Introduction
This Website is a gateway for space weather displays
based upon cosmic ray data returned by the Spaceship Earth
network of neutron monitors and from the worldwide muon detector network.
The top of the site contains reduced versions of the plots
that we consider most relevant for space weather prediction.
Click any plot to obtain an enlarged version. As our
space weather products are improved and optimized, these plots
will change from time to time.
Below is a brief description of the multi-national team providing
data for this site. Following that is a listing of available
realtime space weather displays based upon cosmic ray data, including
a link to the display and a brief discussion of its use for space weather
forecasting or specification.
Disclaimer
This is a prototype, experimental site.
Use of material on this site for any purpose
is at your own risk. We do not guarantee that the realtime displays
will be available or up-to-date at all times. Realtime data have not been
subjected to rigorous quality control; it may contain "glitches" that
produce false alarms or fail to detect true space weather disturbances.
Even when the data are good, there may be physical factors that produce
false alarms or fail to detect true space weather disturbances.
Participating Institutions
Spaceship Earth
Spaceship Earth is an 11-station network of neutron monitors strategically located
to provide precise, real-time, 3-dimensional measurements of the cosmic ray
angular distribution. Participating institutions include the
University of Delaware,
IZMIRAN (Moscow Region, Russia),
Polar Geophysical Institute (Apatity, Russia),
Institute of Solar-Terrestrial Physics (Russia),
Institute of Cosmophysical Research and Aeronomy (Russia),
Institute of Cosmophysical Research and Radio Wave Propagation (Russia),
Australian Antarctic Division (Hobart),
and the University of Tasmania (Hobart),
Chonnam National University (Jang Bogo), Chungnam National University (Jang Bogo), National Research Foundation of Korea (Jang Bogo).
For additional information on Spaceship Earth, neutron monitors,
and space weather, please visit the home page of the
University of Delaware
Bartol Research Institute neutron monitor program
Links to Space Weather Displays (with Brief Explanations)
Important Note: These plots are experimental prototypes. The display format
may change as a result of ongoing research to optimize space weather
prediction with cosmic rays.
Refer here for a brief explanation of the current display format.
DISPLAY FORMAT
Top Panel: DSCOVR magnetic field magnitude |B| (green), north-south component
Bz (dark-red) and Bx-By (blue) in GSE coordinates, and 1-hour estimated Kp index (blue).
Second Panel: DSCOVR solar wind speed (black) and density (blue).
Third Panel: 3-hour estimated Kp index.
Fourth Panel:Cosmic ray density determined by fitting a first-order anisotropy to available
Spaceship Earth stations (in the case of neutron monitor data).
or available directional channels (in the case of muon detector data).
Fifth Panel (Loss Cone Display): Each circle represents an hourly
average of the cosmic ray intensity measured by a single Spaceship Earth
station relative to the cosmic ray density (in the case of neutron monitor data)
or a single directional channel relative to the cosmic rays density (in the
case of muon detector data). Red circles indicate deficit intensity,
blue circles indicate excess intensity, and the size of the circle scales with
the magnitude of the deficit or excess; see right side of plot for scale.
Horizontal axis is time (3 days total displayed), and vertical axis is
pitch angle of the station or the directional channel.
Pitch angle is the angle between the Sunward magnetic field direction (DSCOVR
1-h average) and the viewing direction of the station or directional channel
(median rigidity particle). Here "Sunward" is defined relative to a nominal 45 degree sprial
field; a station or directional channel with zero degree pitch angle views particles coming from
the Sun along the magnetic field. Stations or directional channels were
inter-normalized by means of a 24-h trailing moving average.
Sixth Panel (Bidirectional Streaming Display):Residual deviation
after subtracting the fitted first-order anisotropy from each station or directional channel. Red and blue
now represent deficit and excess relative to a first-order anisotropy. This
plot is thus a display of higher order anisotropies in the cosmic ray pitch
angle distribution.
USE OF THIS PLOT
Loss Cone Display (fifth panel): This plot will sometimes display
a cosmic ray loss cone precursor ahead of an approaching CME shock.
The defining characteristic of a loss cone precursor
is a strong suppression of cosmic ray intensity for particles
arriving from the Sunward magnetic field direction. Thus, look for large
red circles concentrated near small pitch angles. The physical mechanism
behind loss cones is that these particles trace to the region downstream of
the shock, where cosmic ray intensity is generally suppressed (Forbush decrease).
In major storms, loss cones are often observed about 4 h in advance of shock
arrival, and may be observed 24 h in advance in rare cases. Depending
upon shock-field geometry, however, loss cones can be difficult
to detect, or absent entirely.
Bidirectional Streaming Display (sixth panel):This plot can be
used to indicate when Earth is within a large interplanetary CME.
Cosmic rays within a large CME often exhibit bidirectional streaming,
in a manner similar to the bidirectional electrons observed at much lower energy.
Intensity is suppressed near 90 degree pitch angles, and elevated near 0 and
180 degrees. Thus, look for red circles concentrated near 90 degrees,
with blue circles on both sides.
Important Note: This plot is an experimental prototype. The display format
may change at any time.
Refer here for a brief explanation of the current display format.
DISPLAY FORMAT
Top Panel: DSCOVR magnetic field magnitude |B| (green), north-south component
Bz (dark-red) and Bx-By (blue) in GSE coordinates, and 1-hour estimated Kp index (blue).
Second Panel: DSCOVR solar wind speed (black) and density (blue).
Third Panel: 3-hour estimated Kp index.
Spaceship Earth stations (in the case of neutron monitor data) or
available directional channels (in the case of muon detector data).
Fourth Panel:Cosmic ray flow direction projected into ecliptic plane, as determined
by fitting a first-order anisotropy to data from Spaceship Earth neutron monitors
or to data from the muon detector network. The GSE X-axis points
toward the Sun (upward in the plot), and the Y-axis points opposite the direction of Earth's revolution
about the Sun (leftward in the plot). Each red line segment represents an hourly measurement of the
anisotropy, with the base plotted at the time of measurement, and the head oriented according
to the direction and magnitude of the anisotropy. We follow the meteorological convention,
i.e., arrows point in the direction that the flow is coming from.
Fifth Panel:Cosmic ray flow direction projected into a plane oriented normal
to the Earth-Sun line, as determined
by fitting a first-order anisotropy to data from Spaceship Earth neutron monitors
or to data from the muon detector network. The GSE Z-axis points
northward of the ecliptic plane (upward in the plot),
and the Y-axis points opposite the direction of Earth's revolution
about the Sun (leftward in the plot). Each red line segment represents an hourly measurement of the
anisotropy, with the base plotted at the time of measurement, and the head oriented according
to the direction and magnitude of the anisotropy. We follow the meteorological convention,
i.e., arrows point in the direction that the flow is coming from.
USE OF THIS PLOT
This plot specifies current conditions in the nearby interplanetary medium.
It simply tells which way the (cosmic ray) wind blows and how strongly.
Important Note: This is a plot of nearly raw realtime data,
recommended for use only by those familiar with interpretation
of neutron monitor data. A display format more useful for nonspecialists
is under development.
DISPLAY FORMAT
Pressure corrected 1-minute data from several Spaceship Earth
stations and a few other high-latitude stations are displayed.
USE OF THIS PLOT
This plot can be used as an early warning of a large solar energetic
particle event. Look for a smooth rise at one or more stations (preferably more)
occuring over a period of 5 minutes or more, followed by a (usually) slower
decay. Generally these displays will be of interest only during cosmic
ray ground level enhancements (GLE) or major Forbush decreases.
Most of the time the displayed variations are simply statistical noise.
Isolated spikes are probably data glitches and should be ignored
if unconfirmed by other stations.
This plot displays neutron rates at individual stations. It should be
self-explanatory. Only Inuvik is
displayed above, but clicking the link will transfer to a page where eight stations
(South Pole, Thule, Inuvik, Fort Smith, Nain, Peawanuck, Jang Bogo, and Doi Inthanon) are displayed
in a similar format.
Other Cosmic Ray Displays (not realtime)
- Solar Modulation Plot.
Pressure-corrected Inuvik neutron rate (27-day means) along with monthly sunspot
number from 1960 to the present. Typically updated monthly.
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