Danish Meteorological Institute Solar-Terrestrial Physics Division

Polar Conjugate Facility

---

The Polar Conjugate Facility (PCF) is a collaboration amongst ground magnetometer data providers managing stations located at magnetically conjugate high-latitude sites. Partners in the PCF are:

• Danish Meteorological Institute (DMI, Dr. H. Gleisner) with selected stations along the Greenland west coast
• British Antarctic Survey (BAS, Dr. A. Rodger) with Automatic Geophysical Observatories
• The U.S. PENGUIn team (Dr. T. J. Rosenberg, University of Maryland) with Automatic Geophysical Observatories
• Magnetosphere-Ionosphere Science Team at SPRL, University of Michigan (Dr. C. R. Clauer and Dr. V. O. Papitashvili) with the MAGIC and Antarctic magnetometers

The scientific objectives of the collaboratory are studies of the global response of the magnetosphere-ionosphere system to variations in solar irradiance, solar wind and interplanetary magnetic field (IMF). A better quantitative understanding of the effects of solar variability on the Earth's magnetosphere and ionosphere of the Earth will contribute to providing parameters or constraints for the space weather models. The PCF aims at coordinating scientific research on specific topics which have been identified as topics of common interest to the PCF partners.

• symmetries/asymmetries in the auroral electrojet morphology
• magnetic signatures of substorm onset and development, monitored at conjugate sites (e.g., Pi2 pulsations, electrojet expansion/intensification/variation)
• time of arrival and morphology of sudden impulses (SI) at conjugate sites
• conjugate multipoint magnetic field observations in conjunction with satellite experiments. Satellites of opportunity include Ørsted (launched in February 1999) and Cluster-2 (launched in Summer 2000)

Another objective concerns the planning and mutual consultation about future upgrades and expansion of the facility. Topics for discussion include:

• increasing the data acquisition rate at all sites to at least 1 Hz
• establishing a denser Antarctic network of magnetometers, equivalent and conjugate to the DMI Greenland West Coast chain
• including further high-latitude observational capabilities in both, the northern and southern hemispheres

• potential conjugacy of traveling convection vortices (source region issues)
• the role of Pi1 pulsations as substorm onset indicator and their spatial extent

In order to facilitate joint research projects, magnetic variation measurements of selected time intervals should be freely exchanged between the PCF partners. It is suggested that a central data-retrieving facility be created at DMI where the magnetic field data from the various PCF partners are accessed remotely, merged into common format data files, and plotted on-fly showing stack-plots of both the northern and southern geomagentic disturbances.

Brief description of magnetic conjugacy