Data analysis can be done by using pre-selected downloadable data (Excel files) to manipulate and plot variables, or the Aeros software to load and visualize data. Both options are presented here. The Excel files are recommended for students with some Excel experience and are more useful for calculating statistics, but the Aeros software provides a much wider selection of variables for analysis and an easier method of plotting (after a brief learning curve). Students may want to utilize both options for data analysis.
Advanced students may also wish to use technical computing software platforms of their choice for higher levels of data analysis.
Advanced students may also wish to use technical computing software platforms of their choice for higher levels of data analysis.
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(Note that data has been post-processed to a rate of 1 Hz, but has not been quality controlled)
For RF14, time is in seconds since 1300 UTC on 8/7/15. For RF15, time is in seconds since 1400 UTC on 8/9/15. Click on files in blue below to download data. Thermodynamic and Wind Variables RF14 RF15 Aircraft and Radiative Variables RF14 RF15 Liquid Water Content and Drop Count/Size Variables RF14 RF15 Drop Size Distribution Observations (bin sizes are center point of bin in microns) USHAS Data (large files can be recombined into one file per flight) RF14- Part1, Part2 RF15- Part1, Part2 CDP Data RF14 RF15 Dropsonde Observations RF14 1555 UTC 1656 UTC 1939 UTC 2000 UTC 2020 UTC 2040 UTC 2059 UTC 2120 UTC RF15 2129 UTC 2150 UTC 2219 UTC 2239 UTC 2258 UTC |
LOAD AND VIEW PRE-MADE PLOTS OF VARIABLES
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Aeros
Download the correct version of Aeros at this site: https://www.eol.ucar.edu/software/aeros Install it on your computer and open the software. To load data, go to File-->Open NetCDF-->Choose to open from ftp.eol.ucar.edu (may be on side panel)-->CSET and then select CSET_rf14.nc or CSET_rf15.nc and click Open Once the data from your selected research flight is open, you can choose the variables you want to make graphs with. Go to Displays, pick a plot type (i.e. XY). This will open a blank plot on the Aeros workspace. You can right click on the plot and chose which variables to add to the right or left (and in the case of XY on the x- or y-axis). Once the data is added to the plot you can right click on the axes to change scale, time range, etc. You can open multiple displays on your Aeros workspace at once, so spend some time exploring here. Configurations of plots may be saved (to the set drive or locally) for easier loading during future work. Dropsonde Skew-T Plots (non quality controlled) RF14 RF15 |
Data Analysis Activities
Several suggestions for data analysis activities are included here in broad form (mainly plotting and analysis, although calculations of statistics could also be done). Students less experienced with research may need more guidance in these activities then is given here. Advanced students may be instructed to complete some or all of the suggested activities and develop an individual research project beyond what is presented here. As with most research projects the options for analysis are seemingly endless, so instructors may suggest alternative activities. (If any of these are a success and can be added to this module, please email the page developer.)
Activity A (Changes with Time): Have students plot various variables vs. time to see how they change throughout the flight. These plots can be compared to a plot of altitude vs. time on the same x-axis scale so students can visualize changes with height along the flight path and have a quick understanding of how conditions change between the sub cloud layer, cloud layer, and above cloud layer. For best results, time should be manipulated into UTC if using Excel. Suggested variables for plotting include (but are not limited to) temperature and dew point, wind speed, wind direction, vertical velocity, mixing ratio or relative humidity, potential temperature, long wave and shortwave radiation, LWC, and CN drop count and mean droplet size from several instruments.
Activity B (Changes with Altitude): Using the same suggested variables as Activity A, have students plot variables vs. altitude. To further understanding of differences between marine stratus/stratocumulus region and trade wind cumulus region, they can focus on just plotting from specific time period when plane is in those conditions. One suggestion is to focus around the start and end times of the BL sampling in RF 14.
Activity C (Dropsondes): Plot (or examine premade Skew-T plots) the dropsonde data and make comparisons between conditions in different regions. Students should be able to examine height of the well-mixed layer, if there are signs of a decoupled boundary layer, cloud base height (LCL), atmospheric stability, and more. This activity is best done after students are already familiar with radiosonde data analysis.
Activity D (Drop Size Distribution): Using the UHSAS and CDP data files, students can examine how changes in drop size distribution (DSD) vary with altitude or between regimes (or between RF14 and RF15 if coupled with Activity E). Students can also focus on specific times in the flight (especially sub-cloud and in-cloud periods) to study the difference in DSD between cloud types.
Activity E (Lagrangian): Have students chose 4-6 points along the in situ sampled region in RF 14, find the latitude and longitude of each point, and then use the NOAA Hysplit Trajectory Model to find out where the air in those regions ended up during RF 15. Students can then select data around those time periods and compare "before-and-after" conditions. Ideally, some of the chosen data points would start in the stratus regime and end up in the cumulus regime so students can focus on what changes may have occurred during the transition.