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Solar Terrestrial Interactions - Science topic

The solar-terrestrial interaction is dominated by reconnection between the IMF and the Earth's magnetic field and the consequences which follow from this.
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I am looking for other indicator of solar activity completely independent from sunspot number.
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It really depends on what you're interested in, in terms of solar activity (magnetic activity, radiation, etc...). You could look at the solar EUV flux or the F10.7 10.7cm radio flux as indicators of solar activity. EUV has a relatively short time record available, but F10.7 flux has been available since the 1950s. Indirectly, there are also measures of solar activity that are derived by the Earth's magnetic field variations. You could consult some of the very interesting work done by Dr. Leif Svalgaard and associates for reference and some ideas about other solar activity indices/qualifiers. Some examples (a few are open access, in case you don't have access to some of the others):
Hope this helps.
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Space weather refers to geomagnetic storms, coronal mass ejections and other atmospheric disturbances--whether by random natural sunbursts or via man-engineered causes--which will nullify and destroy cyber and electric grid systems for upwards of 6 months.
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 Hi Robert,
I am not sure if we truly know, but projects are on going to try and assess the impact of these events. I suggest you look into some recent work by Karel (Carolus) Schrijver  (see links) who is one of the guys leading this from the science side. I know in his latest preprint he discusses some of the previous risk assessments that have taken place (http://www.lmsal.com/~schryver/Public/ms/swxopinion.pdf).
Hopefully that's of some use and a good starting point!
Richard
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I am carrying out an investigation on plasma drift during the evening time, I observed that the average PRE magnitude for a complete solar cycle during the June solstice (covering May to July) peaked an hour after all other seasons had peaked. What could be responsible?
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The PRE is related to the ionosphric dynamo which is related to neutral wind. The neutral wind have seasonal variations, so it it is normal the PRE depends also of the season
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Seasonal investigations of vertical plasma drift had always shown June solstice recording the smallest magnitude.
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I suggest you read the paper by Sharma and Muldrew, Seasonal and longitudinal variations in the occurrence frequency of magnetospheric ionization ducts, which can be found in ReserchGate. The asymmetry in the angle between the geomagnetic pole and the the sun-earth line at night affects the occurrence frequency of ducts and spread F and I suspect it would also affect plasma drifts. If possible you could verify this by observing a longitudinal affect.
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Literature uses 1112 ESH for a year on GSO with north-south faced satellite. This can be found on:
"Degradation of thermal control materials under a simulated radiative space environment" by A.K. Sharma and N. Sridhara
"Evaluation of Thermal Control Coatings Degradation in Simulated Geo-Space Environment" by J. Marco and S. Remaury
and other publications. How does this value derives in detail? My approximations  show results around 886 ESH.
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Thank you very much!
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Is it convenient to use plane wave solution in spherical coordinate system? What are the conditions to be satisfied to use this approximation? Also, please suggest some references on this regard.
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Hari,
Sure, if you're sufficiently far from the source I see npo problem to approximating the flux from that source as a plane wavefront.
(for example, if I was designing a moon-based solar array I wouldn't bother calculating the angular offset of the illumination vector across a 1m wide panel).
It all depends on the solid angle that the region of interest subtends at the source - and more details about the problem wouldn't hurt.
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Imagine a gas pipeline fitted with a sensor, which measures corrosivity level. In a magnetic storm, it has a probability to be damaged but overloaded currents. How could I protect this sensor? Should I put the duct in the paths with lower resistivity?
Thank you so much
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Sandro,
Even better, put surge protection devices on the input (Google TSPD) and prevent the surge from even reaching the op-amps.
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How the asymmetric ring current affects the Dst index.
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The main cause of the asymmetric ring current is the very nature of the ion transport around our planet. Ions drift duskward and part of the ion distribution is lost through the magnetopause - especially during intense storms, when the magnetopause is usually pushed earthward by the higher-than-usual solar wind pressure (mostly due to an ICME). Consequently not all ions complete their full drifts around the planet and the result is an asymmetric ring current with maximum intensity in the duskside magnetosphere.
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I need to know the time-varying location, in terms of selenographic latitude and longitude, of the point where the line connecting the centers of the Sun and Moon intersects with the lunar surface, to the accuracy of second and kilometer, from 2000 to 2020. Thanks!
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Making such a calculation from scratch is a bit complicated, it is better to use existing model such as the SPICE kernel from NASA: http://naif.jpl.nasa.gov/naif/toolkit.html or the web-interface of JPL's Horizons: http://ssd.jpl.nasa.gov/?horizons.
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Having in mind that the f2-layer peak height in some instances during quiet and low solar activity conditions can be less than 300 km.
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When the hF > 300 there is no need to make chemical correction.
The reason why h'F and hmF2 are more often often used for obtaining vertical drift is simply because they are standard parameters more easily accessible in the ionosonde data bank. It is more appropriate to use an intermediate height, preferably the true height. Any virtual height should also be okay since the time rate of change may not be very different between the true and virtual heights. I am sending you some reprints in your e-mail address.
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Can the energy from solar cycle on magnetosphere and ionosphere be ignored on climate models?
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Up-to-date I can say that all statements in favour of solar forcing on climate are based on the pure statistical analysis, which, in practically all cases suffers from severe metodological error - the hypothesis is proposed and tested on the same data set (see for example Von Storch Analysis of climate variability). Some physical mechanisms have been proposed by Tinsley, Zherebtsov and others, but their models are qualitative, not quantittative. Hence they cannot be incorporated into any GCM. In Russia there was intensive discussion, when climate modellers declared that they are ready to include any terms into their codes. Unfortunately solar-forcing fans could not propose anything except correlations. This is an open problem.