DMSP Dispersion Event Identification Software

This repository holds code and notebooks associated with the automated dispersion event search for use with data from the DMSP satellites. It supports both normal ("single") and overlapping ("double") dispersion. The main scripts are:

• download_dmsp.py - Download data from MagridalWeb. Run with --help to see options.
• download_omniweb.py - Downoad data from OMNIWeb HTTP Server. Run with --help to see options.
• run_model.py - Script to search data and plot discovered events-- you pass it a case file created with make_case_file.py.
• make_case_file.py - Generate a case file which holds all the inputs for run_model.py. Edit the variables at the top of the code and re-run the script to get it to write a file.

Literature

• da Silva, D., et al. "Statistical Analysis of Overlapping Double Ion Energy Dispersion Events in the Northern Cusp." Frontiers in Astronomy and Space Sciences 10: 1228475. https://doi.org/10.3389/fspas.2023.1228475
• da Silva, D., et al. "Automatic Identification and New Observations of Ion Energy Dispersion Events in the Cusp Ionosphere." Journal of Geophysical Research: Space Physics 127.4 (2022): e2021JA029637. https://doi.org/10.1029/2021JA029637

Requirements

• Python 3 with Miniconda/Anaconda - programming language, see environment.yml for module dependencies.

This code was developed by Daniel da Silva at NASA Goddard Spaceflight Center, who may be contacted at [email protected], [email protected], or [email protected].

Instructions

Create and activate the conda environment:

$ conda env create -f environment.yml

$ conda activate dmsp-dispersion

Now, pick a name for your run. Here, we call it myrun. It is going to be between December 1, 2015, and December 31, 2015, using the DMSP F16 satellite.

Next, use these commands to download DMSP and OMNIWeb data:

$ python download_dmsp.py 12/01/2015 12/31/2015 myrun --spacecraft_csv 16

$ python download_omniweb.py 12/01/2015 12/31/2015 myrun

Now, we will make a case file. This is an input file for the model to run.

$ python make_case_file.py myrun 16

To run the code in single dispersion mode with the threshold of 0.8, use the following command. Higher threshold means less sensitive and less false positives, but you miss more real events (See da Silva JGR2022 for discussion).

$ python run_model.py -i case_files/myrun_F16.json --threshold 0.8

To do a run in double dispersion mode, pass --double-dispersion. The thresholds ranges are a little different between single and dispersion mode: double dispersion mode prefers lower thresholds (try 0.1 to start). Double dispersion mode is also slower at about 50-60 seconds for a day of data.

$ python run_model.py -i case_files/myrun_F16.json --threshold 0.1 --double-dispersion

Check the output/ folder for plots and a CSV of detected events!