［ 2017年03月01日 ］
RIKEN International Symposium on Data Assimilation 2017
"Data assimilation for terrestrial magnetism"
The Earth's magnetic field is primarily created by a dynamo operating in the Earth's fluid outer core, some 3000 km underneath our feet. Direct and indirect observations of the temporal variability of the geomagnetic field are based on paleomagnetic measurements, historical navigation data, magnetic observatory time series, and more recently, satellite measurements. This highly heterogeneous catalog (in terms of temporal and spatial coverage) points to a very dynamic field, which can eventually reverse polarity (with the magnetic North becoming South, and vice-versa). In this talk I will describe methodological developments undertaken over the past 10 years which aim at bringing together numerical models of the Earth's dynamo (of varying complexity) and observations of its dynamics. Two salient objectives behind these efforts are i) to better understand and constrain, in light of the available data, the physical processes at the origin of the geomagnetic variability, and ii) to be able to forecast the future evolution of the field, and in particular its potential for reversing.
|名前:Alexandre Fournier||所属:Institut de Physique du Globe de Paris|