“Radiation Belt Remediation” Plan Could Affect HF Propagation, Study Suggests


A diagram of a radiation belt remediation system in operation (after Mozer).

NEWINGTON, CT, Aug 15, 2006 -- A New Zealand university research group believes a US Defense Advanced Research Projects Agency (DARPA) “Radiation Belt Remediation” (RBR) plan could cause major worldwide disruptions to HF radio communication and GPS navigation. DARPA reportedly envisions the (RBR) system as a way to protect low-Earth orbiting (LEO) satellites from damage caused by severe solar storms or even from high-altitude nuclear detonations. The New Zealand-based research group suggests, however, that policymakers need to carefully consider the implications of the project. Headed by Otago Physics Department researcher Craig Rodger, the research group says RBR could significantly affect radio propagation from several days to a week or longer.

“We’ve calculated that Earth’s upper atmosphere would be dramatically affected by such a system, causing unusually intense HF blackouts around most of the world,” Rodger said in an Otego University news release. “Airplane pilots and ships would lose radio contact, and some Pacific Island nations could be isolated for as long as six to seven days, depending on the system’s design and how it was operated.” GPS would likely also be disrupted on a large scale, he added.


Physicist and researcher Craig Rodger of the University of Otego in Dunedin, New Zealand.

Flushing Particles Using VLF Signals

System tests would employ extremely high-intensity, very low frequency (VLF) radio waves to “flush” particles from radiation belts and dump them into the upper atmosphere. The disruptions would result from the deluge of dumped charged particles temporarily changing the ionosphere from a “mirror” that bounces HF radio waves around the planet to a “sponge” that soaks them up, Rodger says.

The group’s paper, “The atmospheric implications of radiation belt remediation,” appears in the August edition of the international journal Annales Geophysicae. Otago University researchers collaborated with the British Antarctic Survey, the Sodankylä Geophysical Observatory in Finland and the Finnish Meteorological Institute in its preparation.

Sleight of HAND

Unclassified US Department of Defense budget documents from earlier this year propose at least initially using the High Frequency Active Auroral Research Project (HAARP) near Gakona, Alaska, “to exploit emerging ionosphere and radio science technologies related to advanced defense applications.” HAARP is jointly operated by the US Air Force and the US Navy. The project appears to be included under a program called “Sleight of HAND” (SOH).

“The effects of High Altitude Nuclear Detonations (HAND) are catastrophic to satellites,” the budget report explains. “HAND-generated charged particles are trapped for very long periods of time, oscillating between the earth’s north and south magnetic poles. This enhanced radiation environment would immediately degrade low-earth orbiting (LEO) spacecraft capability and result in their destruction in a short period of time.”

The military budget documents refer to the SOH program as “a proof of concept demonstration” of technology and techniques to mitigate the HAND-enhanced trapped radiation, with the goal of accelerating “the rate of decay of trapped radiation from the LEO environment by a factor of 10 over the natural rate of decay.”

Phase 1 of SOH would use a high-power ground-based source of VLF radiation - at least initially using the HAARP facility - “propagating through the ionosphere to deflect the trapped radiation deep into the atmosphere.” If that proves valid and cost-effective, space-based demonstrations and tests apparently would follow.

Proposal Piques Interest of Amateur Radio Community

The New Zealand research paper caught the interest of at least one newspaper, the New Zealand Herald, and word of the plan soon was circulating within the worldwide Amateur Radio community. ARRL Propagation Report Editor Tad Cook, K7RA, investigated and filed a special propagation bulletin August 15.

“When I first heard of this on Monday morning, I thought it must be something from a fringe Web site peddling dark conspiracy theories,” Cook commented, “but the newspaper reporting the news is real, and so is the team of scientists from New Zealand, the UK and Finland.” Cook contacted Rodger to learn more.

“He proved very cooperative, accessible and helpful and told me RBR is a serious project, that ‘money is starting to appear to investigate it in more detail,’ and ‘US scientists with military connections are treating it seriously’,” Cook reports.

A section of the HAARP facility antenna system near Gakona, Alaska. [HAARP Photo]

Sheer Energy

Cook says he shared with Rodger speculation by QST Contributing Editor Ward Silver, N0AX, to the effect that “the sheer energy needed to accomplish [RBR] would tend to rule it out from the start, and I don’t know where they would erect the necessary antennas.”

Responded Rodger: “This would be true, but they are hoping to rely on some of the non-linear processes in space plasmas, stealing the energy from the radiation belts to get the wave amplitudes high enough. We know this is possible - in theory - as it happens naturally already. We don’t know how easy it will be to get it happening under our control.”

Rodger says there are two plans to erect the necessary antenna. “One is to fly VLF antenna in space. This could be a power problem,” he told Cook. “But for ground-based systems, you probably already know that most major naval powers have big VLF transmitters dotted over the globe.”

Two US Navy VLF transmitters have power output capability in the megawatt range, Rodger remarked. “While these are designed to keep the signals mostly under the ionosphere, it shows the possibility for building big powerful antenna.” No mention of HAARP appears in the group’s research paper.

Ozone Layer Impact Minimal

The research group also calculated RBR’s potential to affect the ozone layer but found that ozone depletion would be short-lived and similar to that resulting from natural processes such as large solar storms and volcanic eruptions.