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By clicking on the links you will find explanations of the data and information presented in the Geophysical Section.
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For some general terms and definitions please refer to our Glossary of Solar Terrestrial Terms. |
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Clicking on this link displays a list of stations for which
near real-time magnetograms (time series plots of magnetometer measurements of
the variation of the Earth's magnetic field) are available. Selecting a station
will display the most recent magnetogram, along with limited information about
the recorded magnetometer data used to produce these plots.
Magnetometer Measurements - Components of the Earth's Magnetic Field
A magnetogram is a time series measurement of the principal components of the Earth's magnetic field as measured on the ground. The components of the geomagnetic field are as follows: h corresponds to geomagnetic north (ie. is in the direction of the mean geomagnetic field parallel to the earth's surface); d corresponds to geomagnetic east or the component perpendicular to h and tangent to the surface; z is the vertical component normal to the surface with down usually positive. An alternate set of components, especially at high latitudes is x,y and z where x and y correspond to geographic north and east respectively and z is again the vertical component. Generally in magnetograms the "secular" or averaged long term values of the components of the geomagnetic field are subtracted from the measured values so as to pick up just the short time scale variations from the mean. The variations in magnetic field components are around 100 nT while the absolute values of the components are around 50,000 nT.
Clicking on this link displays a list of index type for which near real-time index plots are available: K-index, Pulsation Index and A-index plots. Clicking on K-index Plots displays a pull-down menu of available stations. Selecting a
station from the menu list displays the most recent K-index plot. Clicking on
Pulsation Index Plots displays a series of checkboxes which can be used to
select the type of pulsation index plot to be displayed, with the plot types
grouped into time series or recurrence plots.
Following the button menu system displays a pull-down menu list of stations for
which near real-time plots of the selected index are available. Selecting a
station will display the most recent pulsation index plot. Clicking on A-index
Plots displays a time series plot of the last 28 days of planetary A-index.
Clicking on this link displays links to the most recent
colour contour maps of K-index
data from the Australian region and pc3-index data from the Australian
region.
Cosmic rays consist mainly of protons. They can originate from galactic cosmic radiation or from the Sun. Cosmic rays are observed indirectly by a device known as a neutron monitor. When cosmic ray particles enter the Earth's atmosphere they interact with the nuclei of the air molecules to produce secondary radiation. The neutrons predominate in this secondary radiation and the cosmic ray detector actually detects the secondary neutrons.
The magnetic fields entrapped in and around coronal mass
ejections exert a shielding effect on the galactic cosmic radiation that is
detected by the neutron monitors. This causes a reduction in the count rate
from the monitor, typically from about 3 to 20%. This reduction is a reliable
indicator of a geomagnetic storm with warning times of up to 24 hours or
more.
Clicking on this link will display the latest geomagnetic
warning information. When a warning of expected increased levels of geomagnetic
activity is current the green “No Warning”
icon will change to the red “Warning” Icon.
Clicking on this link will display the latest geomagnetic
alert information. When alert levels have been reached the green “No Alert” icon
will change to the red “Alert” icon. Geomagnetic alerts are issued whenever the Australian region
estimated K-index reaches 5 or greater.
Clicking on this link will display the latest GEOSTAT alert
information. The GEOSTAT (GEOmagnetic STorm Alert Tracking) system has been
developed to monitor the progress of a geomagnetic storm from its origin on the
sun (Level5), to its impact on the Earth's magnetic field and subsequent
geomagnetic storm (Level 0). The alert sequence is from 5 down to 0 to simulate
a "countdown"style to the alert levels. When alert levels have been
reached the green “No Alert” icon will change to one of the six GEOSTAT alert level icons.
If GEOSTAT alert level 0 has not occurred within four days of GEOSTAT alert
level 5 being issued, the GEOSTAT icon changes to the “Alert Fail” icon
and a message indicating the geomagnetic storm failed to eventuate is issued.
Clicking on this link will display the latest aurora alert
information. When alert levels have been reached the green “No Alert” icon
will change to the red “Alert”
icon. Aurora alerts are issued whenever the Australian region estimated
K-index reaches 6 or greater. When an alert is current the alert information
indicates the latitudinal range in terms of high, middle, low and equatorial
regions where aurora may be visible under good observing conditions. There is
also a link to reports of aurora sightings observed during previous alert
conditions.
DailyReport
Clicking on this link displays the Daily Report which provides
a summary of geomagnetic conditions observed over the previous 24 hours of the
UT day and a forecast of conditions likely for the next 3 days. Conditions are
described in terms of the following levels (in increasing order of geomagnetic
activity): "Quiet", "Unsettled", "Active",
"Minor Storm", "Major storm" or “Severe storm”.
The observed geomagnetic activity is also described in terms of an estimated K-index
and A-index. Observed geomagnetic
activity is also described in terms of Daily pc3 Indices. The
estimated A-index (planetary and for Fredricksburg, USA) for the current UT day
and the observed A-index (planetary and for Fredricksburg, USA) for the
previous UT day are also given. The final section of this report is a three day
forecast in terms of A-index (planetary) and the geomagnetic activity levels explained above. A
“COMMENT” section is often present which provides more detail on
the current space weather environment likely to effect the geomagnetic field.
WeeklyReport
Clicking on this link displays the IPS Weekly Geophysical
Report which provides a summary of geomagnetic conditions observed over the
previous week and a forecast for the next month. The observed conditions are
given in terms of K-index
and A-index values generated
from data from the Australian region. The observed conditions are also given in
terms of a text summary which notes any significant disturbances experienced
during the week. The final section of the report is a forecast of disturbances
expected for the coming month.
Clicking on this link invokes an applet which can be used
to calculate an estimate of the extent of the southern hemisphere auroral oval.
One of the input parameters to the model is the Australian region estimated
K-index. The default value is the latest Australian region estimated K-index.
The applet also allows the user to select other K-index values.
Clicking on this link displays a list of stations for which
historical magnetograms (time series plots of magnetometer measurements of the
variation of the Earth's magnetic field) are available. Clicking on a station
will display a listing of image filenames of previous magnetograms in a new
window, with the filename containing the date information. Clicking on an image
filename will display the magnetogram for that day.
Clicking on this link displays a list of the different types
of index plots for which historical plots are available. Clicking on an index
type will display a pull-down menu list of stations for which historical index
plots of that type are available. Selecting a station will display a listing of
image filenames of previous index plots in a new window, with the filename
containing the date information. Clicking on an image filename will display the
index plot for that index type for that station for that day.
Clicking on this icon displays a list of stations for which historical magnetometer data files are available. Clicking on a station will provide a listing of the historical data files available in a new window, with the filename containing date information. A file named "README" provides information on the type of compression used. Files with the extension "new" are uncompressed and contain the most recent hour of data for that day. These "new" files are usually only kept for several days, while the compressed or "zip" files are normaly kept for 28 days.
The data files contain a one line header which contains the
station code, the latitude and longitude of the station, the geomagnetic field
components in the file, the sample frequency, the resolution in (nT/LSB), a
data type identifier, and the format statement of the following data in the
file. Each line of data has the hour, minute, second, followed by the field
component data in the order given in the header.
Clicking on Geophysical Links displays a list of organisations related to Geophysical and Space-weather research and monitoring.
The Geophysical Help Page gives a short explanation of the data and information provided under each sub-section of the Geophysical Section.
Latest News consists of recent IPS news items of particular relevance to the Geophysical community. News items include predictions and reports of significant space weather occurences and udpates or additions to the IPS website and services
Australian Region Estimated K-Index and Map
Clicking on this link gives the most recent estimated K-index value and map generated
from data from all available Australian stations. The value displayed by the
icon gives the most recent estimated K-index averaged for the Australian
region. The full range of K-index icons can be viewed here. The regional contour
map is produced by contouring the estimated K-indices generated from the
available station data at the universal time indicated. The "No Data" icon
indicates that data for the previous hour was unavailable.
Australian Region pc3 Index and Map
Clicking on this link gives the most recent maximum pc3 pulsation index generated from the most recent magnetometer data from all available stations. The full range of Pc3-index icons can be viewed here. The regional contour map is produced by contouring the pulsation indices generated from the available station data for the universal time indicated. The "No Data" icon indicates that data for the previous hour was unavailable.
For more information on geomagnetic pulsations and their
effects on geomagnetic surveys please see the Educational section.
The estimated K-index for each station is derived from the
H component (or D component) of the geo-magnetic field. After subtracting the local quiet background variation for a given location, the range of the variation in H (or D) over the 3-hour interval determines K.
Whichever component, H or D, gives the largest variation in nT (nano Tesla), is
assigned a value from 0 to 9 using a predetermined semi-logarithmic scale.
Estimated K-indices generated for the Australian region are the average of the
estimated K-indices from the individual stations and have a range of values 0
to 9.
Geomagnetic pulsations are variations of the Earth's
magnetic field which are classified by their structure and frequency. Pc3
pulsations are variations in the Earths magnetic field with periods of 10 to 45
seconds (22 to 100 mHz). The Pc3 pulsation indices are generated from 20 minute
intervals of data filtered over the Pc3 pulsation bandwidth, and are calculated
from the rms value (in nanoTesla) multiplied by a scale factor of 10. Index values
are integer values 0 or greater. Indices derived from the 2 horizontal
components are referred to as "pc3" indices, while those generated
using 3 component data, where available, are referred to as "Pc3"
indices. Daily pulsation indices are derived from the individual pulsation
indices by summing the index values greater than 1 for local daytime hours.
The A-index is an arithmetic mean of the eight daily
a-index values where the a-index is the latitude adjusted amplitude equivalent
(in nanoTesla) of the estimated K-index value. Indices with the subscript
"p" usually indicate "planetary" index values, which have
been generated using a standard set of observatories from around the world.
Recurrence plots show stack plots of "daily"
pulsation indices. Each of the stack plots show index data for one solar
rotation period, 27 days, from which recurrent patterns of activity maybe
determined. Days where daily index values were unavailable are indicated by red
squares. Days where the daily index has not been fully determined (ie., the
number of individual indices required for the full day were unavailable) are
indicated by a yellow triangle. An orange star is used to indicate automated
forecast daily indices.
Warning Icons
Alert Icons
GEOSTAT Icons
K-Index Icons
Pc3-Index Icons
Other Icons
