Solar magnetic carpet II: coronal interactions of small-scale magnetic fields

This paper is the second in a series of studies working towards constructing a realistic, evolving, non-potential coronal model for the solar magnetic carpet. In the present study, the interaction of two magnetic elements is considered. Our objectives are to study magnetic energy build-up, storage and dissipation as a result of emergence, cancellation, and flyby of these magnetic elements. In the future these interactions will be the basic building blocks of more complicated simulations involving hundreds of elements. Each interaction is simulated in the presence of an overlying uniform magnetic field, which lies at various orientations with respect to the evolving magnetic elements. For these three small-scale interactions, the free energy stored in the field at the end of the simulation ranges from 0.2���������2.1��1026 ergs, whilst the total energy dissipated ranges from 1.3���������6.3��1026 ergs. For all cases, a stronger overlying field results in higher energy storage and dissipation. For the cancellation and emergence simulations, motion perpendicular to the overlying field results in the highest values. For the flyby simulations, motion parallel to the overlying field gives the highest values. In all cases, the free energy built up is sufficient to explain small-scale phenomena such as X-ray bright points or nanoflares. In addition, if scaled for the correct number of magnetic elements for the volume considered, the energy continually dissipated provides a significant fraction of the quiet Sun coronal heating budget.

Regionalism as trading blocks, a comparative analysis of the legal structure of the EC and NAFTA within the context of the WTO

Geography has almost become obsolete. The world���s goods and services can now be accessed instantaneously by electronic commerce. Small and medium sized countries have felt the cold winds of change blowing, and have adopted the ���safety in numbers��� philosophy. Regional organisations throughout the world have sprung up, with their original raison d'��tre the encouragement and development of regional trading blocks. Two of the most developed regional groupings are the EU/EC and NAFTA. These two organisations represent two quite different philosophies of regional trade groupings, with contrasting legal structures. The advent of Trade Globalisation, with the founding of the WTO has brought these two approaches into confrontation, as each side of the Atlantic Ocean tries to influence the development on the naissant WTO. This paper examines the two contrasting legal structures, and the conflict on an inter regional level that they are engendering.