Differential Magnetometer System in Support of Space Weather Impact
Martyn, T.P., Swan. A.P., Taylor, T.L.,
Geological Survey, The Lyell Centre, Riccarton, Edinburgh EH14 4AP,
The impact of
geomagnetically induced currents (GIC) caused by severe space weather
events on ground-based infrastructure is a well known phenomenon that,
in extreme cases, has led to significant disruption to power supplies
and technologies. To better understand the effect of large magnetic
storms in the United Kingdom, a consortium of UK space weather
research institutes have jointly secured funding under Natural
Environment Research Council-sponsored research grant NE/P017231/1.
The Space Weather Impact on Ground-based Systems (SWIGS) project
comprises four work packages directed towards improving understanding
and forecasting of GIC; from magnetospheric-ionospheric sources to the
impact on infrastructure such as power lines, pipelines and railways.
As part of WP2, looking at the solid earth response to magnetic
storms, the British Geological Survey (BGS) plans to deploy a number
of remote monitoring sites close to grounded nodes in the UK power
distribution network since the lack of readily available GIC data from
network operators presently limits the verification of GIC modellling
in the UK power grid. These sites should provide proxy measurements of
the induced currents in the adjacent high-voltage overhead lines.
The proposed monitor is based on a differential magnetic variometer
system deployed on the Southern African power grid in 2013 & 2015.
Here we describe the instruments, recorders, installation and
telemetry adopted by BGS to meet the project specification of
time-stamped, one-second samples transmitting in near real-time from a
set of six sites self-sufficient in power for up to six months. The
bandwidth of interest of the study is between 10 and 10,000 seconds
and the required resolution of signal is of the order of