Icicles

There are lots of icicles in this part of the world. From huge pillars of frozen waterfalls in the mountains around KAIRA, to little ones that form around the edges of your hood as you trudge through the snow. However, last week I spotted some very regular ones. At first glance they even looked fake! However, these are real and are so evenly spaced, due to the regular corrugations in the tin roof.

Icicles in Sodankylä (Photo: D. McKay-Bukowski)

Have a nice weekend, everyone!

Reindeer in the underpass

Lapland is lovely in that the place is well looked after and respected by its residents. Normally, underpasses are littered and covered in graffiti and other forms of vandalism, but not here.

I came across this underpass on the southside of Sodankylä.

Just another underpass? (Photo: D. McKay-Bukowski)

What's more, when it was built, there was a design of Lappish scenes moulded into the concrete.

Reindeer designs (Photo: D. McKay-Bukowski)

Sunshine

This might seem really dull, but for us at this time of year, the rays of sunshine are very gratifying... especially after the dark and cold. Of course, it is still bitterly cold here, but sunshine on the snow is very pretty (although it can be a bit blinding at times too).

After kaamos and lots of cloudy weather, a brief clear spell let
the sunshine glance the treetops. (Photo: D. McKay-Bukowski)

Frozen river

Today's photograph is from Sodankylä. It was taken from the bridge over the Kitinen River, looking southwards. At this time of the year, the river is frozen and it serves as a "road" for the snowmobile traffic. You can see the tracks in the snow on the frozen river surface.

Kitinen River, seen from the bridge at Sodankylä (Photo: D. McKay-Bukowski)

Notice how high the midday sun is now. It is lovely to have those few hours of sunshine. After the kaamos, one really appreciates the glimmers of sun light.

Snowy slopes

It is Friday again, so time for a photograph. Today's is of the snowy slopes of Pikku Malla, not far from the KAIRA site.

The slopes near Pikku Malla (Photo: D. McKay-Bukowski)

Reindeer herder

In Sodankylä there is a statue in honour of the reindeer herders. The Sámi people who tend the reindeer that wander freely all over Lapland. Today's photograph is of that statue.

Reindeer herder of Lapland (Photo: D. McKay-Bukowski)

KAIRA frozen

Yes, it is the Arctic, but for the most part, KAIRA copes with the cold. Having a lot of warm signal processing electronics and computers keeps the inside of the RF container pretty toasty. However, in the early hours of this morning, we came unstuck.

Due to a computer failure, we scheduled a 5 minute UPS power cycle to reset the station. In the end the outage lasted a total of 7 minutes. Following the re-establishment of power, we did not recover the cooling system. Our suspicion (although we are still working on testing and checking this is that during the outage, the load on the air-conditioning dropped, thus allowing the low outside temperatures (approx. -35 deg C) to adversely drop the pressure of the refrigerant. This caused an air-conditioning failure.

Outside temperatures. The UPS was shutdown at approx. 0400 on 20-Jan-2014.

The irony is that, when the power was re-established, the internal computing and electronics overheated. Made even worse by the near-zero humidity, giving little heat transfer capacity to cycling air. The final error message before the system self-shutdown to protect itself indicated an internal temperature of 35 deg C... some 70 deg C greater than the outside ambient!

Within an hour of this shutdown, the temperature will have plummeted again.

We have checked the site today, but there is not a lot we can do without major work. Our best chance is actually to wait for some forecast warm weather ("warm" means > -25 deg C), which is expected later this week.

In the meantime we are off air awaiting the better conditions.

Such are the hazards of Arctic operation.

Roving Researcher and the Great US Trip

Since January 5, I have been travelling in the USA. The trip started with the National Radio Science Meeting in Boulder, Colorado. After that I flew to Cleveland in order to visit the Mathematics Department of the Case Western Reserve University. We are trying to solve some high-dimensional inverse problems with around 1,000,000 unknowns. Add dynamic features to this and real-time requirement.... Well if you do it wisely, regular MacBook Pro can do the job!

Today I am giving a talk in the colloquium at the math dept for around 30 persons. Title and abstract below! I will be back in Sodankylä Jan 29 afternoon. Before the trans-Atlantic flight, I will stop in Boston for two nights and discuss our African affairs and upcoming projects!

Bayesian inversion with Gaussian stochastic difference equations

Linear stochastic difference equations provide a computationally efficient way to present certain Gaussian random processes. It is well-known that difference equations can be derived from stochastic differential equations via discretisation schemes. This makes them appealing for Bayesian statistical  inverse problems, because we can model a priori probability distributions with continuous-parameter models and make the practical computations in finite spaces. Hence we are interested for constructing stochastic difference approximations of certain Gaussian processes. We start by considering the stationary Gaussian Markov random fields and their fast approximations via systems of linear stochastic difference equations. We study discretisation schemes of the stochastic differential equations on different lattices and consider the continuous limits, i.e. the convergence of the discrete objects to the continuous objects. Then we extend the study to non-stationary random fields, i.e. anisotropic and inhomogeneous fields via numerical examples.

In the Rocky Mountains with the giant car. Note the Texas plates!!

The campus police car at the Case Western Reserve University.

CHILL weather radar

Last week I had the chance to visit the CHILL research weather radar in Greeley, CO, which is operated by University of Colorado. During my studies, I had the privilege to make some dual polarization SMPRF measurements with this radar on a weather radar course organized by V. Chandrasekar (known to most people in the field as Chandra) at my university. For this reason, the chance to finally go and see this radar in person was special to me.  

There are several things that make this radar special in the world of weather radars. It has a 9 meter dish, which might seem small for somebody coming from the incoherent scatter radar community, but it is large for a weather radar. The radar is dual polarized, with independent 1 MW peak power 2.725 GHz transmitters on both polarizations, which can operate at a 0.16% duty-cycle. The dish also hosts a low power X-band radar, which makes simultaneous S- and X-band measurements possible. 

The radome and the trailers containing the radar operating center, and the transmitters. 

Offset feed antenna, hosting the dual polarized S-band and X-band radars.  

From this perspective,  the radar dish actually seems smaller than it really is. This picture offers a better representation of the proportions. 

One of the Varian VA-87B/C klystrons, that provide the 1 MW peak power for the radar. 

The klystron cabinet.

Tree lights

Although it is dark and gloomy at this time of year, a few lights can make the landscape pretty magical. Here just a couple of lights in amongst a snow-covered tree make for a lovely point on the bleak grey landscape.

Lit trees at Lampivaara, near Luosto (Photo: D. McKay-Bukowski)

Snow tractor

Not far away (~40 km) from Sodankylä Geophysical Observatory is the Lampivaara Amethyst mine. This is the only amethyst mine in Europe. It is possible to visit the mine and pick over the rubble from the operations to try to find your own amethyst, which is lots of fun.

Also fun is the way from the visitors carpark up to the summit of the hill where the mine is located. This is a snow tractor and trailer.

Snow tractor at Lampivaara (Photo: D. McKay-Bukowski)

Can we have one for KAIRA? Please?

Glimmer of sunlight

Yesterday I caught a glimmer of sunlight. With kaamos and the overcast skies, this has been the first hint of sunshine for 2014. Admitedly it was not direct sunlight into my own eyes, but it was definitely striking the 32m EISCAT dish at Sodankylä.

A hint of sunlight on the EISCAT 32m dish at SGO. (Photo: D. McKay-Bukowski)

Wild west

This is what the wild west looks like in Lapland...

Elk skull in the snow at Lampivaara (Photo: D. McKay-Bukowski)

Well, it is actually just a photograph for Friday. Have a good weekend everyone!

Heavy snow

We've had some pretty heavy snow here in the last couple of days. It took a while to dig the car out this morning and the ploughs have been running non-stop up and down the roads around Tähtelä all morning. The trees are pretty heavily laden too and, as the wind is picking up a bit, it is advisable not to walk under them!

Snow laden tree near Lampivaara (Photo: D. McKay-Bukowski)

Combined VHF Radar and KAIRA Ionospheric Scintillation Experiment

For the next three days, KAIRA is set up to observe ionospheric scintillation of the strong radio source Cassiopeia A using mode "357".  This time, however, we are also observing with the EISCAT VHF radar, setup in a tristatic mode, with the aim of establishing what the ionosphere looks like in terms of it's density and velocity structure for the various scintillation conditions we might see.

The image shows a map of northern Fenno-Scandinavia with the locations of the KAIRA and EISCAT sites marked and a track for Cassiopeia A.  This track is of the point of the line of sight from KAIRA to the radio source where it passes through an altitude of 300km, a good estimate of the height of the ionosphere's F-region, plotted from 22:00 UT to 03:00 UT tonight.  As you can see, the track starts almost overhead at the EISCAT radar site and continues almost due northwards.  This makes it ideal for combined observations as the regions which should be causing the scintillation seen by KAIRA can be probed directly by the VHF radar, which is limited to observing overhead and to the north.

Welcome to Lapland

This week we have the Sodankylä Science Seminar. This annual event is the kick-off point for the year and we usually have participants from far and wide. coming to join in the discussions and make plans for new projects and experiments.

Typically, our visitors are flying in via Rovaniemi airport. At this time of the year, nearly all the flights are arriving in the gloom, but there is a lovely art piece on the hill behind the airport to reward them for persevering through the darkness.

The reindeer illuminations at Rovaniemi airport (Photo: D. McKay-Bukowski)

The modern office

On Wednesday we showed the first records of geomagnetic measurements made with SGO. While these are fascinating in their own right, the background equipment provoked comment, so here are some more photographs of the background scenery.

Yes, once upon a time it was really like this (Photo: D. McKay-Bukowski)

From the days when you really "dialled" a number
and the ring tone was the actual ringing of an
actual bell. (Photo: D. McKay-Bukowski)

Yes, this was what a modern office had... once upon a time!

Layer-upon-layer

We've had a bit of warm (-5 to 0 deg C) weather at SGO recently. This has led to some rather odd snow effects... typically the sort you only see in late spring. This one in particular caught my attention though. It was just outside the main institute building (Polaria) on one of the benches.

Layers of snow on a park bench (Photo: D. McKay-Bukowski)

The layering looks quite geological!

Through the archives

Yesterday we showed the records of the first geomagnetic measurements made at Sodankylä Geophysical Observatory (SGO). These were from the archive kept in the observatory library. Today, we have some more photographs from the visit to the archive.

Jyrki Manninen and Esa Turunen looking through
the archives (Photo: D. McKay-Bukowski)

Current director, Esa Turunen, with the very first
geomagnetic measurement (Photo: D. McKay-Bukowski)

Locking away the archives for another
100 years (Photo: D. McKay-Bukowski)

100 years of measuring the geomagnetic field

Today, 1st January 2014, Sodankylä Geophysical Observatory (SGO) celebrates 100 years of  official geomagnetic measurements.

Yesterday at the observatory, we went down to the archives to take a look at those very first measurements. Well, here they are:

The original measurement records from SGO.
29-Dec-1913 - 01-Jan-1914 (Photo: D. McKay-Bukowski)

Current director, Esa Turunen, inspecting the original measurement
records from the archive. (Photo: D. McKay-Bukowski)

The oldest routine task of SGO is the regular measurement of the Earth's magnetic field. These measurements began on 1st January 1914 and continue until today. The only gap in the time series is between 16th September 1944 and 1st January 1947 due to the destruction of the observatory during the Lapland War.

The magnetic measurement huts (Image: SGO)

The analogue La Cour instrument was in operation until 31st December 1995. Nowadays digital data is produced in the variation room of the observatory by a Polish torsion photoelectric magnetometer (TPM), a Russian TPM magnetometer and a Danish fluxgate magnetometer (FGE). Weekly measurements of the absolute magnetic field provide the base line control.


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