OR/16/030 BGS support for INTERMAGNET: Cheongyang observatory
| Thomson, Alan W P. 2016. Geomagnetism review 2015. British Geological Survey Internal Report, OR/16/030. |
Cheongyang Observatory was established by the Korean Meteorological Administration (KMA) in 2008 and is jointly operated by the Korean Research Institute of Standards and Science (KRISS) in Daejeon. Cheongyang Observatory achieved INTERMAGNET status in December 2013. BGS staff were invited to South Korea on a knowledge exchange visit in February 2015, to follow up on a previous visit made in September 2013.
Cheongyang observatory (IAGA code CYG, N 36.4° E 126.9°, 165 m altitude) is located approximately 60km west of Daejeon in a remote mountainous area where the level of man-made electromagnetic noise is low. The purpose of the observatory is long-term monitoring of the Earth’s magnetic field, space weather monitoring, and to study the possibility of earthquake activity forecasting using geomagnetic data.
Orsi Baillie was invited by Dr Po Gyu Park, Head of Electricity and Geomagnetism, on a knowledge exchange visit to KRISS to:
- provide training in the use of BGS data processing software packages
- assist with deriving quasi-definitive and final baselines and data sets
- advise on observatory data processing and analysis practices
The exchange visit was also intended to support KRISS’s determination to continue meeting INTERMAGNET standards.
We can summarise the operational status of CYG and its data, prior to the BGS visit in February 2015, as follows:
- INTERMAGNET membership, obtained in December 2013, was based on quality controlled data from September 2012 through to August 2013
- Vector (X, Y, Z) variation data, and total field (F) data were being submitted to the Kyoto Geomagnetism Information Node (GIN) of INTERMAGNET on a next day basis (by KMA)
- Preliminary data with fixed baselines were also being submitted to the Kyoto GIN on a next day basis (by KMA).
- However, no quality control procedures were being carried out on these later data sets
- No final data had been submitted for the last 18 months, hence there was a risk of losing INTERMAGNET accreditation
When we visited in February 2015 day-to-day operations were being carried out by a PhD student, Ms Shakirah Binti Mohd Amran under the supervision of Dr Kim and Dr Park.
During the visit Ms Amran was given broad training in Geomagnetism and specific training on observatory data processing and quality control. In depth demonstration and training was also given in the use of the GDASView and IMCDView custom software packages, to aid the production of definitive magnetic observatory data. Dr Kim and Ms Amran were also interested to learn about the BGS method of baseline fitting using piece-wise polynomials.
By the end of the visit, Ms Amran was able use GDASView to:
- process absolute observations
- identify and remove erroneous variation data
- assess the quality of absolute observations using the collimation errors
- deal with discontinuities, and derive continuous baselines
Since the visit, Orsi Baillie has been in close contact with Ms Amran and as a result the observatory results for 2014 have been submitted to INTERMAGNET for review by the publication deadline.
There is a continuing dialogue between BGS and CYG to enable the production of both definitive and quasi-definitive data from the observatory. Ms Amran will complete her PhD in 2017 and plans to return to Malaysia. Therefore it is essential that the necessary observatory data processing and QC practices are in place by that time and both BGS and CYG are working towards that goal.