Space Weather A Research Perspective (1997) / Chapter Skim
Currently Skimming:
EARTH-SPACE "METEOROLOGY"
EARTH-SPACE "METEOROLOGY"
Pages 46-58
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 46... ...
The direct response of the upper atmosphere to a burst of solar flare ultraviolet and x-ray emissions is a temporary increase in ionization in the sunlit hemisphere of minutes to hours duration called a "sudden ionospheric disturbance." The ionization increase below 100-km altitudes is especially significant on these occasions. Solar Energetic Particle Events Particles are accelerated to "cosmic-ray-like" energies by the interplanetary shocks preceding fast coronal mass ejections and in the vicinity of solar flare sites.
|
From page 47... ...
Space Weather Storms In general, disturbances in the solar wind arrive at Earth 1-2 days after leaving the Sun. These disturbances, especially those caused by coronal mass ejections, trigger global changes in Earth's magnetic field and particle populations and are called magnetic storms.
|
From page 48... ...
Researchers believe there is a gradual transfer of solar wind energy into the magnetosphere under these circumstances because of the greater amount of interconnection between the interplanetary and Earth magnetic fields in the polar regions. Any small perturbation, like a solar wind pressure increase, or a change in the interplanetary field orientation, can release that stored energy in storm-like ways.
|
From page 49... ...
In particular, it has been found that the population of relativistic electrons trapped in the magnetosphere increases and decreases with the prevailing solar wind velocity. The stream structure of the solar wind and solar rotation produce the 27-day modulation shown below in both solar wind speed measured on the WIND spacecraft upstream of Earth and energetic electrons measured by the GOES-8 spacecraft in the radiation belts.
|
From page 50... ...
. Possibly related to these optical signatures, short-duration gamma ray bursts have been detected over thunderstorm regions on the Compton Gamma Ray Observatory, as were intense electromagnetic pulses (10,000 times stronger than lightning-related pulses)
|
From page 51... ...
file:///S|/SSB/PS_solar.gif file:///S|/SSB/PS_solar.gif [6/25/2003 4:38:02 PM]
|
From page 52... ...
file:///S|/SSB/ssispe.gif file:///S|/SSB/ssispe.gif [6/25/2003 4:38:06 PM]
|
From page 53... ...
file:///S|/SSB/cloud.gif file:///S|/SSB/cloud.gif [6/25/2003 4:38:10 PM]
|
From page 54... ...
file:///S|/SSB/MH_March_89_Auroral_Oval.gif file:///S|/SSB/MH_March_89_Auroral_Oval.gif [6/25/2003 4:38:14 PM]
|
From page 55... ...
file:///S|/SSB/ap_ssn.gif file:///S|/SSB/ap_ssn.gif [6/25/2003 4:38:22 PM]
|
From page 56... ...
file:///S|/SSB/MH_subst.gif file:///S|/SSB/MH_subst.gif [6/25/2003 4:38:25 PM]
|
From page 57... ...
file:///S|/SSB/goeswind.gif file:///S|/SSB/goeswind.gif [6/25/2003 4:38:27 PM]
|
From page 58... ...
file:///S|/SSB/spreadf.gif file:///S|/SSB/spreadf.gif [6/25/2003 4:38:32 PM]
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.