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  • Author or Editor: Zachary J. Lebo x
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Matthew R. Kumjian
,
Kevin A. Bowley
,
Paul M. Markowski
,
Kelly Lombardo
,
Zachary J. Lebo
, and
Pavlos Kollias
Full access
Matthew R. Kumjian
,
Kevin A. Bowley
,
Paul M. Markowski
,
Kelly Lombardo
,
Zachary J. Lebo
, and
Pavlos Kollias

Abstract

An engaged scholarship project called “Snowflake Selfies” was developed and implemented in an upper-level undergraduate course at The Pennsylvania State University (Penn State). During the project, students conducted research on snow using low-cost, low-tech instrumentation that may be readily implemented broadly and scaled as needed, particularly at institutions with limited resources. During intensive observing periods (IOPs), students measured snowfall accumulations, snow-to-liquid ratios, and took microscopic photographs of snow using their smartphones. These observations were placed in meteorological context using radar observations and thermodynamic soundings, helping to reinforce concepts from atmospheric thermodynamics, cloud physics, radar, and mesoscale meteorology courses. Students also prepared a term paper and presentation using their datasets/photographs to hone communication skills. Examples from IOPs are presented. The Snowflake Selfies project was well received by undergraduate students as part of the writing-intensive course at Penn State. Responses to survey questions highlight the project’s effectiveness at engaging students and increasing their enthusiasm for the semester-long project. The natural link to social media broadened engagement to the community level. Given the successes at Penn State, we encourage Snowflake Selfies or similar projects to be adapted or implemented at other institutions.

Free access
Timothy W. Juliano
,
Zachary J. Lebo
,
Gregory Thompson
, and
David A. Rahn

Abstract

The ability of global climate models to simulate accurately marine stratiform clouds continues to challenge the atmospheric science community. These cloud types, which account for a large uncertainty in Earth’s radiation budget, are generally difficult to characterize due to their shallowness and spatial inhomogeneity. Previous work investigating marine boundary layer (MBL) clouds off the California coast has focused on clouds that form under the typical northerly flow regime during the boreal warm season. From about June through September, however, these northerly winds may reverse and become southerly as part of a coastally trapped disturbance (CTD). As the flow surges northward, it is accompanied by a broad cloud deck. Because these events are difficult to forecast, in situ observations of CTDs are few and far between, and little is known about their cloud physical properties. A climatological perspective of 23 CTD events—spanning the years from 2004 to 2016—is presented using several data products, including model reanalyses, buoys, and satellites. For the first time, satellite retrievals suggest that CTD cloud decks may play a unique role in the radiation budget due to a combination of aerosol sources that enhance cloud droplet number concentration and reduce cloud droplet effective radius. This particular type of cloud regime should therefore be treated differently than that which is more commonly found in the summertime months over the northeast Pacific Ocean. The potential influence of a coherent wind stress cycle on sea surface temperatures and sea salt aerosol is also explored.

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Zachary J. Lebo
,
Ben J. Shipway
,
Jiwen Fan
,
Istvan Geresdi
,
Adrian Hill
,
Annette Miltenberger
,
Hugh Morrison
,
Phil Rosenberg
,
Adam Varble
, and
Lulin Xue
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Andreas Muhlbauer
,
Wojciech W. Grabowski
,
Szymon P. Malinowski
,
Thomas P. Ackerman
,
George H. Bryan
,
Zachary J. Lebo
,
Jason A. Milbrandt
,
Hugh Morrison
,
Mikhail Ovchinnikov
,
Sarah Tessendorf
,
Julie M. Thériault
, and
Greg Thompson
Full access