Descending the steps into the deeper part of the vault, the walls started to show signs of age. Dimly lit by a single incandescent bulb, the old concrete corridor led to another smaller room – a small square box of concrete, no bigger than an average studio apartment – also lit by a single incandescent light bulb. The room contained nothing but a couple of historical posters about geomagnetism, and some large stone pedestal. Sitting on top of one of the stone pedestals, however was a device of metal, magnet and wires, encased in a glass casing; a fluxgate magnetometer used by the British Geological Survey to record the local earth magnetic field orientation. The fluxgate magnetometer was among three used by the BGS in the Eskdalemuir observatory in Scotland in their constant and long term project of monitoring the earth’s magnetic field.
By the only entrance to the vault, a computer was constantly displaying the second by second update of the magnetic field data recorded by the fluxgate magnetometer. The data was then backed up on site, uploaded to the web, backed up in another server in the Hartland observatory – three hundred miles away from Eskdalemuir, and analyzed in the BGS space weather office in Edinburgh. The collected data represent activities happening at the core of the earth, the atmosphere, and the sun. A day before visiting the Eskdalemuir observatory, Christopher Turbitt of the British Geological Survey and I talked about the complexities of the earth’s magnetic field over tea.
By the only entrance to the vault, a computer was constantly displaying the second by second update of the magnetic field data recorded by the fluxgate magnetometer. The data was then backed up on site, uploaded to the web, backed up in another server in the Hartland observatory – three hundred miles away from Eskdalemuir, and analyzed in the BGS space weather office in Edinburgh. The collected data represent activities happening at the core of the earth, the atmosphere, and the sun. A day before visiting the Eskdalemuir observatory, Christopher Turbitt of the British Geological Survey and I talked about the complexities of the earth’s magnetic field over tea.
Fluxgate magnetometer housed within the Eskdalemuir observatory (top). Buried under the earth, temperature controlled, and magnetic free, the Eskdalemuir vault holds one of the fluxgate magnetometer systems used by the BGS to continuously record the earth's magnetic field. Here, Christopher Turbitt of the British Geological services gave me a tour of the vault (left). |
The earth’s core, I was told, gave rise to the earth’s magnetic field due to its outer, iron rich, molten metal core. As the sea of molten metal flow under the earth’s crust, the massive energy it contained produced electrical currents that spread alongside the metallic sea’s movement. It is these electrical currents that in turn produce the earth’s magnetic field, and the flowing nature of the molten metal caused fluctuations in the earth’s local magnetic fields. Moreover, Chris continued, the electrical current produced in the earth’s atmosphere along with the constant stream of charged particles produced from the sun also contribute to the distribution and strength of the earth’s magnetic field – especially the solar activity.
Leading me to one of the posters hung on the walls of the BGS office, Chris pointed out the effect of the solar activity on the earth’s magnetic field – an image of the sun, earth, and lines representing their magnetic field interactions. The sun, as Chris explained it, constantly produces streams of charged particle through its own activity. This streams of charged particle – known as solar wind – travels as plasma towards the earth and contributes in sculpting the earth’s magnetic field. Another perspective would be that the earth’s magnetic field shields the earth’s surface from constant electromagnetic bombardment from the sun. Problems arise when the sun undergo unusual high activity. This unusually high activity of the sun can give rise to an extraordinarily massive plasma discharge – solar storm.
Leading me to one of the posters hung on the walls of the BGS office, Chris pointed out the effect of the solar activity on the earth’s magnetic field – an image of the sun, earth, and lines representing their magnetic field interactions. The sun, as Chris explained it, constantly produces streams of charged particle through its own activity. This streams of charged particle – known as solar wind – travels as plasma towards the earth and contributes in sculpting the earth’s magnetic field. Another perspective would be that the earth’s magnetic field shields the earth’s surface from constant electromagnetic bombardment from the sun. Problems arise when the sun undergo unusual high activity. This unusually high activity of the sun can give rise to an extraordinarily massive plasma discharge – solar storm.
I flipped through the pages of recorded magnetic field data collected over the years by BGS’ space weather team during my second visit to the Edinburgh office. The folders – each of which bursting with sheets of paper to the brim – contain around several months of data each, arranged with care in a bookcase in the office. After several pages, Sarah Reay of the data management team came and brought me several sheets of data from the archive; a record of the strongest solar storm of the decade, along with those of the silent periods. Later dubbed the Halloween storm of 2003, the readings for the magnetic field went off-charts, and showed no signs of pattern displayed by the silent periods. Even visually, the data portrays the extent of disruptions caused by the unusually massive plasma discharge.
Data obtained from the Hartland observatory magnetometers were continuously uploaded to the web through series of fibre optics cables. Hartland also serves as a backup server for magnetometer data from the Eskdalemuir observatory (top).
A whiteboard in the British Geological Survey's space weather office in Edinburgh shows schedules of known disturbances for the staff in charge of data correction to refer to whenever a disturbance in the data need to be addressed (right). |
Along with the data for the solar storm and the silent periods, Sarah also brought with her a printout of a more recent activity detected by the sensor in the Hartland observatory. The data showed activity produced by my presence near the fluxgate magnetometer. During one of my conversation with Chris, he explained that In order for the magnetometer to probe into the activity produced by the earth’s core alongside the earth’s atmosphere and the sun, the magnetometer has to be extremely sensitive. For this same reason, the observatories are located in areas furthest away from electromagnetic interference produced by modern electrical equipment, as the smallest disturbance can cause a deviation in the reading.
In order to account for the non-natural disturbances, all BGS geomagnetic observatories employ three different fluxgate magnetometer systems, separated by 100 meters from each other. In the Eskdalemuir observatory, for example, alongside the vault, 100 meters away lies two temperature controlled, magnetic free fiberglass housing the other two fluxgate magnetometers. The redundancy in the data allows for direct comparison between each system, in case one of disturbances in one of the magnetometers. The sensitivity, along with the redundancy in the data also means that each deviation has to be accounted for, and corrected manually by the space weather staff each day.
In order to account for the non-natural disturbances, all BGS geomagnetic observatories employ three different fluxgate magnetometer systems, separated by 100 meters from each other. In the Eskdalemuir observatory, for example, alongside the vault, 100 meters away lies two temperature controlled, magnetic free fiberglass housing the other two fluxgate magnetometers. The redundancy in the data allows for direct comparison between each system, in case one of disturbances in one of the magnetometers. The sensitivity, along with the redundancy in the data also means that each deviation has to be accounted for, and corrected manually by the space weather staff each day.
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Sitting in the meeting room in the Eskdalemuir observatory, I could not help but to notice the stacks of cups placed in one end of the table. Hanged on the walls in some of the rooms are photos of previous guardians of the observatory, numbering from 10 people upwards at one time. On the desk, a guestbook dating back to 1982, partially dusty and with its pages yellowed. The observatory had not seen much visitor in the recent years. Its office was supposed to hold many scientists, now hold two; one from the BGS office, one from the Meteorogical office.
Due to the process of digitization, much of the task in the observatories became simpler. An older magnetometer from the 1920’s utilizes light sensitive paper traced by a beam of light reflected through a small mirror hanged from a magnet within coils of copper wire. The light sensitive paper has to be developed on site, and at one point, the data has to be converted into magnetic tape. The current process produces digital data, with automatic recording and data upload and transfer. |
Lying at the basement of the Edinburgh office is the British Geological Survey’s paper and magnetic tape archive. Rows and rows of filing cabinets filled with sheets of data occupied much of the space in the dimly lit room. Much of the paper archive will be digitized and removed, owing to the plan for the office to relocate to another building with less storage space. On the back of the basement were multiple shelves full of magnetic tapes. Much of these physical archives were gathered and maintained from the time of conception of the BGS itself, with the Geomagnetic department going as far back as 160 years.
Over the last 160 years (with occasional data going back to the 1600s) the Geomagnetic department of the British Geological survey has been monitoring the earth’s magnetic field in order to better understand the iron rich molten core lying underneath the earth’s mantle. The Space weather team of the geomagnetic department analyzes the daily geomagnetic data to ensure its accuracy and, along with the sunspot data from other sources, predict the possibility and onset of a severe solar storm that could potentially interfere with the electric lines on the surface. Combined with the data from observatories around the world from British Geological Survey’s Collaborators, along with satellite data from a recently launched project, BGS sought to understand the earth’s magnetosphere and its interaction with the sun’s activities. As they have done over generations prior, the British Geological Survey will continue their mission hereafter.
To learn more about the background and activities behind BGS, head to the Learn More page. For references used in this story, click here.
Over the last 160 years (with occasional data going back to the 1600s) the Geomagnetic department of the British Geological survey has been monitoring the earth’s magnetic field in order to better understand the iron rich molten core lying underneath the earth’s mantle. The Space weather team of the geomagnetic department analyzes the daily geomagnetic data to ensure its accuracy and, along with the sunspot data from other sources, predict the possibility and onset of a severe solar storm that could potentially interfere with the electric lines on the surface. Combined with the data from observatories around the world from British Geological Survey’s Collaborators, along with satellite data from a recently launched project, BGS sought to understand the earth’s magnetosphere and its interaction with the sun’s activities. As they have done over generations prior, the British Geological Survey will continue their mission hereafter.
To learn more about the background and activities behind BGS, head to the Learn More page. For references used in this story, click here.