Hm-wave filtration in a horizontally stratified Earth's magnetosphere

Summary Drawing on papers [4, 5] a semi-quantitative model of filtration and resonance of a linearly polarized HM-wave has been constructed in a horizontally stratified Earth atmosphere. The wave is filtered in a system of 3 homogeneous layers, limited by two halfspaces. Attenuation of the wave is only assumed in the lower layer, i.e. in the ionosphere. A relation has been derived for the amplitude coupling factor H_T/H_F expressing the absolute ratio of the amplitude of the wave after transmission through the system of layers and the amplitude of the wave, incident at the system of layers. The mechanism of geomagnetic pulsations is illustrated on the principle of the resonance of a HM-wave in the Earth's magnetosphere. The magnetosphere has been replaced by the said system of layers, and the dependence of H_T/H_F=f() on the parameters of the system of layers has been studied using a computer.     

Magnetic field at the core boundary in the nearly symmetric hydromagnetic dynamo z

Summary The behaviour of the poloidal and toroidal magnetic field at the core-mantle boundary is analysed in more detail, assuming that the conductive layer in the lowest mantle is thin. We can conclude that, in the case of the Z-model of the nearly symmetric hydromagnetic dynamo, the poloidal field may be considered potential everywhere in the mantle and that the azimuthal field depends on the geostrophic azimuthal velocity in the same manner as derived in[1] and[3].

---

aau ¶rt;-amu n¶rt;nuu m n¶rt; amuu aauum n¶rt;u nu¶rt;a u mu¶rt;a n. am ¶rt;, m Z-¶rt;u nmu umuu¶rt;aum ¶rt;ua aum nu¶rt;a n umam nmua ¶rt; amuu a n¶rt;u . ¶rt;m¶rt;am na [1] u [3] auum auma aum n m auma mu.

     

Transfer impedance of a probe in a drifting plasma

au un¶rt;a umu ¶rt;a na nu nauuu ¶rt;a uam mmu amm na aa. amau aa auum m mnam u mu ¶rt;a, m unam ¶rt; ¶rt;uamuu u na.     

‘Great Powers’ in climate politics

The concept of ‘Great Powers’ extends well beyond its nineteenth century origins to current business in, for example, the EU, the UN Security Council, and the World Trade Organisation (WTO). Such core groups can be crucial to finding agreement in complex and fractured negotiations. Climate change was not initially seen as an issue for the Great Power-type architecture. The problem was of universal concern, requiring universal involvement. Moreover, climate's natural great powers (the EU, the US, China, Japan, Russia, Brazil, India, and Canada) split into three antagonistic camps: the EU pressing for sharp emissions reductions; the US, with the other developed powers, much more cautious; and China, India, and Brazil determined that action should be confined to the developed world. These divisions contributed hugely to the ineffectiveness of both the 1992 Rio convention and the 1997 Kyoto Protocol. In addition, as non-Organisation for Economic Co-operation and Development (OECD; particularly Chinese) emissions fast outgrew OECD emissions, their exclusion from any constraint became visibly untenable. So, from 2005 on, the Great Powers began to meet more closely in what became the Major Economies Forum. That cooperation contributed significantly to the 2009 Copenhagen Accord. The climate problem is of course far from being solved, but maintaining Great Power cooperation will be crucial to further progress.