Advancing Solar Activity Understanding: The Mutual Role of Space Weather Activities

Advancing Solar Activity Understanding: The Mutual Role of Space Weather Activities M. Messerotti1,2 and H. Lundstedt3 1INAF-Astronomical Observatory of Trieste (Italy) 2Dept. of Physics, University of Trieste (Italy) 3Swedish Institute of Space Physics, Lund (Sweden)

Outline of the talk • The knowledge on SA relevant to SpW • The Sun as a complex system • SA as manifestation of coupled multi-scale chaotic processes • The characterization of SA • Advanced analysis and prediction of SA • Conclusions

M. Messerotti, 2005 Solar Drivers

M. Messerotti, 2005 Characteristic Time Scales of Solar Drivers M. Messerotti, 2005

M. Messerotti, 2005 Activity Triggers

Available Modelsfor Solar Drivers F. Zuccarello, 2005

The Sun as a Complex Plasma System Plasma Global Fluid Motion Global Magnetic Field Differential Fluid Motion Non-axisymmetric Motions Localized Magnetic Fields Global Fluid Motion Large Scale Magnetic Field

Solar Activity: a Manifestation ofCoupled Multi-Scale Processes LONG TIME SCALE LARGE SPATIAL SCALE FLUID MOTION MEDIUM TIME SCALE MEDIUM SPATIAL SCALE MAGNETIC TOPOLOGY SHORT TIME SCALE SMALL SPATIAL SCALE

Solar Activity: a Manifestation ofCoupled Multi-Scale Chaotic Processes LONG TIME SCALE LARGE SPATIAL SCALE FLUID MOTION MEDIUM TIME SCALE MEDIUM SPATIAL SCALE MAGNETIC TOPOLOGY SHORT TIME SCALE SMALL SPATIAL SCALE

Physical Description of Solar Activity LARGE SPATIAL SCALE MHD LARGE SPATIAL SCALE MAGNETIC ENERGY BUILD UP MAGNETIC ENERGY RELEASE SMALL SPATIAL SCALE MHD + KIN SMALL SPATIAL SCALE

Advanced Physical Description of Solar Activity LARGE SPATIAL SCALE MHD LARGE SPATIAL SCALE MAGNETIC ENERGY BUILD UP MAGNETIC ENERGY RELEASE STOCHASTICITY SMALL SPATIAL SCALE MHD + KIN SMALL SPATIAL SCALE

Observational Description of Solar Activity • Descriptor := Observable A = A ( s ; t ; E ) A |Rn with s |R3 (spatial variable) t  |R1(time variable) E |Rn(energy variable)

Characterizing an Active Region AR • Morphology Descriptor M = M ( x, y, z )  Classification • Magnetic Topology Descriptor M = M ( x, y, z )  Classification

Characterizing the Evolution of an Active Region AR • Formation Process • Time evolution of the Morphology Descriptor M = M ( x , y , z ; t ) • Time evolution of the Magnetic Topology Descriptor M = M ( x , y , z ; t)

Characterizing the Geoeffectivity of an AR AR • Formation Process • Morphology Descriptor M = M ( x , y , z ; t )  Precursor(s) • Magnetic Topology Descriptor M = M ( x , y , z ; t)  Precursor(s)

Conclusions • The complexity of SA is due to: • Stochastic character of processes • Process occurrence at different temporal and spatial scales • Time-space-energy coupling among concurrent physical processes • A global model of SA is perhaps impossibile to set up as even localized phenomena occur as outcome of the evolution of the global plasma system • One has to rely on the time series analysis of diachronic measurements of descriptors to improve the models for getting reliable forecasts

Advancing Solar Activity Understanding: The Mutual Role of Space Weather Activities