Exkursion 2019

Université de Fribourg / Schilthorn

September 16th

Short summary

As our first trip within Switzerland, we visited a permafrost measuring site on the north face of Schilthorn, a mountain peak in the Bernese Alps, famous for its rotating restaurant which was featured in the first James Bond movie. After reaching the mountain top with cable cars, we met with Christian Hauck representing the Department of Geosciences of the University of Fribourg. Christian Hauck gave a comprehensive overview on cryospheric research in general, focusing on the permafrost research on site, whilst placing the research in the context of a warming climate.

The site

Schilthorn
The mountain peaks at 2970m and its location enables a majestic panoramic view on the Alps, with good visibility even Black Forest can be seen (we actually had this opportunity). Also, the famous triple peaks of Eiger, Mönch and Jungfrau can be seen from there quite nicely. The area tries to attract more people during summer as the skiing conditions in the Alps are declining with a warming climate. The area is famous for paragliding and the second last cable car station below the peak, Birg, has a free ‘thrill walk’, a 200m cliff pathway with some few exciting features as a glass floor or a crawl-through tube made of wires.
Piz Gloria and James Bond
Also located on the peak is a rotating restaurant, Piz Gloria, which turns around its vertical axis in under one hour, so that guests can have the whole panorama while eating. Revolving around its axis, the restaurant glides past more than 200 mountain peaks.
There is also an interactive exhibition that takes you to James Bond world. On the big screen visitors can see images from James Bond movie “On Her Majesty‘s Secret Service”.

The science

What is the Cryosphere?
Briefly, the cryosphere can be defined as ‘everything frozen except from clouds’ (referring to the earth system). Thus, this includes glaciers, permafrost (as part of frozen ground), ice sheets, sea ice, lake and river ice, snowpack and ice caps.
What is permafrost and why is it important?
Permafrost is ‘permanently frozen ground’, often defined as ground, e.g. soil, sediments or rocks, maintaining a temperature below 0°C for two consecutive years, which is a key difference to only seasonally frozen ground. The soil and ice in permafrost stay frozen all year long and the top layer (called active layer) is thawing in summer and freezing in autumn.
Two important physical effects of permafrost with respect to the earth system are its capability to potentially release considerable amounts of carbon to the atmosphere when thawing and its stabilizing function for alpine slopes. On the day we visited, the permafrost started about 6m below the surface.

What is happening to permafrost in the Alps?
Permafrost warming and thickening of active layer (recently almost to 10 meters) has been observed due to increased air temperatures. Also, degradation of permafrost is faster than it was expected.
What is difficult about permafrost research?
Relevant areas are usually quite remote or elevated, so that equipment for setting up a measurement station has to be carried with a helicopter, which is quite expensive. Even maintaining existing stations takes a lot of time and effort. This is why the group of Christian Hauck aims to switch from invasive methods like boreholes to geophysical non-invasive methods using electromagnetic or seismic waves to assess relevant properties of the ground.

What (geophysical) research is conducted at the University of Fribourg?
The Department of Geosciences at University of Fribourg does research in alpine geomorphology, applied mineralogy, archaeometry, cryosphere, geology-tectonics, micropaleontology, paleontology, sedimentology, global environment change, human geography and environmental justice. During this excursion we got to know about activity of the Cryosphere Research Group. Its projects center on dynamics and evolution of the mountain cryosphere with emphasis on interactions with atmospheric changes. The research Group conducts several long-term monitoring programs, such as GLAMOS and PERMOS.
GLAMOS - Glacier Monitoring in Switzerland - documents and monitors long-term glacier changes in the Swiss Alp.
PERMOS is the Swiss Permafrost Monitoring Network. It systematically documents the state and changes of mountain permafrost in the Swiss Alps. PERMOS operates two types of sites:

  • 14 temperature sites, where borehole temperatures, ground surface temperatures and near-surface temperatures, borehole temperatures, and changes in subsurface ice and unfrozen water content are measured
  • 14 kinematics sites, where permafrost creep and fast mass movements (e.g., rock fall) are observed
    Additionally, at temperature sites, meteorological data, such as air temperature, relative humidity, net radiation, snow depth, wind speed and direction, are recorded.

Schilthorn measuring site is designated as PERMOS Reference Site, which is main for the network and is treated with priority. It has a meteorological station, instrumented boreholes and soil moisture sensors.

Final remarks

Christian mentioned that permafrost research offers quite some opportunities for meteorologists. Also, everyone enjoyed the great weather in the mountains.

Simona Lukosiunaite & Simon Reifenberg

 

University of Bern

September 17th

After an early breakfast in the youth hostel of Bern we started a walk to the University passing by the Federal Palace of Switzerland. At the University we met with Prof. Dr. Olivia Romppainen-Martius who guided us to the Institute of Geography. There we heard a talk about their work on Paleoclimatology and Paleoreanalysis. Their main goal is the understanding of climate variations in the past. To accomplish that they built a 3D model simulation for the past five centuries. The model is physically and statistically consistent and has a timestep size of one month. In the model they assimilated meteorological proxydata with the “Ensemble Kalman Fitting”-method. The proxydata goes back to the 15th century and includes tree rings, ship data, historic records, boreholes and sediments. Unfortunately, the quality of the proxydata varies significantly, since the measuring methods in the past centuries were not equally accurate. Also, for the southern hemisphere there is not very much data available.


Federal Palace of Switzerland

The second talk this morning was about the Mobiliar Lab for Natural Risks. The Mobiliar Lab is a collaboration between the Oeschger Centre for Climate Change Research and the insurance company Schweizer Mobiliar. Their research is dedicated to natural hazards in Switzerland such as hail, storm and floods and the evaluation of the risks of these hazards. Main point of the talk was their website about flooding risks in the different parts of Switzerland where the evaluation of flooding risks can be seen on a map and also be filtered by severity and amount of buildings involved. (https://schadenpotenzial.hochwasserrisiko.ch/de/map). A different part of the website includes the “Überschwemmungsgedächtnis”, which is a collection of pictures from past floods in Switzerland with the oldest entry from 1318 (https://ueberschwemmungsgedaechtnis.hochwasserrisiko.ch/de/home).

After that theoretical part we visited the satellite data receiving station at the roof of the university building. The data is received from NOAA weather satellites with an antenna, which is automatically aligned to the passing satellites. The data includes images from different spectral regions like IR or visible light with a resolution of about 1 km at swath centerline. Real-time data like snowfall, vegetation or lakes can be retrieved. The scientific interest in the long time series.

 

On the roof of the building is also a hail sensor. It consists of a plate with a microphone attached to it (and some spikes against pigeons). The microphone detects the sound of falling hail stones. The sound reveals information about momentum and energy of the hail stones. The sensor is driven by solar cells and is calibrated ones a year with chunks of frozen orange juice (apparently that’s the best way to artificially mimic the properties of actual hail stones). The sensor is part of a network of currently 11 sensors. In the future this network will be extended to 80 sensors.

 

 

 

Franziska Bär & Nicolas Emig

 

Paul Scherrer Institute

September 17th

Short summary

After visiting the University of Bern, we continued our journey to the Paul Scherrer Institute. After two hours of driving, we arrived at Villigen, a small town near Zürich, which hosts the largest research facility for natural and engineering science in Switzerland. At the entrance, we met Dr. Brem, our guide for the day. He brought us to a small room, where we listened to a presentation about the Paul Scherrer Institute. After a short coffee break, we went on to the Swiss Light Source, short SLS. After that, we took a short walk on the other side of the river and headed to the laboratory for atmospheric chemistry, where Dr. Gysel Beer, the group head of the research group of aerosol physics, welcomed us. He showed us an experiment on aerosol detection with a vacuum chamber. Later Dr. Gysel Beer introduced us to Dr. Bell, one of the scientists of LAC. At the end of our trip, we observed two different types of smog chambers.

About Paul Scherrer Institute:

The Paul Scherrer Institute PSI is the largest research institute for natural and engineering sciences in Switzerland, conducting cutting-edge research in three main fields: matter and materials, energy and the environment and human health. PSI employs 2100 people, with an annual budget of approximately CHF 407 Million, which is mainly financed by the Swiss Confederation. PSI is part of the ETH Domain, with the other members being the two Swiss Federal Institutes of Technology, ETH Zurich and EPFL Lausanne. The Paul Scherrer Institute is located in the Canton of Aargau, in the municipal areas of Villigen and Würenlingen on both sides of the River Aare.

Main areas of research

  • Matter and Materials
    Study the internal structure of a wide range of different materials. Results contribute towards a better understanding of processes occurring in nature and provide starting points in the development of new materials for technical applications.
  • Energy and Environment
    The goal of activities in the area is to develop new technologies to facilitate the creation of a sustainable and secure supply of energy, as well as an uncontaminated environment.
  • Health Care
    In this area, researchers are searching for the causes of illnesses and exploring potential treatment methods.

Synchrotron (SLS)

The dominant part of our visit was the synchrotron, known as SLS. Synchrotron Light Source (SLS) is a source of electromagnetic radiation (EM) usually produced by a storage ring, for scientific and technical purposes. The Swiss Light Source (SLS) at the Paul Scherrer Institute is a third-generation synchrotron light source. With an energy of 2.4 GeV, it provides photon beams of high brightness for research in materials science, biology, and chemistry. The facility has planned in 1991 and this project was later approved in 1997. The first light from the storage ring had seen on December 15, 2000, and as 2009, SLS has eighteen experimental stations.

Laboratory for atmospheric chemistry (LAC)


In the following part of our journey, we met Dr. Martin Gysel Beer, the Group Head of Aerosol Physics. The aim of the research group was analysing aerosol chemistry, as well as studying the physics of aerosols and molecular cluster and particle processes. In this laboratory, aerosol detection with the use of orange peels in a vacuum chamber has been experienced.

Smog chamber

The medium size (on the left) and the small size (on the right) Smog chambers were the last part of our visite, in Paul Scherrer Institute. The smog chambers in this institute were used to investigate chemical and physical processes related to air pollution under controlled conditions. They also did studies on oxidation mechanisms, particle nucleation, and organic aerosol formation and ageing.

In the end, after nearly three hours of visiting different parts of the institute, we headed to Zürich to rest and make our next day journey to ETH Zürich on 18 September 2019.

Navid Mouji & Jan Wallner

 

ETH Zürich

September 18th

After two productive days in Bern finally we derived to our second destination Zurich, we stayed at Hotel Olympia. At night we found a chance to discover our surrounding, for me this city is a combination of modernity and culture. Zurich is the largest city in Switzerland and it's located in northcentral. They speak  three national languages recognized in Switzerland: German, French and Italian. The society is highly valued education and intellectual people where born and worked there like Albert Einstein.

Next day we visited the ETH Zurich, one of the most famous and high ranking university in the word. This university was in 2018 - 7th overall in the world and also in 2015 - 5th in the world in Engineering, Science and Technology.

As planned we saw the Institute for Atmospheric and Climate Science (IAC) to get to know their activities and current researches. IAC is a part of the Department of Environmental Systems Science of the ETH. The IAC is active both in research and education. Research focuses on atmospheric and climate processes, including links to the hydrosphere, cryosphere, and biosphere. In the education IACET provider lecture courses, practicals and seminars.

As main part of we our visiting we listened to the presentations by:

  • Knutti, Reto, Prof. Dr., he leads the climate physics group and do research and teaching on many topics related to climate change.
  • Brunner Cyril and Friebel, Franz , research area Ice nucleation. The formation and evolution of clouds and precipitation and the impact on Earth's climate.
  • Wernli, Heini, Prof. Dr., head of of Atmospheric Dynamics at the Institute of Atmospheric and Climate Science in the Department of Environmental Sciences since 2009. He presented about the pathway of atmospheric water from ocean evaporation to rain out in extratropical weather system.

After a productive time in the institute and exploring around, Prof. Wernli invited us to have lunch in memorable and fancy ETH Mensa. Drinking a cup of coffee on the balcony and enjoying a panorama view of the city and networking about the future opportunities.

As summery I found the visit totally worthy and ETH Zurich is the one of most impressive locations we visited during this excursion. I would like to mention the prefect arranging and great hosting by Prof. Wernli. Finally at 2:00 PM we left ETH for last long journey to the Davos city.

Elaheh Bastani

 

PMOD/WRC

September 18th

After a relatively long busdrive from Zürich, we arrived in the small and nice town of Davos, where the Physical Meteorological Observatory Davos is located. The Building itself is actually quite small, which was kind of surprising, because it is also the World Radiation Center (WRC) since January 1970, as designated by the World Meteorological Organization (WMO).

Every five years, multiple scientists in the field of solar irradiance gather at the PMOD for the International Pyrheliometer Comparisons (IPC), in order to calibrate their measurement devices and exchange ideas. So, for the purpose calibration and standartization, the so called World Standard Group (WSG, Fig. 1) is located at PMOD, a collective of multiple pyrheliometers (some historical, but most of them are modern high precision devices). The next generation of pyrheliometers they have planned for the WSG are the so called CSAR, which stands for „Cryogenic Solar Absolute Radiometer“. This technology minimizes the measuring error by eliminationg the error sources of direct solar radiation and internal wire heating through vacuum isolation and internal cooling systems.

And this is what the PMOD is (mostly) about: high precision measurement of solar irradiance, development and production of high precision measurement devices (both for use on the earth and in space). An example for such a measurement device is CLARA, which stands for „Compact Light-Weight Absolute Radiometer“ , which is basically a low-cost micro-satellite, which is built for measuring the total solar irradiance (TSI). Despite it being smaller than it's preceding generations of TSI measuring devices, it is expected to deliver more precise data. For that reason, they are also involved in projects concerning questions about space weather and solar physics by the NASA and ESA.

 

So as you can see, it is a highly specialized institute, and they are basically the „world champions“ in their respective scientific field. At our short stay at the PMOD, our guide gave us a short presentation of these projects and tasks, and showed us around their various measuring devices, including the WSG.

While this was very impressive, I'm sad to say that this is not really a field I'm interested in, but in no way am I trying to belittle their work of standartization, development and production of their devices. I got the impression, that Davos is the „Mekka“ of measuring solar irradiance. So if you are interested in this scientific field, i can still recommend going to Davos and visiting the PMOD/WRC.

Florian Zanger

 

Snow and Avalanche Research Institute (WSL-SLF)

September 19th

On the last day of the excursion we visited the Snow and Avalanche Research Institute (WSL-SLF)
in Davos. The SLF was founded in 1942 and is responsible for the avalanche warnings in the swiss alps since 1945. His main purpose for the public is the release of avalanche-bulletins twice a day.
Besides this purpose the SLF focuses its research in the topics:

  • Natural hazards
  • Alpine ecosystems
  • Snow processes
  • Avalanches
  • Permafrost

The first talk was held by the climatologist Christoph Marty. He gave us a brief overview about the climate in alpine regions. The SLF has a network of 140 climate monitoring stations. Each of them measures the snow height through an ultrasonic range sensor. The diffuse and global radiation is measured with a pyranometer. The wind-speed and -direction is logged with a cup anemometer and the turbulent wind field is measured with an ultrasonic anemometer. And lastly the temperature is recorded with a thermometer.

Only 40 of these monitoring stations are automated and the rest are operated manually, which makes this process labour intensive. He proceeded to talk about climate change in the alps. Models predict that the snow line will get higher. And that melting events in the summer get more severe which effects the overall mass balance of snow.

After the talk we spent some time in the lobby, where snow related experiments are presented. For example, a replica of an automated monitoring station or a model of a powder avalanche. After an explanation of these experiments by Henning Löwe the head of the snow-physic department, he showed us the cold chambers of the SLF. The cold chambers are the heart of the snow-physics department. They are used to study snow-physics and the metamorphism of snow.

One of the cold chambers contains the snow breeder, which is an instrument capable of producing nature like snow. They also use a 3D-Tomograph inside a cold chamber to study micro-structure of snow. The main difficulty is the transportation of snow samples from the measurement site to the laboratory. During the transport the snow undergoes metamorphisms which would alter the sample unnaturally. Hence a special device is used to solve this problem.

The 3D scans (see Figure) are compared with results of numerical models. From this data better parameterizations are developed and used in models like the Snowpack.
Finally, we attended a talk of Benjamin Walter who is a post-doc in the snow-physics department. One of his fields of interest is snowdrift.

Windblown snowdrift is an important process especially in Antarctica. Due to strong winds in the polar winter great amounts of snow are transported over long distances. Basic concepts are adopted from the modeling of sand drift in deserts.

The Snowpack-1D model is used to simulate the micro-physical structure of snow. Special attention is paid to the development of depth hoar. Depth hoar are big, cup-like crystals and due to their shape, they contain air pockets. This leads to weak bounds within the depth hoar layer. The formation is driven by large temperature gradients. For example, a thin snow layer will insulate the lower layers of the snowpack and the temperature is 0 °C. During a cold night at -20 °C a temperature gradient of 20 °C within this thin layer will lead to the development of depth hoar. Due to the weak bonds this layer will be prone to collapse if additional weight like a skier is added on top of it and hence increases the avalanche danger.

The presentation was finished with a short overview of the evolution of measurement devices. For example, the common method to get information about the snowpack is to dig snow-pits, which is a very slow and elaborate process. A measuring instrument was developed, consisting of a metal rod, which is forced into the snow. From the pressure resistance and the temperature snow properties can be derived.

Michael Debertshäuser & Sören Schmitt