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Tuesday, July 28, 2009

Norway in Summer

Well, its campaign time and here I am sat in the north of Norway. Except rather than snow, ice and rain I can see sunshine and mountains of green. It makes a refreshing change.

I arrived yesterday evening into lovely sunshine and warm temperatures, somewhat removed from the cold and snow into which I normally arrive.

The drive from the airport to the radar site was very picturesque and I did not have to worry about icy roads and so could relax and enjoy it.

It was almost enough to wipe away the pains of a 6am start followed by a three leg journey incorporating a high speed dash through Oslo airport to make my final connection. I was pleasantly surprised to find my luggage on the conveyor when I arrived.

I was even more pleasantly surprised to be fed reindeer when I got to the site. Good times.

This is the first time I have been abroad since my daughter was born and I am already missing her terribly. I just hope that we take some good measurements and get some nice results from this campaign to make up for being away from home.

That said I am not terribly hopeful.

I am not here looking for aurora this time. Instead I am looking for the signature of very high energy electrons. These relativistic electrons precipitate from the magnetosphere and deposit energy in the lower D-region (or even deeper). They can have significant effects on the chemistry of that part of the atmosphere.

The radar up here is capable of detecting the tell-tale signs of these electrons and provide a means of measuring the precipitation spectrum (that is the number flux and energy of the elctrons). This is not so easy to measure in space since you want to only sample the portion of the electron population that is going into the atmosphere plus you have the difficulty of a satellite moving through the region of interest creating temporal-spatial ambiguities. From the ground we can resolve those somehwat.

One of the advantages we have over astronomers using optical telescopes is that our radars are not dependent on clear skies and we can operate happily in the daytime. However we have our own limitations; whereas chances are that astronomers can go back to the same object over and over and repeat measurements, we are working in a massively dynamic system that disallows that. No two precipitation events are identical and are highly dependent on how the magnetosphere is being driven.

The problem I have is that my timing sucks., I had hoped to catch a period of high solar wind speed, a phenomenon that enhances driving of the magnetosphere and can lead to increased relativistic electron precipitation. The image above (linking to shows the Sun in extreme UV as seen by SOHO. What I needed was the dark spot in the upper middle (a coronal hole) to be slightly further around to the right as that would mean the solar wind burst I needed would be on its way.

I may yet get lucky for Thursday and Friday...

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