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Description

The Hurricane and Severe Storm Sentinel (HS3) airborne field campaign used the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) instrument to collect wind and precipitation measurements. This data recipe enables users to generate a time-height plot of the measured HS3 HIWRAP radar reflectivity through a Python plotting routine. The Python routine requires users to define the GHRC OPENDAP path to a data file and measured variable of interest.  This data recipe then plots the data to provide a quick visualization of radar reflectivity.  To run this Python routine, a pre-installed version of Python and additional Python packages are required. Advanced users may alter the code to plot other HS3 HIWRAP data variables.

This figure depicts a vertical two-panel time-height plot of HS3 HIWRAP radar reflectivity.
Image Caption

This figure depicts a vertical two-panel time-height plot of HS3 HIWRAP radar reflectivity.

Supporting Software Information

TYPEACCESS
Python ScriptOpen Source

How to use

 
This data recipe is available as a Python script.  To run the Python script, please install the following Python packages: matplotlib, NumPy, and Pydap.
 

Step 1

Follow the location link on this page to access the GHRC DAAC data-recipe folder on GitHub and obtain the HS3 HIWRAP Quick View Python Script: “HS3_HIWRAP_Quickview.py”.
 
You can preview the script by clicking the file name. To download, select the green “Clone or download” button located on the right side of the webpage to download the script as a zipped file or to open on your desktop. Save the file to a desired folder location on your computer.  You may also directly copy the script from the GitHub preview and paste in within your Python environment.
 

Step 2

Open the Python environment installed on your computer and make sure the required Python packages outlined in the “How to Use” section are installed. 
 
Navigate to the location on your computer where the data recipe Python file is saved and open the file within your Python environment.
 

Step 3

This Python script contains editable fields that can be used to plot the variables provided within each HS3 HIWRAP data file. This data recipe focuses on the radar reflectivity (ref) parameter.
 
A GHRC OPeNDAP link is used to pull in and plot variables within these data files. To access the GHRC OPeNDAP, a free NASA Earth Data user account is needed to access this page.  If you do not have an account, you will first need to create one.
Earthdata Login screen

Once your NASA Earthdata account has been created, you can access the GHRC OPeNDAP for the HS3 HIWRAP data files categorized by year. Simply navigate to the desired year and day, then copy the name from the web page as shown below.

Screenshot of data file for HWRAP

Step 4

Within the Python script, to change the default data file to the one you want to use, simply paste your file name in the "datafile" variable in the region highlighted below. Make sure to update the OPeNDAP URL path to reflect the year and day of the data file in the OPeNDAP path.

Screenshot of code block with file extension highlighted.

Step 5

Within the “Set Parameters” portion of the code, there are two variables for defining the final plot font sizes.  To change the font size of the plot labels, you may alter the “pltlbl_size” variable in the area highlighted.

Screenshot of code block with the size highlighted

To change the font for the rest of the plot (e.g. axis font, color bar etc.) change the font size within the matplotlib parameters highlighted below.

Screenshot of code block with font size 10 highlighted

Step 6

Within the data file, the time field is defined in hours since the beginning of a given flight on a given date.  For the data file used in this data recipe, the start time is 00:00 UTC on October 17, 2014. To make this information more readable, the next portion of the code reformats the time field so that the time is shown in standard UTC time on the final plot.  You do not need to make an alterations to this section.

Screenshot of code block

Step 7

Once the time is formatted, the array of values containing the radar reflectivity in dBZ and associated time and range information is split in half to generate two separate panel plots.

Screenshot of code block

Step 8

The remaining code in this data recipe formats the plot.  
 
To change the color scale used, change the highlighted portion of the cmap variable shown below.  Access additional color scale options.
Screenshot of code line with gist_ncar  highlighted

This data recipe also provided the option to manually change the font size of the color bar labels. To do this, comment out the existing cbar.set_label and cbar2.set label parameters highlighted.

Screenshot of code block with label parameters highlighted.

Then, un-comment the two parameter lines provided as shown below.

Screenshot of code block with lines of code highlighted.

Step 9

To create the final plot, simply run the code and the generated plot shown below should appear.

This figure depicts a vertical two-panel time-height plot of HS3 HIWRAP radar reflectivity.

Please note that this Python script may be reused and altered to plot additional HIWRAP data variables.  This plot has not undergone any quality control measures, so additional alternations are needed for scientific use.

Dataset Information

Dataset NameHurricane and Severe Storm Sentinel (HS3) High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP)
PlatformGlobal Hawk UAV
InstrumentHigh Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP)
Science ParameterRadar Reflectivity
FormatNetCDF-4/CF
Data InformationCMR Search

Key Parameters

VariableDescriptionDimensionUnitsScale Factor
timeUTC time1Dhours (since start of flight)none
rangeRange from radar1Dmetersnone
refHIWRAP radar reflectivity2DdBZnone

Details

Last Updated

Published on

Data Centers

Global Hydrometeorology Resource Center DAAC (GHRC DAAC)