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• How To Obtain And Interpret Observatory Data (Part I)
  
• How To Obtain And Interpret Observatory Data (Part II)
  
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Tutorial

More Advanced Observations

After you become confident about interpreting the Kp index and reading magnetograms from Kiruna and Baker Lake, you can get data from other observatories. The data sources below should be used in addition to the Kp index and magnetograms from Kiruna and Baker Lake. After you have learned to use these new resources, you can go to the following observatories and collect data.

Kp Index
Kiruna, Sweden
Canada
Tromso, Norway
Alaska
Tixie Bay, Russia
Let's get started on getting and interpreting data from more observatories. We will start with Tromso, Norway. The plots that are produced by Tromso and other observatories offer slightly different information. The image below is a plot for May 30, 2003.

These plots are a little more complicated than the Kiruna plot because these scientists elected not to subtract the average Earth field from the data before plotting it. Like the Kiruna Observatory data, the Tromso Geophysical Observatory shows three curves in each plot - but these curves represent different quantities that define the magnetic field.

The Blue curve is for the horizontal intensity (H) and the Green is for the vertical intensity (Z). The vertical axis on the left shows values for the horizontal magnetic field (blue numbers) and for the vertical magnetic field (green numbers). The horizontal green and blue lines indicate the normal or undisturbed strength of the magnetic fields.

The Red curve gives the value of the angle between the north geographic and north magnetic pole (D). This seems a bit odd at first, but it is very convenient to show this angle (Red) because that's the same angle you would measure with your compass! The vertical axis on the right is the angle in degrees (red numbers)

It is easy to see just how 'stormy' things are by looking at the curve compared to its horizontal line (i.e. the green curve compared to the green line) . When there is a big difference between the current and average measurements, that means a magnetic storm is in progress in Tromso. It is also interesting to look at how complicated these magnetic storms can be with all the jumps and wiggles that happen!

When you click on Tromso at the top of the page, you will see four plots like the above from different magnetometers operated by the University of Tromso. These plots are updated every 4 minutes. If you click on home at the bottom of the page, you can get to a page that offers archived data. (Plot Archived Data)

More Observatories

Now we take a long skip across the North Atlantic to Canada to see what their observatories have to say!

When you click on the link Canada above, this will open a window you have seen before.

This set up is a rather typical window for a website that serves data to scientists. It is provided by the Canadian Geological Survey, and it is an access window to data from over a dozen magnetic observatories all across Canada. Here's how to use it.

First, enter the current month day and year into the windows by using the menu bar immediately to the right of each window, and then highlight the desired date. You will note that with this same page you could look at daily magnetic data all the way back to 2001 if you wanted to!

Now click on the 'Submit Request' button. In a few seconds you will see a window open up that looks like this:

It's a very busy page because the scientists want to show you all the data at once.

This diagram shows the data from the Canadian CANMOS observatories. For each station, the X (north) magnetic field component is shown in the left column, the Y (east) component is shown in the middle column, and the Z (vertical down) component of the magnetic field is shown in the right column. Stations are displayed starting with the most northerly at the top progressing down the page in decreasing latitude. Universal Time is used. All frames use the same scale (which automatically adjusts to cover the largest variation), so that the relative strengths of the field at different stations can be readily compared.
Just as for the scientists in Sweden, these plots have been prepared with the average field of Earth subtracted so that you can more easily see the bumps and wiggles.
What you might notice by looking down the columns of the original web page is that the plots are stacked so that vertically the same time appears for each of the three magnetic components. This means that you can quickly scan these plots from top to bottom in each component to see a magnetic storm develop, and move from one station to the next to see the storms geographic spread.
OK...now for our final hop, lets visit Alaska!
When you click on Alaska above, you will open a page that looks like this:

This shows the horizontal component 'H' magnetograms for three locations in Alaska, again with the large average field intensity subtracted so that you can see changes more easily. The greater the deflection or difference from zero, the greater the storm.
The H component is the sum of the X and Y Cartesian components of the magnetic field found by the Pythagorean Theorem H² = X² + Y².
If you want to complete our geographic grand tour of the northern magnetic observatories, you can visit a magnetic observatory in Tixie Bay, Russia. What you will find is another data portal. On the left-side, scroll down to the bottom and select the most recent date. It will create a plot in the right hand frame.
It's the same kind of plot we have seen before. Once again, a magnetic storm will appear as a large change in the readings during a span of a few hours.

How Bad Was That Storm?

Here are some examples of things to look for as you try to interpret the data in search of magnetic storms.
The following six images show different levels of magnetic activity recorded at the Kaktovik Station in Alaska during May 2003:

	1	This shows quiet conditions with no storms
	2	This shows quiet conditions with a minor storm at 16:00 to 20:00 UT
	3	This shows quiet conditions with 1 to 2 storms
	4	This shows quiet conditions ending with the onset of a disturbed period after 12:00 UT
	5	This shows disturbed conditions with 2-3 individual storms
	6	This shows a disturbed period with 3 or 4 individual storms

Use these examples as a key to assigning storm severity grades to your observation. If you see more 'excitement' than Example 6 above, assign the storm a grade of 7.

Examine the magnetometer data for the H component, (or for the X-component) reported at each observatory.

Break the data for that magnetic component into two, 12-hour segments from 0-12 and 13-24 UT.

Compare the level of activity in each of the two segments with the 6 examples above and assign them a severity index.

Example:

0	First Period	Second Period
Kiruna	4	6
Canada	5	5
Alaska	4	6
Russia	6	6
Average	4.75	5.75

Your estimate for the first period is therefore rounded to 5. During the second segment, the average was rounded to 6. Because a stormy episode is usually preceded by a calm period, (just like for ordinary thunder storms!) take the largest of the two indices as your estimate for your day's magnetic storminess.

Submit your data to S.O.N. by clicking in the left menu.
If your numerical estimates are 1 to 2, record a low storm level.
If your numerical estimates are 3 to 4, record a medium storm level.
If your numerical estimates are 4 to 5, record a high storm level.
For values over 6, record an extreme storm level.