Most human activity in the Arctic takes place along permafrost coasts, making them a key interface. They have become one of the most dynamic ecosystems on Earth because permafrost thaw is now exposing these coasts to rapid change: change that threatens the rich biodiversity, puts pressure on communities that live there and contributes to the vulnerability of the global climate system. NUNATARYUK will determine the impacts of thawing coastal and subsea permafrost on the global climate, and will develop targeted and co-designed adaptation and mitigation strategies for the Arctic coastal population. NUNATARYUK brings together world-leading specialists in natural science and socio-economics to: (1) develop quantitative understanding of the fluxes and fates of organic matter released from thawing coastal and subsea permafrost; (2) assess what risks are posed by thawing coastal permafrost, to infrastructure, indigenous and local communities and people’s health, and from pollution; (3) use this understanding to estimate the long-term impacts of permafrost thaw on global climate and the economy. NUNATARYUK will be guided by a Stakeholders’ Forum of representatives from Arctic coastal communities and indigenous societies, creating a legacy of collaborative community involvement and a mechanism for developing and applying innovative evidence-based interventions to enable the sustainable development of the Arctic.

The objective of the Copernicus Cal/Val Solution (CCVS) is to define a holistic solution for all Copernicus Sentinel missions (either operational or planned) to overcome current limitations of Calibration and Validation (Cal/Val) activities. Operational Cal/Val is required to ensure the quality of and build confidence in Copernicus data. However, these activities are currently limited by the following considerations: • The requirements and objectives need to be revisited to consider new usage of Copernicus products, inter-operability requirements, and to anticipate the needs of future Copernicus missions • Current Cal/Val activities are constrained by programmatic and budgetary requirements and do not necessarily follow scientific priorities • Cal/Val activities depend on the operational availability of high-quality Fiducial Reference Measurements (FRM) which are today mostly provided by external entities without strong commitment to the Copernicus program • Synergies within Copernicus and with other national and international programs are not systematically explored. To address these limitations CCVS will propose: • An updated specification of Cal/Val requirements for the Sentinel missions, taking into account inter-operability needs • An overview of existing Calibration and Validation sources and means • A gap analysis identifying missing elements and required developments in terms of technologies and instrumentation, Cal/Val methods, instrumented sites and dissemination service. • A comprehensive Copernicus Cal/Val Solution to organize the long-term provision of FRM for Sentinel missions • A roadmap documenting how the Cal/Val Solution can be implemented, highlighting responsibility, cost and schedule aspects. This plan will be elaborated in concertation with all stakeholders through four Working Groups gathering European Space Agencies, Copernicus Services, measurement networks and International partners.