Key Cryospheric Hazards and Risk Revision

What is the definition of a hazard?

A dangerous phenomenon, substance, human activity or condition that may cause loss of life, injury or other health impacts, property damage, loss of livelihoods and services, social and economic disruption or environmental damage

What is the definition of vulnerability?

The susceptibility of people, communities or regions to natural or technological hazards through three key dimensions of economic, social and ecological vulnerability; a description of the characteristics and circumstances that increase susceptibility to hazards

How is risk calculated?

Risk = hazard potential x exposure x vulnerability; this combines the probability of an event and its negative consequences to calculate the potential loss of life, injury or destroyed or damaged assets which could occur to a system, society or community in a specific period

What is the definition of cryospheric hazards?

Events, which can threaten humans and their welfare, that are caused by or related to cryospheric processes and changes in the atmosphere, ocean and land

What are the future trends in the cryosphere and associated hazards?

The cryosphere is shrinking but cryospheric hazards are likely to increase in a warming climate; hazards will be amplified in the Holocene

What are key atmospheric cryosphere hazards?

Frost, hail, freeze rain, extreme weather events

What are the impacts of atmospheric cryosphere hazards?

Serious economic losses due to impacts on agricultural production, transportation and electricity as well as human health and wellbeing

What are key oceanic cryosphere hazards?

Sea ice, icebergs, coastal erosion, sea level rise, subsea permafrost

What are the process and impacts of sea ice hazards?

Arctic sea ice is significantly decreasing due to increased temperatures and lower albedo feedback, this leads to flooding and coastal retreat; decline of infrastructure, blocking of sea routes and changing salinity of seawater with impacts to fisheries and mariculture

What are the process and impacts of ice berg hazards?

Small icebergs drift in unpredictable manners; they can collide with maritime trade, lead to sinking, loss of life and assets, block entrance of penguins to the sea etc.

What are the process and impacts of sea level rise hazards?

Major contributions to sea level rise come from glaciers and ice sheets which large acceleration in these trends; this leads to inundation of low lying land, coastal flooding etc.

What are key land cryosphere hazards?

GLOFs, glacier collapse, rock-ice avalanches, surging, debris flow, volcanism

What are the process and impacts of rock-ice avalanche hazards?

Changing climate leads to thinning and area decline of glaciers which leads to stress redistribution (debuttressing) and slope instabilities, degraded permafrost can also allow meltwater to penetrate joints and form mass movements driven by the presence of granular ice and water in the flow increasing mobility and the travel distance of the avalanche; this can lead to loss of life and destruction

Where and when was a catastrophic ice-rock avalanche evidenced?

Kolka Glacier in southern Russia saw almost the entire mass detach from the bed in 2002 and accelerate to a high velocity of up to 80m/s over 19km; this was a response to shifting ice and debris loading over months leading to detachment from the bed

Where, when and why have clustered rock-ice avalanche events occurred?

At the Petra Pervogo range in Tajikistan, 17 avalanches have occurred between 1973 and 2019 due to glacier instabilities stemming from early erodible soft lithologies paired with rising temperatures; potential energy becomes transformed into kinetic and frictional heat to enhance mobility with water as a key factor in reducing basal friction and ice melt leading to detachment which tends to occur in summer and years with high annual air temperatures

Where have many deaths been linked to rock-ice avalanches and glacier/permafrost related hazards, how is this changing?

In the extratropical Chilean and Argentianian Andes nearly 200 deaths have been related to the increasing frequency of GLOFs, rock-ice avalanches ad lahars due to recession and thinning of glaciers and permafrost destabilisation of slopes; vulnerability is increased through the use of glacial belts for mining, hydropower and tourism

What are the process and impacts of surging hazards?

The glacier speeds up and drops back down to normal flow, often due to dynamic instability including switches in the thermal or hydrological regime; this can lead to loss of life and infrastructure when glaciers surge unexpectedly

What are the process and impacts of debris flow hazards?

These are often related to glacier melting and GLOFs leading to the entrainment of trees, ice, rocks and boulders in meltwater; this can cause causalities and damage to infrastructure

What are the process and impacts of glacially induced volcanic hazards?

There are theories that large scale deglaciation may be responsible for triggering seismicity and volcanism due to change stresses on the lithosphere that may induce upward movement of magma and trigger slipping

What are the key snow and permafrost hazards?

Heavy snowfall, snow avalanches, snowmelt floods, permafrost creep, degredation, thermokarst, thaw slumps, active layer detachment

What are the process and impacts of permafrost hazards?

Permafrost degradation can destabilise mountain slopes, land bearing capacity, increase risks of landslides and avalanches and have biogeochmiecal threats to ecosystems and human health

What is thermokarst and what are the impacts of this process?

Permafrost thaw that leads to slumps of land including thaw slumps, thermo-erosion gullies and active layer detachments; this threatens ecosystems, infrastructure and cultural heritage sites

Where is the impact of slope failures evidenced and how is this modelled?

In Northern Alaska there is increased incidence of permafrost degradation leading to thaw slump and active layer detachments; a data-driven model was used to map areas prone to land failure into a multi-hazard susceptibility map that was useful in tailoring local strategies to mitigate against damage and highlighting in the role of unconsolidated materials, temperature and snow cover in the incidence of these hazards

Where is the impact of thaw slump and erosion gullies evidenced and how is this modelled?

At the Svalbard Archipelago cyrosphesic hazards continue to develop as a result of thermokarst; data-driven models were used to form multi-hazard susceptibility maps to reveal the factors that drove processes and identify high risk areas as a tool for urban planning and risk management to protect heritage sites, infrastructure and ecosystems

Where has the reduced bearing capacity of permafrost been evidenced?

In a 2020 oil tank collapse in Norilsk, Russia leading to 21,000 cubic metres of diesel oil split onto the surrounding environment

Where has the water system interaction with permafrost been evidenced?

There have been complete water failure systems in Point Lay and Wainwright, Alaska leading many homes, buildings and a health centre to go without water; since 2009 drinking water sources have been contaminated and drained