The field sites have been selected to cover a wide range of environmental conditions and to offer the best available platforms for the validation of large scale models, the development of permafrost monitoring capabilities, the study of permafrost processes, and for overlap with existing monitoring programs. Site selection was also driven by the necessity to focus on the smaller number of field sites that are able to provide a comprehensive range of monitoring parameters for the validation of Global Climate Models (GCMs) across the Arctic permafrost areas.
While many sites in the Arctic are equipped to record active layer, and some upper permafrost layer, temperatures or gas fluxes, only a small number of these have the longer observation records that will enable the PAGE21 project to derive the maximum benefit from earlier programs and to include temporal variability in Arctic ecosystems in a consistent way.
The sites selected for PAGE21 fulfil the latter conditions and are often embedded in existing monitoring networks such as the Circumpolar Arctic Layer Monitoring (CALM)
program, the Circumarctic Network of Terrestrial Field Bases (SCANNET
, through the EU-funded INTERACT
application), or the upcoming Sustaining Arctic Observing Networks (SAON
), taking advantage of funded initiatives to conduct permafrost monitoring at these sites. The PAGE21 project sites are, for instance, supported through other initiatives such as DEFROST
(Nordic Centre of Excellence, in the Cryosphere Programme of the Nordic Council of Ministers), and the ESA DUE Permafrost
project. PAGE21 is unique in that it does upgrade these sites to cover most aspects of monitoring relevant to permafrost and it connects them systematically to model outputs.
The PAGE21 sites span the whole spectrum of conditions observed in the Arctic, starting with the sporadic permafrost zone in the sub-Arctic (Abisko) and extending to the continuously cold permafrost zone (Kytalyk). The sites also cover different geographical zones of the Arctic, with sites on each of the three landmasses (North America, Greenland and Europe/ Russia) surrounding the Arctic Ocean, and include maritime as well as continental locations.