How well can we forecast space weather?

Space is more turbulent than it first appears. Space weather, specifically radiation and plasma emanating from our Sun, can affect Earth’s habitability. It can also negatively impact our technological systems. It is thus a very important phenomenon to understand. Despite this, most people spend a lot more time thinking about weather here on Earth rather than off it. We spoke to Delores Knipp, a professor of aerospace engineering science at University of Colorado Boulder and an affiliate of the university’s Space Weather Technology Education and Research Center. We asked her about the strengths and weaknesses of forecasting space weather.

What are some of our weakest areas of understanding when it comes to space weather?

One troublesome area is the triggering and timing of solar eruptions. This is an active area of research in which machine learning is starting to be applied.

A second area that needs attention is determining whether the mass and magnetic field from a solar eruption will arrive at Earth or miss Earth. Observations from space-based instruments, some of which have provided stereoscopic views of solar ejecta, are much more plentiful than in the past. New instruments and spacecraft are under consideration for this problem.

A third area of interest is the magnetic field in the plasma that is violently ejected from the Sun – the plasma carries with it some of the Sun’s magnetic field. The orientation of the magnetic field can support efficient exchange of energy and momentum between the moving plasma and Earth’s magnetic field if the expelled field is anti-aligned with Earth’s field. On the other hand, if the expelled field is parallel to Earth’s field, then there is a blanketing effect, which has a calming effect on space weather at Earth. This is a high priority research area.

Other major research and forecasting challenges are closer to home and have to do with space weather’s impacts on society and engineered systems. We need to be able to forecast various factors: geomagnetically induced currents in long conductors such as national power grids; the amount of heating that happens in Earth’s space atmosphere interaction region and its effect on satellite drag; and radio propagation problems with high frequency radio communication and global navigation satellite system signals.

What are some important advances being made?

There are many areas of advancement. Machine learning is helping to identify combinations of factors related to solar eruptions. There are also proposed new satellite missions to put space weather measurement “buoys” in locations that could give us two to three days’ warning of high speed solar wind targeting Earth. Another area of advancement is benchmarking for extreme storms – we are determining the worst-case scenarios and 100-year return values.

We are beginning to use Ensemble Modeling, which is already used in terrestrial weather for hurricane forecasting. We are furthermore gaining the ability to provide probabilistic forecasts rather than just yes/no forecast, which is very important. We are making new particle measurements throughout the region where humans operate spacecraft and improving our global navigation satellite system measurements of the plasma environment near Earth. By assimilating all this data, we are able to develop new forecasting schemes.

How did you become interested in space weather and what recommendations do you have for people who want to study it?

I became interested in space weather when I was a terrestrial weather forecaster in the US Air Force. I learned that Department of Defense commanders, intelligence personnel, and aircraft pilots all had reason to be interested in space weather impacts.

For those who want to dig into this field, I would recommend learning about electricity and magnetism. These forces, more than gravity, are the controllers in space weather. Of course, if one just wants to experience space weather, a trip to the high northern or southern latitudes where aurora can be seen would be exhilarating and motivating.