Tuesday, 26 July 2011

Greenland: Hiking to Mt Evans

The International Incoherent Scatter Radar Workshop, which was held from 18th to 23rd July in Kangerlussuaq, Greenland, had come to an end with a day of interesting and at time very amusing presentations by all seven groups of workshop participants. Since most participants, esp. those who were funded by NSF, flew out only on Monday, we had Sunday off and decided to go on a hike in order to enjoy the landscape surrounding Kangerlussuaq. Of course we just could not leave science out of the equation, and thus we chose Mt Evans as our destination, which is a hill not far from the Sondrestom Incoherent Scatter Radar. On the top of Mt Evans, there was an "aerological station" in the late 1920s and early 1930s (66° 58.25' N, 51° 0.89' W).

The first leg of the trip was by cars to the radar site. Everyone had a great time enjoying the fantastic weather in the convertibles. Photo by Phil Erickson.

A short hike from the radar site to the south-west, we came across a phased-array antenna field. This is the receiver system of the Imaging Riometer for Ionospheric Studies (IRIS). The IRIS system measures cosmic radio noise around 38 MHz in 49 narrow beams. The cosmic radio noise is attenuated during particle precipitation events increasing electron density in the upper mesosphere, i.e. the ionospheric D region. The array makes an image of this effect in 49 pixels spanning approximately a square area of 250 km by 250 km at that altitude.

Upon arrival at Mt Evans, the stunning view back towards Kangerlussuaq gives a great overview of this place. The end of the fjord is visible together with its quicksand fields, which are formed by many tons of silt coming down the river from the ice sheet every second. In the far distance one can just make out the ice sheet.

On the top of Mt Evans, there was an aerological station, which was manned and continuously operated for two years in the late 1920s. Part of the observations was to launch balloons from the structure in the photo and then track their ascend and thereby studying winds as a function of altitude. Two people were dropped here by boat with supplies for a year, and then left to do their measurements. Did they sometimes hike down to Kangerlussuaq to go to the pub? No, because Kangerlussuaq was founded only some 20 years later, in 1941. However, the reason why the US Air Force chose this location is closely related to the aerological station: this was a well-mapped and studied area.

The obligatory group photo on the summit of Mt Evans. We would've liked to stay longer and enjoy the stunning landscape, but those who had to fly out the next day with the C-130 had to "check in" their luggage already on this day by 1500 LT. So it was "back to base" after an hour or so on the top.

First photo by Phil Erickson, other photos by Thomas Ulich; click on the photos for bigger versions.

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