Usually, I tend to make an effort to make a few postings throughout the weekends, but this weekend has been a little bit of an exception. That’s because on Thursday 16th and Friday 17th November, I attended the Bureau of Meterology’s (BoM) Space Weather Users Workshop. It is held once every two years, and intended to be a customer forum where space weather product users can discuss space weather effects on their industries. This year, it was held at the Sydney Nanoscience Hub at Sydney University, with a tagline of National Security and Prosperity. Thanks to UNSW, I was afforded the privilege to attend. Here are some of the highlights and some of my thoughts.
The Sun is More Than Just the Light in the Sky
On a day-by-day basis, most people give little thought to the sun, except maybe in a weather sense. Is it sunny? Do I need to put on sun-cream? Or do I need my umbrella?
But the truth is, the sun is (practically speaking) a large nuclear explosion situated eight-light-minutes away from the Earth – one that has a bit of a cyclical temper for throwing out hot gas, charged particles and magnetic fields. These are more accurately termed solar flares and coronal mass ejections (CMEs).
How they affect Earth is less widely publicized. But the truth is, as we grow into a more interconnected, interdependent society reliant on increasing amounts of technology, we become more vulnerable to the effects of space weather. Already, it is known that space weather can affect:
- Satellites – causing malfunctions such as single-event upsets (SEU), deep dielectric discharge (DDD) and surface charging. Charged particles can linger inside the Van Allen Belts and result in accumulated damage to semiconductors over time depending on orbit. Solar panels can suffer permanently reduced output.
- Radio Signals – ionospheric disturbances from X-rays can cause HF black-outs, higher charged particles can cause sporadically enhanced communications increasing interference, scintillation multipath can swamp out signals from GNSS satellites denying availability.
- Power Systems and Telecommunications – cables can develop geomagnetically induced currents (GIC) from changes in ionospheric currents, inducing slow time-varying currents which can have significant magnitudes for long conductors oriented east-west and can destroy cables associated equipment (e.g. transformers through magnetic saturation) or cause complete grid collapse.
- Water, Gas and Railway – pipes and tracks can suffer enhanced corrosion effects causing failure.
- Aviation – loss of radio signals, but also increased exposure to radiation for passengers and equipment when traversing polar routes.
- Spacecraft and Astronauts – radiation doses could be severe and evacuation plans are probably necessary.
- Atmosphere – aurora may be visible.
That is just some of what can directly happen from regular solar storm events. Of course, not all possible effects will be felt, depending where you are on the Earth (latitude), the design of the systems involved and the alignment of any flares/CMEs and the Earth. However, what isn’t shown is the interdependency of industries on services provided by others.
Such space weather events are not that uncommon and have happened in the past – some of the most famous include:
- 1859 Carrington Event – possibly the largest solar space weather event on record.
- 1989 Hydro-Quebec Power Outage – nine hour outage of the power grid in Quebec, Canada.
- 2000 Bastille Day Event – largest event since 1989.
- 2003 Halloween Solar Storms – one hour outage of the power grid in Sweden.
- 2012 Near Miss
There have been a number of articles about the potential impacts if a solar storm were to happen today, but yet, it seems that we are still slow in taking actions to effectively deal with the possibility of another major solar storm of the scale of the Carrington Event. The truth is that it’s not that unlikely, with estimations of a chance of 12% in any decade.
Preparing for the Worst
The good news is that it seems that we are starting to take this area with a bit of seriousness. From the conference, it seems that the physics of what drives the ionospheric effects we observe, and the behaviour of the magnetic field and Van Allen belts are much better understood and modelled than I expected. However, we are still at a stage where forecasting the space weather conditions into the future is still riddled with uncertainties, and “nowcasting” the present conditions is still met with some difficulties. When it comes to the human effects of space weather, understanding and mitigating the risks, we are still at an early stage.
A number of US agencies have seemingly paved the way with a National Space Weather Strategy and Action Plan, however, the truth is that the issue is a global one and requires global co-operation to reduce duplication of efforts and ensure consistent approaches. Unfortunately, one barrier to this is the lack of open and transparent data sharing in (traditionally) siloed industries where competitive advantage is the key. One way around this, although imperfect, is to have trusted sharing such as in TISN and partner with an appropriate agency such as CIPMA to do the analysis – both organizations which I was not aware of prior to the workshop.
Addressing and mitigating issues requires a lot of scientific knowledge to understand the issues at hand – this is where academia and research comes in. To prepare for the storm, various industries have done some research to understand whether a “conventional” solar storm causes them any issues:
- AEMO has set up some procedures in case of solar storms – predominantly involves notification of downstream stakeholders and a strategy to proactively return assets to service to ensure grid stability.
- Powerlink in Queensland worked with AEMO to monitor geomagnetic induced currents in the neutrals and HV network side of their high voltage transformers on an ongoing basis. Interestingly, they saw some perturbations in neutral currents and 5th harmonic current from a 6th September 2017 X-ray flare and CME event. The magnitude was not particularly great at about 15A for a short duration, although it was probably not worst case. Interestingly, they showed the use of a fibre-optic non-conventional current transformer to monitor the high-voltage side that worked via Faraday rotation effects. This seems quite promising for non-invasive and low-risk (from HV) monitoring despite limited low-current accuracy.
- Transpower in New Zealand had ongoing neutral current monitoring for a long time, and instead moved to modelling the currents based on magnetometer readings which achieved a good agreement. They had experienced a transformer failure at Islington, which by simulation, is suspected to be caused by a neutral current flow of about 100A. Simulating for Carrington events shows neutral currents of 200 to 2000A (!!) in some of their transformers. Network based simulation showed that removing transformers from the system improved resiliency as current flow is dependent on Earth conductivity and orientation of lines – less lines increases resistance limiting flow.
- BoM have also done some modelling and work with measured data, reasoning that the difference between modelling and reality is often a scale factor due to simplified ground conductivity assumptions in their simulations. However, it did show that simply being at a higher latitude in itself did not make the grid more vulnerable to large neutral currents – although the amplitudes they simulated seemed to be “tolerable” in their scenario.
- Jemena looked at gas piping and cathodic protection. GICs make it difficult to ensure continuous protection, but unlikely to break down passivation layer due to short time-scales. May destroy insulating joints, and in coated pipes, concentration of corrosion occurs in pin-prick holes.
- It seems that widespread GPS degradation has been caused by ionospheric scintillation, however, widespread GPS loss due to radio blackout (increase in background noise) has already been seen. Prolonged loss of GPS on the ground could be major, as position, timing and navigation services all rely on the signals.
Man Made Space Weather?
One of the most fascinating presentations was given by John Kennewell of the Australian Space Academy on Space weather effects of a high altitude nuclear explosion (HANE). This, as he likes to term as “anthropologic space weather” might not be so farfetched given the present political situation.
He makes references to the Starfish Prime experiment and the resulting effects of the EMP, which are well known. What I didn’t realize was the magnitude of some of the induced pulse peaks which have some very short-rise components inducing a (claimed) 2kA on a “telephone line”. The other thing I didn’t realize was the released nucleotides can get trapped in the atmosphere at a high enough altitude to destroy low-earth-orbit satellites over time as they take a while to break-down. As a result, maybe we shouldn’t just fear space weather effects from the sun – but also locally as well.
Not So Scary … But Nifty!
Not all of the workshop was about doom-and-gloom. There was some nifty things I didn’t know about, some of which was elaborated at great detail:
- SBAS Trial on Inmarsat-4F1 – I’m aware that we had old-fashioned DGPS on MW for maritime uses, and subscription based DGPS systems for on-land uses, but the government is actually running an SBAS trial using an L-band transponder on a commercial satellite to provide three different levels of corrections. The first level is similar to WAAS/EGNOS for regular GPS users. There is Dual-frequency/Multi-constellation SBAS for better performance, although not backwards compatible. The third mode is Precise Point Positioning that requires convergence time but provides solutions better than 10cm.
- Use of GPS Radio Occultation measurements through the COSMIC/COSMIC-2 missions to help improve weather forecasting through better temperature profiling of the atmosphere by measuring the refraction of GPS signals. A technique I wasn’t aware of until now, and a little ingenius now that I think of it.
- Military presentations about the Jindalee Operational Radar Network (JORN) and improved ionospheric modelling to improve over-the-horizon radar (OTHR). Also, a presentation about their JP9101 Project Phoenix: Enhanced HF Communications System which will see faster HF communications occupying larger bandwidths become reality, and the phase-out of older technologies (such as TADIL Link-11).
- Space Weather Services from the Bureau of Meterology including Auroral Alerts which will (soon) have an auroral patrol camera in Tasmania. There is also online HF Radio prediction services (I really like GRAFEX, easy to use and quite accurate I find).
- A presentation about INSPIRE-2 cubesat of the QB-50 project (and UNSW-Eco got a mention) , which sadly isn’t going so well due to some issues with corrupted filesystems, deployment of antenna issues due to depleted batteries, damage to a comms board temperature telemetry channel and issues with the downlink. I should really get out my antenna just to capture a few frames of telemetry when I can …
I’m glad that I had the opportunity to attend the workshop, as it was quite eye-opening and interesting to be exposed to various aspects of how space weather can directly and indirectly affect our everyday lives. While it was a “Space Weather Users Workshop” targeted as a BoM customer forum, it also had many technical aspects and introductory presentations which helped reinforce concepts which I had only a brief awareness of. It has given me a lot to think about, a few tools to play with and a few numbers here and there to look at. There were also presentations of current research which made references to technology I was not aware of, and investigations showing effects of even mild storms which I was not aware of. For the most part, we live our day-to-day lives thinking that “the sun will come up tomorrow,” rather than “the sun might kill us tomorrow.”
But it’s not all doom and gloom. There’s a lot of interesting technologies that were mentioned as well, and it’s showing us that people are putting thought into it.
But … maybe the biggest message is … it’s not that hard to see an aurora – just take a holiday to Tasmania when the solar cycle picks up again in another five or six years.