IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group II: Impacts, Adaptation and Vulnerability

15.8 Key uncertainties and research priorities

Significant advances in our understanding of polar systems have been made since the TAR (Anisimov et al., 2001) and the Arctic Climate Impacts Assessment reports (ACIA, 2005). Many climate-induced changes that were anticipated in the TAR have now been documented. This validation, together with improved models, new data and increasing use of indigenous and local knowledge, has increased our confidence in projecting future changes in the polar regions, although substantial uncertainties remain, and the remote and harsh environments of the polar regions constrain data collection and mean that observational networks are sparse and mostly only recently established. The difficulty in understanding climate-change effects in polar regions is further exacerbated by the complexity within and among polar systems, their feedbacks and sensitivity, and their potential to switch into different states of (dis)equilibrium.

Significant research since the TAR has focused on the impact of climate change on Arctic indigenous populations, and accordingly, this chapter has placed an emphasis on these segments of the population. However, the impacts on the wider population need also be considered, and in particular, the economic impacts, which are difficult to address at present due to the dearth of information.

To address the key uncertainties, particular approaches will be required (Table 15.1). For the Arctic, detailed recommendations for future research have been drafted by the international scientific community (ICARP II, 2006), and a burst of co-ordinated research at both poles is anticipated during the International Polar Year, 2007-2009.

Table 15.1. Key uncertainties and related scientific recommendations/approaches.

Uncertainty Recommendation and approach 
Detection and projection of changes in terrestrial, freshwater and marine Arctic and Antarctic biodiversity and implications for resource use and climatic feedbacks Further development of integrated monitoring networks and manipulation experiments; improved collation of long-term data sets; increased use of traditional knowledge and development of appropriate models 
Current and future regional carbon balances over Arctic landscapes and polar oceans, and their potential to drive global climate change Expansion of observational and monitoring networks and modelling strategies 
Impacts of multiple drivers (e.g., increasing human activities and ocean acidity) to modify or even magnify the effects of climate change at both poles Development of integrated bio-geophysical and socio-economic studies 
Fine-scaled spatial and temporal variability of climate change and its impacts in regions of the Arctic and Antarctic Improved downscaling of climate predictions, and increased effort to identify and focus on impact ‘hotspots’ 
The combined role of Arctic freshwater discharge, formation/melt of sea ice and melt of glaciers/ice sheets in the Arctic and Antarctic on global marine processes including the thermohaline circulation Integration of hydrologic and cryospheric monitoring and research activities focusing on freshwater production and responses of marine systems 
The consequences of diversity and complexity in Arctic human health, socio-economic, cultural and political conditions; interactions between scales in these systems and the implications for adaptive capacity Development of standardised baseline human system data for circumpolar regions; integrated multidisciplinary studies; conduct of sector-specific, regionally specific human vulnerability studies 
Model projections of Antarctic and Arctic systems that include thresholds, extreme events, step-changes and non-linear interactions, particularly those associated with phase-changes produced by shrinking cryospheric components and those associated with disturbance to ecosystems Appropriate interrogation of existing long-term data sets to focus on non-linearities; development of models that span scientific disciplines and reliably predict non-linearities and feedback processes 
The adaptive capacity of natural and human systems to cope with critical rates of change and thresholds/tipping points Integration of existing human and biological climate-impact studies to identify and model biological adaptive capacities and formulate human adaptation strategies