# Magnetic Plotting Service Information

## Table of contents

## Geomagnetic field plot information

Plots of the one minute variations of the geomagnetic field are available for all Canadian magnetic observatories. These plots, also referred to as magnetograms, can display the data in XYZF, HDZF, or DIF.

Following is a brief summary of the components and a description of each of the magnetogram types:

**X**component is the northward magnetic field**Y**component is the eastward magnetic field**Z**component is the vertical downward magnetic field- Intensity (
**F**) component is the scalar magnetic field - Horizontal (
**H**) component is the horizontal magnetic field - Declination (
**D**) component is the angle between true North and the horizontal component of the magnetic field - Inclination (
**I**) component is the angle measured from the horizontal plane to the magnetic field vector

### Magnetogram - XYZF

Plots of the one minute variations of the three components of the geomagnetic field are available for all Canadian magnetic observatories. These plots show the B_{x}(northward), B_{y}(eastward), and B_{z}(vertical downward) components of the magnetic field. Universal Time (UT) is used.

The mean value of the selected period for each component is removed and shown in the right margin. The vertical scaling is done in two ways. The fixed scale is determined from the maximum positive and negative variations from the mean for all components. The auto scale is determined from the variation of each component about its mean.

### Magnetogram - HDZF

Plots of the one minute variations of the geomagnetic field are available for all Canadian magnetic observatories. These plots show the horizontal (H), declination (D, the angle between true North and the horizontal component of the magnetic field), and the vertical downward (Z) components of the magnetic field. Universal Time (UT) is used.

The mean value of the selected period for each component is removed and shown in the right margin. The vertical scaling is done in two ways. For declination, the fixed scale covers the range -1° to +1° from the mean. The maximum positive or negative variation is used if the -1° to +1° range is exceeded. For all other components, the scale is computed from the maximum positive and negative variations from their mean. The auto scale is determined from the variation of each component about its mean.

### Magnetogram - DIF

Plots of the one minute variations of the intensity and direction of the geomagnetic field are available for all Canadian magnetic observatories. These plots show the declination (D, the angle between true North and the horizontal component of the magnetic field), the inclination (I, angle measured from the horizontal plane to the magnetic field vector) and the intensity of the magnetic field. Universal Time (UT) is used.

The mean value of the selected period for each component is removed and shown in the right margin. The vertical scaling is done in two ways. For declination and inclination, the fixed scale covers the range -1° to +1° from the mean. The maximum positive or negative variation is used if the -1° to +1° range is exceeded. For the intensity, the scale is computed from the variation from the mean. The auto scale is determined from the variation of each component about its mean.

## Rate of change plot information (dB/dt)

Plots of the one minute rate of change of the geomagnetic field are available for all Canadian magnetic observatories. These plots show the minute rate of change of the northward (dX/dt), eastward (dY/dt) and vertical downward (dZ/dt) components of the geomagnetic field. Universal Time (UT) is used.

The vertical scaling is done in two ways for the selected period. The fixed scale is determined from the maximum positive and negative variations for all components. The auto scale is determined from the variation of each component.

## Form Information

**Start Date**: The start year, month and day of interest.**Time**:- Start Hour : The start hour of interest.
- Duration : The number of hours of data to plot from the start date and time.

**Observatory**: Observatory opened during the date and time of interest. This list may change with the selection of time parameters. Please refer to the observatory information table on the form to see when the observatories are opened or closed.**Type of Plot**: Plot either the magnetic field or rate of change as described in the Geomagnetic field plot information section and the Rate of change plot information (dB/dt) section.**Components**: Component combinations are those commonly used in magnetic field analysis as described in the Geomagnetic field plot information section.**Scale**: For declination, the fixed scale covers the range -1° to +1° from the mean. The maximum positive or negative variation is used if the -1° to +1° range is exceeded. For all other components, the scale is computed from the maximum positive and negative variations from their mean. The auto scale is determined from the variation of each component about its mean.**Output Format**: Return the result in the following formats- PNG : Return in PNG image format.
- JPEG : Return in JPEG image format.
- CSV : Return the result in comma separated format. The first row of the file is the header containing the columns Date, Time, and the component combination requested. The rows after the header are the results.
- Accessible HTML Table : Return the result as a HTML table

## Data

The data used for plotting can be downloaded using the Digital Data Download application.