Author: jruppert

As I settle into a new semester with lots of exciting new challenges and lessons, it’s fun to take a moment to dip back into summer and do a little reflecting. We had two major milestones over the summer that I’ll highlight below.

-James

1. AMS 21st Conference on Mesoscale Processes (June 23-26).
   • Katharina Schmitt gave an outstanding oral presentation on diurnal pulses that had many asking follow-up questions, after making the long trek from Germany to Boise, ID.
   • James presented on mesoscale gravity waves during a special symposium honoring Steve Koch, along with on his cloud-radiation feedback work during an INCUS/anvil cloud session.
2. Gathering in Boulder, CO for a Workshop on Understanding Cloud-Radiative Feedback at Convective Scales in the Tropics
   • James along with several student group members traveled to the NCAR Foothills Lab to team up with collaborators Rosi Rios-Berrios and Yunji Zhang for a workshop in support of our NSF project examining the role of cloud-radiation interaction in tropical cyclones. Along with our core NSF research team, this workshop brought together folks from Colorado State, CU Boulder, and NCAR to discuss progress and challenges in studying and understanding cloud-radiation interaction in tropical convection. Stay tuned: this is likely to be repeated at a slightly larger scale in the near future.

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Several members of the CSD group will be in the field this summer/early fall for the NSF-funded PICCOLO campaign (Process Investigation of Clouds and Convective Organization over the atLantic Ocean).

PICCOLO is the U.S. component of the broader U.S.-German-French ORCESTRA campaign (Organized Convection and EarthCare Studies over the Tropical Atlantic). PICCOLO involves collaborations with Florida State University (Allison Wing), Colorado State University (Michael Bell), and the University of Toronto (Morgan O’Neill).

The mission of PICCOLO is to advance our understanding of the cloud-scale processes that foster upscale development of tropical storms, which are important to the formation of tropical cyclones, among other things. A major component of this work will leverage the CSU SEAPOL dual-polarization C-band radar to sample tropical clouds. We’ll use these observations to document the organization of clouds and their interactions with incoming and outgoing radiation.

The German research vessel Meteor will carry the SEAPOL and our group on a six-week journey across the tropical Atlantic Ocean, making transects across different cloud scenes. This mission will provide the first record of such cloud observations, which are expected to significantly advance our understanding of tropical weather and climate.

Group PI James Ruppert is participating in the campaign from its start in Cape Verde to its finish in Barbados, while students Emily Luschen, Mac Syrett, and Colin Welty will join in Barbados to support weather balloon launches.

Since we’re expecting to have an extremely active Atlantic hurricane season, this mission promises to be exciting and in a host of ways!

Check out Emily’s first journal article as lead author, published in the journal Geophysical Research Letters!

Luschen, E. W., and J. H. Ruppert, Jr., 2024: Longwave radiative feedback due to stratiform and anvil clouds. Geophys. Res. Lett., 51. DOI: 10.1029/2024GL108668.

Her paper deepens our understanding of tropical storms and hurricanes by advancing our understanding of their earliest stages of formation. The paper presents a new cloud-identification algorithm and applies it to show which cloud types play the biggest role in cloud–radiative feedback.

Major congrats to Emily on her first pub!

The Convective Storm Dynamics group is recruiting to fill multiple new GRA positions to begin in Fall 2024 either at M.S. or Ph.D. levels.

One GRA position focused on studying the nature and governing mechanisms of deep convective organization in the context of the Atlantic ITCZ. This position entails spending ~one month in the tropical Atlantic during the Aug-Sept 2024 PICCOLO (Process Investigation of Clouds and Convective Organization over the atLantic Ocean) field campaign.

One GRA position focused on examining tropical convective-scale dynamics. Supported by the National Science Foundation.

Two GRA positions (tied to multiple School of Meteorology research groups) to study the interaction between the tropics/poles and midlatitudes to advance our understanding of blocking events. Supported by the Department of Energy.

Curious about the influence of midlevel shear on supercell behavior? Look no further than this paper now out in JAS early online release, led by Andrew Muehr, junior undergraduate of our group:

Muehr, A. J., J. H. Ruppert, Jr., M. D. Flournoy, J. M. Peters, 2023: The Influence of Midlevel Shear and Horizontal Rotors on Supercell Updraft Dynamics. J. Atmos. Sci., DOI: 10.1175/JAS-D-23-0082.1

Major congratulations to Andrew on his first pub!

How does Coriolis deflection work? Shouldn’t projectile motion follow a straight path? If not, then how, when, and why not? Today we grappled with these questions in James’s Atmospheric Dynamics 1 (METR 3113) class by taking advantage of the phenomenal weather on a late-summer day in Norman. The idea: one volunteer moves across the human circle following a straight path (to their perception) while the surrounding people walk out the path of the circle.

The mind-bending insight: to the rotating viewers (akin to people residing on Earth, in the rotating reference frame), the path is curved, while someone standing still in or outside the circle simply sees a straight path. 🤯 🤯

Major shoutouts to 1) Jon Aurnou and the DIYnamics crew for inspiration for this activity at the Earth Educators’ Rendezvous 2023, and 2) OU student Parker Davis for volunteering to take these photos!

Last week, Emily Luschen successfully defended her M.S. thesis, titled “The Stratiform Radiation Effect on Tropical Organized Deep Convection.” She hit it out of the park with a super clear presentation and handling Q&A with style. Congrats, Emily, and we’re excited to see where you’ll continue taking this work!

This also marks a major milestone for our group, with Emily officially being the first grad student to defend as a Ruppert advisee!

A massive moment for Emily Luschen’s career: she is now the recipient of a prestigious NSF GRFP fellowship! Her research proposal focused on understanding how cloud–radiation feedback affects and accelerates the formation of tropical cyclones, which she will also investigate in relation to climate change during her PhD research. Congrats to Emily!!

Our sophomore Andrew Muehr also received a major nod for a major career milestone: his first lead-authored manuscript, which is on the role and influence of midlevel shear on supercells. While impressive on its own for his career stage, this manuscript earned him the Mark & Kandi McCasland Award for Outstanding Undergraduate Research Paper from the SoM. Congrats to Andrew!! This paper is now out for peer-review, so stay tuned.

A double-congrats to our new addition: junior Robby Frost. Robby was just awarded the Edwin and Lottie Kessler Memorial Endowed Scholarship in Meteorology from the SoM for outstanding work as an undergraduate researcher. Robby was also awarded a NOAA Lapenta internship to spend this summer working at the Earth System Research Lab in Boulder, CO. Robby is living a double-researcher life, one on tropical cyclones with our group and another on boundary layer dynamics with Prof. Scott Salesky’s group. Congrats to Robby!!

Major congrats to our other new addition, junior Colin Welty, who just found out he received an OU Provost’s Undergraduate Research and Creative Activity (UReCA) Fellowship. This award funds Colin to spend his summer on a research topic that he proposed, which will look at the role of the diurnal cycle in the overland intensification of Tropical Storm Erin, which intensified over Oklahoma in 2007. A remarkable case to study and a fantastic award. Congrats to Colin!!

This summer was a rare opportunity in which ALL group members got to be out in the field to support the collection of observations, across a range of meteorological contexts.

James Ruppert, Theresa Lincheck, and Emily Luschen participated in the PRECIP 2022 field campaign (Prediction of Rainfall Extremes Campaign in the Pacific). Theresa traveled to a small island called Yonaguni, Japan, while James and Emily were supporting operations in Taiwan. PRECIP’s mission is to use radar and radiosonde observations to sample and better understand extreme rainfall, which comes to this region in the form of typhoons, afternoon downpours, and the southwesterly summer monsoon (the “Mei-yu”). Read more about our PRECIP involvement here and here.

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Emily West traveled to Kigoma, Tanzania and Nsumbu National Park in Zambia help collect wind and temperature measurements. These measurements are critical for characterizing lake upwelling and nutrient transport, which helps sustain the local fishing industry. This fieldwork is led by the research group of Dr. Michael Soreghan of OU’s School of Geosciences.

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Andrew Muehr traveled around the Great Plains as part of the TORUS field campaign (Targeted Observation by Radars and UAS of Supercells). Andrew served on the crew of one of the windsond vehicles (shown below). TORUS is trying to answer the question of what specific details about a supercell’s behavior promotes the development of a tornado.

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Finally, Hrag Najarian is headed to Cape Verde this August as part of the CPEX-CV field campaign (Convective Processes Experiment – Cabo Verde). This NASA campaign intends to study tropical convection and associated processes that affect the dynamics of the tropical North Atlantic.