Predictive Science - Project Zed

Background

An accurate forecast of the solar wind plasma and magnetic field properties is a crucial capability for space weather prediction. However, thus far, it has been limited to the large-scale properties of the solar wind plasma or the arrival time of a coronal mass ejection from the Sun. As yet, there are no reliable forecasts for the north-south interplanetary magnetic field (IMF) component, Bn (or, equivalently, Bz). On this web page, we use a statistics based pattern matching algorithm, along with four other models, to predict the magnetic and plasma state of the solar wind ∆t hours into the future (where ∆t can range from 12 hours to seven days ). The data and models are described only briefly below. For more information please see our 2015 paper.

Data

Our data base dates back to the early 1970's and it is updated every hour using NOAA's Space Weather Prediction Center real time solar wind page .The data includes the magnetic and plasma (speed, number density and proton temperature) properties of the solar wind. Currently, our web page displays data and results only for the three components of the vector magnetic field and the speed.

• Historic data from the early 1970's to the end of 2016 was obtained from NASA's OMNI_M dataset, using the COHOWeb data server


• Real time data is obtained from NOAA's Space Weather Prediction Center (SWPC)

This is high resolution 1-minute data which we average to 1-hour.



• Past, 1-minute high resolution data for 2017, is obtained from NOAA's DSCOVR Space Weather Data Portal

  This high resolution data is also averaged to 1-hour.

Models

Five different models can be used to forecast the properties of the solar wind (magnetic field components and speed). Below is a brief description of the models, for more details about the algorithms (in particular the pattern recognition) we refer the User to our manuscript

• Baseline Model : This is our reference model. Since on average the z-component of the magnetic field is zero the Baseline model predicts all components of the magnetic field to remain exactly zero. For other parameters, such as the speed, the Baseline model uses the average value of the parameter during the previous ∆t hours as a baseline forecast for the next ∆t hours.


• Persistence Model : This model uses the current value of the parameter to predict it's value for the next ∆t hours.


• Recurrence Model : This model takes the data from 27 days before the current date and time and uses it as the prediction for the next ∆t hours.


• Pattern Recognition : This model uses a simple pattern recognition technique for identifying previous intervals in the entire solar wind dataset that are most like the interval recently observed and use the data that follows those intervals as a set of forecasts (realizations) for what is likely to occur in the next ∆t hours.


• Turbulence Model : This model is applied only to the three components of the magnetic field. It assumes that the magnitude of each component is randomly distributed in a min/max range which we take to be -3nT/+3nT.

Coordinate System

The User can select to view the data and results using one of these three coordinate systems:

• RTN : A spacecraft centered system where R is a unit vector from the Sun to the spacecraft, T is the cross product of the solar rotational axis and R , and N completes the right-handed triad.


• GSE The Geocentric Solar Ecliptic system. X is the Earth-Sun line, and Z is aligned with the ecliptic north pole.


• GSM The Geocentric Solar Magentospheric system. X is the Earth-Sun line, and Z is the projection of dipole axis on the GSE YZ plane.

Technology

All the data and model analysis are done with R codes and displayed using R, shinyApp and plotly.

For questions about this web site please contact:

Dr. Pete Riley: pete@predsci.com

Dr. M. Ben-Nun: mbennun@predsci.com