Nonlinear Techniques for Short Term Prediction of the Geomagnetic Field and its Secular Variation

Abstract

Recent studies on the chaotic behaviour of the dynamical system producing the geomagnetic field , i.e. the geodynamo. These studies are based on secular variation data from observatories annual means (Barraclough and De Santis, 1997; De Santis et al., 2002), as well as on global models produced for the last century (De Santis et al., 2004), and have shown some interesting nonlinear properties. Suitable nonlinear techniques can be applied for short term prediction of the geomagnetic field, i.e. to extrapolate the field 1-2 years into the future. Using these methods it is possible to update maps of the geomagnetic field for navigational purposes and to improve the prediction of the magnetic declination at heliports and airports. Declination values are important for the safety and security of all operations related to landing and take-off.