The SGO tomography chain has been an operational instrument since early 2003, i.e. today autumn 2014, we have had one solar cycle of continuous observations. Before 2003, we did make technology and analysis development and related experiments. Early trials date back to 1990s. The basic data products are the phase curve measurements from 4-5 stations. The operational stations are: Nurmijärvi and Kokkola in Finland, Luleå and Kiruna, in Sweden. Tromsø station in Norway was used in the early phase of the chain and it was later replaced by the Kilpisjärvi receiver. The phase curves are basically total electron content plus an additive unknown constant. As analysis products, we have produced a large set of tomographic reconstructions.
As mentioned earlier in the blog, we are continuing the tomography development in collaboration with Finnish Meteorogical Institute in a project titled ‘TomoScand’. Hence, the development is active and we hope to be measuring also during next years, and hence having data for 1+ solar cycle!
|Stations measuring 2014-06-01
|Measured phase curves