Sine May 2012 I’m the managing partner of Mertl Research GmbH. My office is at the AdhocPad in Vienna, which is not an ordinary office space: relaxing atmosphere, a workshop in the cellar, many machines to play with, a miniramp in the backyard and, most important, a bunch of creative and open-minded people.

I’m looking forward to getting the hands on the dataset and to screen the seismic data. We’ll have the recording of the complete period of the filling of the lake and the visually well documented outburst !!
Enjoy the photos taken by Gernot and Kirstine:

An article in german can be found here: ZAMG article.

* add k_0 keyword for projection = ‘tmerc’ so UTM zones can be created. Also can be used with ‘lcc’,'omerc’ and ‘stere’. Added “utmtest.py” example.

Here you can find the utmtest.py file in the git repository of the basemap package which demonstrates how to create UTM projections.

This is very helpful for the pSysmon development for which I decided to use WGS84 lat/lon and UTM projected coordinates. pSysmon can now be run using the official basemap version without any custom patches applied. This is a great value for the installation process.

The only thing that’s a little bit disturbing is, that the projected coordinates are changed so that the left bottom corner becomes the 0/0 point. It would be cool to have an option to select whether the coordinates should be reduced or not.

I wrote two small functions to compute the UTM zone from the longitude and vice versa:

def lon2UtmZone(lon):
    '''
    Convert a longitude to the UTM zone.
 
    The formula is based on the wikipedia description:
    The UTM system divides the surface of Earth between 80S and 84N latitude
    into 60 zones, each 6 of longitude in width. Zone 1 covers longitude 180
    to 174 W; zone numbering increases eastward to zone 60 that covers
    longitude 174 to 180 East.
    '''
    if lon < -180 or lon > 180:
        raise ValueError('The longitude must be between -180 and 180.')
 
    return (int((180 + lon) / 6.0) + 1) % 60

def zone2UtmCentralMeridian(zone):
    '''
    Compute the middle meridian of a given UTM zone.
    '''
    if zone < 1 or zone > 60:
        raise ValueError('The zone must be between 1 and 60.')
 
    return zone * 6 - 180 - 3

We assembled our stand at the glacier and mounted the wind turbine and the solar panels. The equipment box is mounted free-hanging below the stand to avoid problems like tumbling during the snow-melting.

We built a stand with 4 legs and a pole. The stand was stabilized using steel cable. On the pole, the windturbine, the GPS receiver and the solar panels were mounted. All the electronic equipment and the battery were put into a Zarges Box which was attached to the bottom of the pole. The box was mounted freely suspended to a tipping over of the box when the snow-melting starts. Setting up the stand took us about 15 minutes and attaching all the equipment took another 2 hours.

After the days in the workshop we finally were set to pack our stuff onto the snow scooters and start with the deployment on the glacier……more on this in the next article.

The results of their studies revealed some very interesting englacial features (see figure 1) which are most likely related to the outburst of the glacier dammed lake Lake A.P.Olsen.

Figure 1: GPR crosssection. (source: ZAMG, Daniel Binder)

The Lake A.P. Olsen fills every year during summer and it empties sometime between autumn and spring. The Zackenberg GeoBasis research programme has installed a timelapse camera at the lake which takes an image every day. These photo sequences proof, that the lake empties very fast within one day (see figure 2).

Figure 2: The lake fills up during summer and it empties every year. The time when the lake empties is not fixed. It happens sometime between autumn and spring. (source: GeoBasis)

With this information we planned a seismic- and geodetic monitoring network to be deployed at the A.P.Olsen glacier. The network should be operating one year to catch the whole cycle of the filling and emptying of the lake. Moreover a dense GPR study is planned to further investigate the area of the glacier having the englacial features. Figure 3 shows the monitoring network which we installed at the A.P.Olsen glacier during our stay in 2011.

Figure 3: The Lake A.P.Olsen monitoring network consists of 5 seismic/gps stations (APO1 to 5) and one gps reference station (APO6) at the terminus of the glacier. (orthophoto source: GEUS)

In the next part of this series I’m going to give you some more details on the construction of the stations and how we set everything up at the Zackenberg base station.

As a teaser two screenshots of the geometry dialog follow. The geometry of the seismic networks is read from the database and XML files. The content of the inventory read from an XML file can be saved to the database. The assignment of stations and sensors is done by drag’n'drop. The geometry can be checked visually in a map and the sensor’s transfer functions will also be plotted.