1. Cloud Evolution and the Sea Breeze Front
Jennifer Bewley
Dept. of Marine and Environmental Systems
Florida Institute of Technology
Melbourne, FL 32901

2. Overview What is a sea breeze? What is a sea breeze front?
Satellite Cloud Edge
Radar Thin Line
Why study sea breezes?
Objectives
Method
Data
Synoptic Setting
Results
Conclusions
Questions

3. Background Information
What is a sea breeze (SB)?
Differential heating between land and sea
Formation of a thermal low over the land and a thermal high over the water
A pressure gradient forms, air flows from high to low pressure
Creates the sea breeze
Opposite effect happens at night creating the land breeze
What is a sea breeze front (SBF)?
The leading edge of the sea breeze
A drop in temperature, a wind shift, and an increase in relative humidity occurs behind the front

4. Sea Breeze Circulation
Source: <

5. Background Info. Continued…
Satellite Cloud Edge
Seen on visible or infrared satellite images
A line of cumulus clouds, parallel to the shore, with no more clouds on the seaward side of the line of development

6. Background Info. Continued…
Radar Thin Line
A region of enhanced radar reflectivity in the optically clear boundary layer detected by a sensitive Doppler radar
Intense mixing of land and marine air provides several interfaces capable of reflecting radio energy

7. Why Study Sea Breezes? Forecasting Convection, Clouds, Turbulence
Changes temperature, wind speed and direction, and relative humidity
Convection, Clouds, Turbulence
Climate Modeling
Formation of clouds
Renewable Energy
Wind and solar energy
Operationally, how can you accurately locate the SBF?

8. Objectives
To compare the location of the satellite cloud edge to the surface sea breeze front and the location of the radar thin line
To analyze the differences in the location of the indicated features and create a possible vertical profile of the sea breeze front

9. Method Team Beach Team FIT Melbourne Beach
Measured air temperature, RH, and wind speed every 15 mins.
Sky observations, water temperature, wave height and period, salinity, and dissolved oxygen were taken every 30 mins.
Team FIT
Collected data

10. Method Continued… Team Mobile Unit
Traveled west on 192, attempting to transect the SBF
The mobile unit was equipped with a wind vane, cup anemometer, and radiometer.
Wind speeds, RH, air temperature, sky observations, percent cloud cover and wind direction were recorded.

11. Method Continued…

12. Data Team Beach & Team Mobile Unit Team FIT Wind speed and direction
GOES 4 km visible satellite imagery
Melbourne NWS Doppler radar base reflectivity images
Other surface observations

13. Synoptic Setting

14. Synoptic Setting

15. Synoptic Setting

16. Results
Analyzed the progression of the cloud edge, thin line, and the surface fronts
Developed a model to find the relation of the features for each day

20. Results Continued… Location Time Distance Date Radar Cloud Edge
May 25*
N/A
25 mins behind
surface front
6.9 km behind
May 26
75 mins behind
8.1 km behind
May 27
50 mins ahead
10 mins behind
1.5 km ahead
1.7 km behind
May 25* = Strong easterly flow

21. May 25

22. May 26

23. May 27

24. Conclusions
The thin line precedes the surface front which precedes the cloud edge
The actual distances between these features vary and depend on several factors
Operationally, the satellite cloud edge may not always be a good indication of the location of the surface SBF
One improvement would be to have higher resolution data, especially satellite and radar imagery and more sampling sites

25. Acknowledgements A special thanks to…
Mr. Splitt for advising this project and aiding with the creation of figures
Mr. Leslie for the mobile renewable energy station
Andrew Condon for the synoptic maps
All the MFP students and TA’s for helping with the data collection

26. Questions?

27. Brian Zachry