Glacial hazards research and monitoring: first and second years of the project

Mountain glaciers are among the most spectacular features of alpine landscape, a target for recreation, and an important freshwater source, especially for some arid and semiarid regions. However, they also bring destructive natural hazards. Global warming leads to dramatic and accelerating shrinkage of alpine glaciers around the world since the end of the Little Ice Age (mid-19th century), and most glaciers have retreated by up to a few kilometers. After the termini of the glaciers retreat the vacant areas are occupied by moraine (glacier-created) debris and proglacial lakes, usually dammed by unstable moraines or stagnant ice. In comparison with other glacier hazards, glacier lake outburst floods (GLOFs) are most widespread and highly recurrent. The deadliest GLOF happened in Huaraz, Peru in 1941 and killed about 5000 people. In the Alps up to 60% of the victims of glacial hazards were killed by GLOFs and consequent debris flows. In summer 1998 an unexpected GLOF in Kyrgyzstan and Uzbekistan (Central Asia) killed over 100 people. Frequency of GLOFs is increasing in the majority of alpine ranges worldwide. Rate of proglacial lake increase could be quite high, with their diameters growing by some hundred meters per year in extreme cases. Often local population learns about the very existence of a proglacial lake after it has produced GLOF event. Location and size of new lakes, their current state and hazard potential could shift rapidly. In combination with rapid growth of population and economic development it means a high GLOF hazard for communities downstream of the lakes. Regular monitoring of periglacial environment is needed to identify most vulnerable zones, reduce and mitigate GLOF risk, prevent life losses and minimize economic losses.

All of the above is true for the Caucasus, a highly glaciated mountain range up to 5642m a.s.l. set between the Black Sea in the west and the Caspian Sea in the east, between Russian in the north and Georgia & Azerbaijan in the south. In the last 20 years glacial hazard assessment here was scarce due to the difficult transition period in the 1990s and the resulting lack of funding. Early in the new millennium unpredicted glacier hazards caused over 100 casualties, significant economic losses (about 100 million Euro) and brought tensions between the suffering local population and authorities in the Russian Central Caucasus. Glacial hazard assessment in the region was badly needed.

With enthusiastic support of the Ministry of Emergencies offices in the Kabardino-Balkaria and Northern Ossetia-Alania Republics, an international consortium of scientists from Moscow, Russia, and from Waterloo and Vancouver, Canada, have started a project on PREDICTION OF GLACIAL HAZARDS AND DISASTERS IN THE CENTRAL CAUCASUS, RUSSIA, supported by the NATO SfP Programme. Since in the near future GLOF events are expected to make the main contribution to glacial hazards in the region, one of the first tasks was to identify most dangerous objects by making a regional proglacial lake inventory. About 70 proglacial lakes were identified in the Central Caucasus, some of them potentially hazardous. A map of debris flow and glacial hazards for the region has been also compiled.

Further work was directed in three main areas. Firstly, two key areas of progalcial lakes, to the north of Mt. Elbrus (the upper Malka River valley) and 20 km south-east of Mt Elbrus (the Adyl-su river valley), were researched as the most hazardous areas. Lake area increased there by 3 to 6 times in recent decades. A GLOF in the first area was successfully predicted by the project team, helping to avoid casualties. The hazard in the second area is still growing, and a monitoring and early warning system is operating there since 2008.

Secondly, a summer service of �debris flow and glacial hazard watch� was organized for the Russian Central Caucasus: from 2006, project end-users and local authorities receive timely information from the project field teams in June-September, with regard to current level of the hazard; field teams investigate fresh debris flow deposits and made short term hazard forecasts. Thirdly, the project teams are maintaining monitoring of the site of Kolka Glacier catastrophic event (which killed over 125 people in 2002 due to a sudden glacier collapse), advising local residents and authorities on the current hazardous processes and build-up of new glacial material in place of the former glacier.

In terms of reducing the current hazard, the project work at key sites of proglacial lakes has been perhaps the most significant.

The first site is in a wilderness area just below the 3-km glaring-white north wall of Mt. Elbrus, the highest mountain of Europe (5642 m a. s. l.). The lakes near glacier boundaries are on a high plateau above the semiarid mountain steppes of the foothills. Rich herds are grazing upon the steppes. Local thermal springs bubbling a few kilometres downstream of the proglacial lakes are well-known in the Caucasus. Mountain dwellers attribute miraculous curative qualities to these waters, and hundreds of them come every year to bathe in little stone pools, erected right on a floodplain at the confluence of Birdzhaly-Su and Kizilkol rivers, with a view to 25-m high Sultan waterfall.

In 2006 the project team was measuring water volume in proglacial lakes, and assessing GLOF hazard and risk-prone zones. Rainy and foggy weather and icy mornings accompanied the expedition which did not seem to find high hazard. However, when the last and largest lake was surveyed, unalarming news was broken: the 400,000 cubic meters of lake water were nearly overflowing its ice dam, with only an 80-centimeter high icy barrier above the water still keeping the lake in place. The trajectory of the future outburst flood was clearly along the Birdzhaly-Su River, straight through the thermal pools, where up to 50 people could be in the hazard zone. The GLOF was nearly imminent: the project team concluded that it will happen within two weeks given the regional melt rates for glacier ice, the values well known to the project team. The local administration, the Ministry of Emergencies and the regional government were warned, and when the GLOF did happen exactly 5 days later, there were no casualties, though the pools were thoroughly destroyed and buried by 2 meters of mud and boulders. The lake which produced the GLOF was nearly emptied; monitoring visits in 2007 and 2008 identified that despite the current growth of the lakes none of them as yet presents significant hazard.

The second site of a potential GLOF is located in the Adyl-Su valley in the southern part of Mt Elbrus region. A group of proglacial lakes has formed in the headwaters of Adyl-Su river catchment area, near the margin of Bashkara Glacier. The biggest lake, called Bashkara, was almost stable in size for many years, and its GLOF hazard was assessed as medium. Since 2007 the glacier dam below the lake has been actively degrading, and in 2008 the seasonal lake level rise was much higher than normal. This can result in a GLOF and a devastating debris flow downstream (a similar event occurred at this site in late 1950s).

To reduce the risk the project team installed a self-designed automatic early warning system. In case of sudden drop of the lake level a siren is activated giving about 20 minutes warning. In addition, four warning poster boards were established on the trails and at the camp site in the danger zone. The project team also started constant observations of the lake, and provided real-time information in response to numerous calls from the Ministry of Emergencies, local authorities and citizens. By mid-July water started to overflow the dam started and outburst probability became very high. Close cooperation with the Ministry of Emergencies and local authorities led to good awareness of mountain dwellers and tourists. One of hotels was closed, the Ministry of Emergencies received daily hazard assessments and brought its own observers on the site. Luckily, the overflow stream has stopped and in the end of August the situation was stabilized.

Unique data and experience were obtained by this first monitoring and early warning system for GLOF hazard in Russia. The system has been designed and successfully applied, and will be deployed again in the operational mode in 2009.

Dozens of students have been trained during the project both in the field and in the laboratories. Three students obtained their PhDs during the project and three more are working on their PhDs.

Glacial hazard assessment is an important contribution to population security in alpine regions. Within the framework of this NATO SfP project the assessments have been made for the Russian Central Caucasus, but for many other regions of the world glacial hazard these assessments are badly needed. In poor mountain regions economic and life losses caused by natural hazards are often assessed by dwellers as inability of authorities to improve their life, sometimes leading to tensions and even separatist tendencies. Therefore environmental and political securities are closely linked.

Glacial environment is possibly the most rapidly changing landscape of the globe, so hazard assessment has to be repeated at least each 3 to 5 years. This can be helped by latest technologies, such as interpretation of very detailed satellite imagery, and by training of local experts and young scientists in such SfP projects as the one exemplified above.

Further information is available at the project website at
http://glacier-hazard.narod.ru/sfp.htm