ERAU CBREESE 2 IOPs and Class Procedures

Training

CSWR DOW-7 and MM arrived at ERAU on 28 June 2018. During the first two days of the deployment, students and PIs were trained by two CSWR technicians, including Alycia Gilliland who remained with DOW-7 for the duration of the deployment. Students learned the difference between high and low-frequency pulses, various elevation angles, and about range-height indicator (RHI) scans. They also learned how to operate the DOW computers, properly take notes, and were introduced to the sample outreach displays. In total, nine students and three faculty members were trained to operate the DOW and MM.

Following training, ERAU C-BREESE 2.0 students and PIs met to discuss the forecast for the upcoming week. In addition, a review lecture on sea-breeze processes and convective ingredients was given by the PIs. Unlike ERAU CBREESE, during which DOW scanning locations were not pre-determined, we identified 1–3 locations in each focus sub-region where DOW scanning could be conducted smoothly without obstructions. Scanning locations were primarily located on causeways over intracoastal waterways and were explained to the students on the first day of the deployment using Google Maps. Finally, a forecasting links page was established for students and PIs to use during the length of the deployment: http://www.shawnmilrad.com/forecast.

IOPs

IOP locations were determined the day before and/or the morning of each IOP based on the background synoptic-scale flow. Easterly background flow typically indicates that afternoon thunderstorms will occur on the Florida Gulf Coast, while westerly flow suggests afternoon thunderstorms on the Atlantic Coast. Group forecast discussions were held each morning as well as over e-mail. Each morning of an IOP, PIs, and students would meet in an ERAU Meteorology classroom to examine observational and forecast data and agree on a deployment plan. Weather discussions were informal and collaborative, with active student participation.

Once one of the pre-determined DOW scanning locations was chosen for that day’s IOP, students were divided into two teams: DOW and MM. Student roles rotated with each IOP, ensuring that each student would get experience operating both pieces of equipment. Figure 2 shows two ERAU CBREESE 2.0 students operating and taking notes inside DOW-7 during IOP
6. For the DOW team, one student was responsible for taking deployment notes, while the other students were responsible for completing the DOW worksheet (Table 1). The worksheets were stored as a Google Doc so that students could complete it on their mobile devices; this was a change from ERAU C-BREESE, for which we used paper worksheets.

Another change from ERAU C-BREESE was our ability to launch several radiosondes during the deployment. CSWR provided three radiosondes and ERAU provided the helium for the balloons. Figure 2 shows two ERAU C-BREESE 2.0 students inflating a balloon with helium prior to launch around 1800 UTC during IOP 2 in Tampa. All three radiosonde launches (IOPs 2, 5, and 7) were conducted around 1800 UTC, which provided us with a glimpse of the pre-convective environment and facilitated post-deployment research. All students present for a particular radiosonde IOP participated in the launch prior to the MM team departing to perform transects. In addition, the DOW team was able to view the sounding data and balloon path in real-time through software owned and operated by CSWR.

Figure 2: Photographs of ERAU C-BREESE 2.0 students (left) in DOW-7 during IOP 6 and (right) preparing to launch a radiosonde with help from CSWR technician Alycia Gilliland on the shore of Tampa Bay during IOP 2.

 

Once DOW-7 was deployed at the scanning location, the MM team departed to perform transects. The MM team was led by PIs Herbster and Halperin, with 1–2 rotating students participating during each IOP. MM observation paths varied by IOP but were designed to sample multiple local boundary layer and thunderstorm environments. As an example, Fig. 3 displays the MM path and various meteorological parameters during IOP 2 in the Tampa Bay region. The MM drove across the sea- and bay-breeze boundaries multiple times, as well as through the core of a thunderstorm. Students on the MM team were also required to take observation notes, as well as complete the MM worksheet (Table 2).

Worksheets and deployment notes were stored on Google Drive and were used to assess student performance. In addition, they were extremely useful in the post-deployment research portion of the course, as students were able to match data visualizations with times/observations detailed in the worksheets and deployment logs.

Figure 3: Five-panel plot of MM data during IOP2, with the MM path illustrated in the top four panels. The MM started at the DOW-7 deployment location in Tampa, FL (large circle) and completed transects through various mesoscale boundaries over the course of 2–3 hours.
 
DOW Worksheet Sample
How frequently is the DOW scanning? 35° per second
Describe the phenomenon that you are scanning. Include approximate location (direction and distance) and time information. 1945
  • Scanning a thunderstorm located to the northeast
  • •The maximum reflectivity intensity is about 43.79 away

2009

  • Westerlies (sea breeze) moved east
  • 49.10 dBZ maximum reflectivity

2017

  • Boundaries collided
What is the maximum reflectivity intensity? 1925: 51.79 dBZ
2044: decreased to 38.26 dBZ
What are the maximum radial velocity values?

Do you see any radial velocity couplets? If so, describe intensity and location.

 

Do you see a downburst signature? If so, describe intensity and location.
1925: -7.8 m s-1

1925: No true couplets, shear aloft

  • Shear: 9.86 + 1.43 = 11.29 m s-1
  • Location: 43.79 km away
2025: Downbursts recorded with rain shaft
How do the radar scans compare to what you are seeing visually? Be descriptive. 1925: We see a wall of rain outside the DOW over the bay, matching the location of the strongest reflectivity values.

Table 1: Sample DOW team student worksheet from IOP 2 in Tampa, FL. Times are in UTC.

 

MM Worksheet Sample
What is the primary objective of the MM during today’s IOP? To measure the contrast along the line roughly perpendicular to the sea breeze front.
Describe the MM observation route during the IOP. State Road 60 east to I-75 N at 1940 to I-4 E south on I-75 2002 west on 60 2035 on the island in Clearwater beach 2115 eastbound 2120
List any interesting MM observations during the IOP. Drizzle began at 1934 Hit outflow 1937
Rain began 1944
Rain changed to drizzle 1953 Lightning north of position 1958 Rain ended 2002
Drizzle began 2007
Rain began 2008
Lightning 2019, 2023, 2025, 2030, 2032, 3035, 2037
Rain began 2048
Data stopped 2135
Drizzle 2135
How do the MM observations compare to what you are observing visually and/or on the radar? After going through the boundary, temperature decreased by about 1°C and RH increased 10%.
Did the MM team achieve its objectives for this IOP? If not, explain what you might do
differently next time.
Yes, although getting stuck in rush hour traffic was a bit of a hindrance toward the end of the IOP.


Table 2: Sample MM team student worksheet from IOP 2 in Tampa, FL. Times are in UTC.

 

Class procedures

The three PIs participated in all seven IOPs. Student participation rotated based on availability and scheduling, although each student was required to participate in at least three IOPs. Course grades were based on three components: field participation, worksheet completion, and post-deployment research projects/presentations.

Following the end of the deployment, the remaining four weeks of the course were spent on group research projects that were required to incorporate both DOW and MM data. Two of the research projects focused on our most scientifically interesting IOP (IOP 4), during which we observed strong convection over Cape Canaveral followed by the development of a mid-tropospheric meso-low. A sample radar visualization of the meso-low, which was coincidentally centered very close to the DOW scanning location, is shown using DOW 8.5° reflectivity and radial velocity in Fig. 4. The two-panel display (Fig. 4) was prepared and presented by one of the post-deployment student research groups using the Unidata Integrated Data Viewer (IDV). As such, students learned how to utilize meteorological visualization software such as IDV and McIdas, which will be useful to them in future classes and/or careers.

Figure 4: Two-panel display of DOW 8.5° (left) reflectivity (dBZ) and (right) radial velocity (kt) during the IOP 4 meso-low.