BAe 146, obtained detailed in situ and remote sensing measurements in, around, and below storms on several days. A new fast-scanning X-band dual-polarization Doppler radar made 360° volume scans over 10 elevation angles approximately every 5 min and was augmented by two Met Office C-band radars and the Chilbolton S-band radar. Detailed aerosol measurements were made on the aircraft and on the ground. This paper i) provides an overview of the COPE field campaign and the resulting dataset, ii) presents examples of heavy convective rainfall in clouds containing ice and also in relatively shallow clouds through the warm rain process alone, and iii) explains how COPE data will be used to improve high-resolution NWP models for operational use.

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Greg M. McFarquhar
,
Christopher S. Bretherton
,
Roger Marchand
,
Alain Protat
,
Paul J. DeMott
,
Simon P. Alexander
,
Greg C. Roberts
,
Cynthia H. Twohy
,
Darin Toohey
,
Steve Siems
,
Yi Huang
,
Robert Wood
,
Robert M. Rauber
,
Sonia Lasher-Trapp
,
Jorgen Jensen
,
Jeffrey L. Stith
,
Jay Mace
,
Junshik Um
,
Emma Järvinen
,
Martin Schnaiter
,
Andrew Gettelman
,
Kevin J. Sanchez
,
Christina S. McCluskey
,
Lynn M. Russell
,
Isabel L. McCoy
,
Rachel L. Atlas
,
Charles G. Bardeen
,
Kathryn A. Moore
,
Thomas C. J. Hill
,
Ruhi S. Humphries
,
Melita D. Keywood
,
Zoran Ristovski
,
Luke Cravigan
,
Robyn Schofield
,
Chris Fairall
,
Marc D. Mallet
,
Sonia M. Kreidenweis
,
Bryan Rainwater
,
John D’Alessandro
,
Yang Wang
,
Wei Wu
,
Georges Saliba
,
Ezra J. T. Levin
,
Saisai Ding
,
Francisco Lang
,
Son C. H. Truong
,
Cory Wolff
,
Julie Haggerty
,
Mike J. Harvey
,
Andrew R. Klekociuk
, and
Adrian McDonald

Abstract

Weather and climate models are challenged by uncertainties and biases in simulating Southern Ocean (SO) radiative fluxes that trace to a poor understanding of cloud, aerosol, precipitation, and radiative processes, and their interactions. Projects between 2016 and 2018 used in situ probes, radar, lidar, and other instruments to make comprehensive measurements of thermodynamics, surface radiation, cloud, precipitation, aerosol, cloud condensation nuclei (CCN), and ice nucleating particles over the SO cold waters, and in ubiquitous liquid and mixed-phase clouds common to this pristine environment. Data including soundings were collected from the NSF–NCAR G-V aircraft flying north–south gradients south of Tasmania, at Macquarie Island, and on the R/V Investigator and RSV Aurora Australis. Synergistically these data characterize boundary layer and free troposphere environmental properties, and represent the most comprehensive data of this type available south of the oceanic polar front, in the cold sector of SO cyclones, and across seasons. Results show largely pristine environments with numerous small and few large aerosols above cloud, suggesting new particle formation and limited long-range transport from continents, high variability in CCN and cloud droplet concentrations, and ubiquitous supercooled water in thin, multilayered clouds, often with small-scale generating cells near cloud top. These observations demonstrate how cloud properties depend on aerosols while highlighting the importance of dynamics and turbulence that likely drive heterogeneity of cloud phase. Satellite retrievals confirmed low clouds were responsible for radiation biases. The combination of models and observations is examining how aerosols and meteorology couple to control SO water and energy budgets.

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