In Depth Coverage

Modelling and monitoring mountain permafrost in the Russian Altay Mountains

The Earth's climate has changed many times during the planet's history, with events ranging from ice ages to long periods of warmth. Historically, natural factors such as volcanic eruptions, changes in the Earth's orbit, and the amount of energy released from the Sun have affected the Earth's climate. Beginning late in the 18th century, human activities associated with the Industrial Revolution have also changed the composition of the atmosphere and therefore very likely are influencing the Earth's climate.

For over the past 200 years, the burning of fossil fuels, such as coal and oil, and deforestation have caused the concentrations of heat-trapping "greenhouse gases" to increase significantly in our atmosphere. As the concentrations of these gasses continue to increase in the atmosphere, the Earth's temperature is climbing above past levels.

This climate change is affecting our cultural heritage and in particular the well known 'frozen tombs of Altai' where we now need the assistance of earth observation from space in order to, with support of field work, be able to derive information to assist UNESCO and conservation authorities in understanding where permafrost might be disappearing

• Link With Climate Change

  Open

  Recently, the frozen context of the structures becomes more and more important as global warming might affect the preservative conditions of the permafrost. Particularly future climate models predict a 2 degree global warming throughout the 21st century. As a result a significant global retreat of glaciers and degradation of permafrost is expected. As great parts of the Russian Altai Mountains are located in such areas of continuous and discontinuous permafrost, they are extremely vulnerable towards a possible temperature increase.

• Objectives

  Open

  The interest for the area is mainly caused by the very rich archaeological context of the mountains. Several cultures occupied the area, dating back as far as 4000 BC. The most remarkable of all these, are the so-called Scytho-Siberians, who lived in the Altay between the 8th and 2nd century BC. This culture is most known for their special graves (called 'kurgans'), which consist out of a burial chamber covered by a stone heap. Due to the ground temperature lowering effect of this blocky surface, next to the fact that these kurgans are located in zones of permafrost, are some of these graves, and their content, exceptionally well preserved. This results in excavations where mummies with intact skin parts and tattoo's are found.
  
  To take preservation measures, regarding the frozen kurgans, a detailed permafrost map of the area is first needed. Therefore, to estimate the current permafrost distribution, our project 'Modelling mountain permafrost in the Altay Mountains', was recently started up together with UNESCO.
  
  Summarized, these are the goals of our project:
  - Estimate the current permafrost distribution in the Russian Altay Mountains
  - Calculate the current ground thermal regime of the different kurgans in the area, regarding their topographic position and dimensions
  - Calculate the evolution of the permafrost area during the last 30 years.
  - Determine future scenarios based on IPCC-climate prognosis for the 21st century.
  - Assess the vulnerability of the kurgans in the area, and calculate their "defrost-point".

• Technical and Scientific Approach & Methods Proposed

  Open

  Due to the very remote and vast character of the area, traditional modelling techniques offer no solution. As an alternative, we developed a strategy based on remote sensing techniques, statistical analysis and numerical modelling. This strategy is mainly based on thermal remote sensing imagery provided by ASTER and MODIS, however detailed vegetation and landcover data is still needed for modelling purposes. As cloudfree summer ASTER-images are limited, the availability of SPOT imagery would be a major help to determine landcover and vegetation characteristics in the area. This is necessary because vegetation plays a major role in the energy balance at surface, and therefore a detailed landcover map of the area is used to calculate subsurface heat-fluxes. By using this strategy we hope to meet the goals of our project as mentioned above.
  
  Next to the contribution of SPOT imagery to vegetation and landcover mapping, we will also try to use the 2.5 m multispectral images in the Ulandryk valley to see if these images can be applied to map kurgans, as it's essential to locate all these structures. This method is based on the spectral contrast between the stony kurgan and its vegetated surroundings, which might be visible on the 2.5 m resolution images.

• Local Actions

  Open

  - To collect soil surface temperature
  - To install additional air temperature logging devices, to dense the network of mountain meteo-stations
  - To install a spatial network of temperature dataloggers, as well as different vertical temperature profiles (kurgans)
  - To take ground control points to further assist the satellite image processing.
  - To investigate the distribution of different active periglacial surface phenomena, and periglacial remnants.
  - To create a local capacity among the researchers of the partnership institution Gorno Altaisk State University in the area of permafrost assessment.
  - To take sample areas, to make supervized classification based on remote sensing possible

• Region Name

  Open
  Altai Region

• Partners involved in project

  Open
  - Ghent Unsiversity (UGent),
  - UNESCO,
  - Gorno Altaisk State University (GASU)