The impact on snow and ice of rapid changes in the Arctic
Leader: John Moore Start of the project: 1999
Research group: Global changeEnd of the project: 2002
|We have investigated the changes in the glaciers in Svalbard using ground penetrating radar to study their internal structure and thickness. Glaciers were surveyed by using geodetic GPS to determine how they have changed using data from surveys carried out in 1900 and 1936. We observe a general thinning, such that several important glaciers may disappear within 80 years. We have also investigated the hydrology of the glaciers and made mathematical models of their internal water storage and flow systems.
We have used an ice core the Lomonosovfonna ice cap to study the composition of the atmosphere over the last 800 years. This ice core is the best available from the Barents region - an important area for the climate of Europe. We have observed large increases in levels of man-made acidity since 1850 - much earlier than observed in central Greenland. We have also investigated many other chemical impurities in the ice core that tell the story of sea ice the Barents sea and the primary biological productivity of the area, the variation in snow fall over the last 300 years and the variability in climate between the Little Ice Age and the present day climate.
Research and results
One of the main outcomes has been the completion of the analysis of the deep Lomonosovfonna ice core, drilled in 1997. This core represents the best record we have from the Svalbard area of past climate and anthropogenic influence on the region for the past 500 years. This is very complimentary to records obtained in Greenland and Antarctica, but because of the close proximity to Northern Europe, tells a higher resolution story covering the period of European industrialization.
Teija Kekonen completed the Lomonosovfonna ice core major ion analysis using a new Dionex HPLC system. This required a great deal of ice core sample preparation. We also developed a new clean laboratory at Rovaniemi Metla.
| Detailed studies of the chemistry record indicate:
• The levels of sulphate in the core start to rise above background levels as early as 1850. This is new finding that has not been observed at sites such as Greenland.
• Nitrate also shows a rise beginning at the start of the 20th Century, that accelerated in the 1950s.
• PAHs show levels intermediate between Greenland and Canadian Arctic.
• MSA seems to be directly related to sea ice in the Barents Sea
• Ions and isotopes in the ice core preserve an almost annual resolution, certainly the best record available from Svalbard
• The temperature profile in the borehole reveals temperatures today are 2C higher than the 19th Century
• Accumulation rates have varied by about 20% over the last 300 years, with much higher accumulation since 1950.
The main results of the glacier surveys are:
• Many glaciers of Southern Spitsbergen have been surveyed for both surface elevation and volume.
• Many of the glaciers show great retreat and decay since accurate surveys were made in 1900 and 1936.
• The large glaciers of Hornbreen and Hambergbreen that currently form a continuous glacier between Sörkappland and the main land will likely disappear in the next 100 years due to rising temperatures
• The valley between they occupy will become a partially inundated isthmus, but still have a continuous land bridge above sea level.
• The polythermal glaciers in Svalbard are characterized by extensive superimposed ice zones that can be mapped using remote sensing methods such as radar.
• The hydrology of these glaciers is dominated by high water pressure systems in large stable conduits, the pressure being maintained by periodic blocking of channels by sediments.
• Uppsala University, Sweden (Ice core analysis)
• Norwegian Polar Institute, Norway (Svalbard logistic support)
• University of Utrecht, The Netherlands (Ice core drilling)
• Tallinn Technical University, Estonia (Mass spectometry of oxygen isotopes)
• Centre of Isotope Research. Groningen, The Netherlands (Mass spectrometry deuterium isotopes)
• LGGE Grenoble, France (Radio- isotope analysis)
• University of Silesia, Poland (Geomorphology and surveying of glaciers)
• Academy of Sciences, Poland (Logistics support in Svalbard, radar and GPS glacier surveying)
Senior Scientist John Moore
Arctic Centre, University of Lapland