Arctic environmental security and abrupt climate change - Environmental and Human Security in the Arctic - page 107

effect that would have substantial effects on climate change globally. Moreover,
release of marine hydrate deposits would accelerate the release of CH 4 from
northern permafrost, amplifying a process that, by itself, would be unlikely to
trigger abrupt climate change. One outstanding problem is that the research
into carbon releases in the Arctic is fairly new, and it will likely take years
for conclusive research to establish the thresholds for methane hydrates.
Whether such thresholds may have already been crossed by the time that the
research becomes conclusive is another question, and one that must be posed
to policymakers. These potential events in the Arctic (Greenland melting,
Arctic sea ice, methane releases) were not included in the 2007 IPCC report
as potentially significant influences of feedbacks in the global climate (IPCC
2007:372). Consequently, they are also missing from more recent security
reports on climate change, which rely almost entirely on IPCC data to sub-
stantiate potential risks and to estimate future conditions.
Tipping points, cascading effects and impacts
Once the initial tipping points in certain systems are better understood, and
certain abrupt change scenarios can be played out in terms of possible events,
we can assess the potential impacts on various related systems globally. The
cascading effects enter where change in one system (e.g. the Greenland ice
sheet) results in conditions (rapid rise in sea levels) that have varying impacts
elsewhere depending upon the vulnerability of the geographic region (e.g.
sensitivity to flooding from low-lying coastal land), social systems (resilience
to forced migration) and economic systems (fragility of infrastructure), all
applied at scalable levels and according to analytical needs. Disruptions in
social and economic systems then have their own cascading effects on related,
complex systems.
Ecological systems
Abrupt changes in climate conditions have immediate impacts on environ-
mental systems. Such abrupt shifts have occurred in the geologic past, forcing
changes in habitable zones for flora and migratory routes for fauna, although
the extent of human habitation and terraforming (e.g. land changes from agri-
cultural or urban development) may severely restrict the ability of ecological
systems to adapt to changing conditions. Ecologists predict that abrupt cli-
mate changes will result in accelerated extinction rates around the globe,
potentially destabilizing ecosystems if keystone species (i.e. those essential to
ecosystem stability) are lost. As ecosystems are already under severe pressure
from habitat loss, shifts in temperature, rainfall and habitable zones will only
worsen already vulnerable ecosystems.
The loss of ecosystems is not merely a matter of species loss, but represents
an instability that will impact human-related systems. Human vulnerability