ICAR: endoscopic skull‐base surgery

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Arctic Cryosphere: Changes and Impacts

The Arctic cryosphere is a critically important component of the earth system, affecting the earth's energy balance, sea level, greenhouse gases and atmospheric circulation, transport of heat through ocean circulation, ecology and human resource use and well-being. The Arctic cryosphere is, however, changing rapidly with multiple important consequences that will potentially affect the earth system including the human population. The drivers of changes in the Arctic's cryosphere, the recent and projected changes in the cryosphere and the consequences for future climate warming, sea level rise, ecology and human well-being, have been comprehensively assessed by the Arctic Council's Snow Water, Ice, and Permafrost in the Arctic (SWIPA) Project through its Arctic Monitoring and Assessment Programme Working Group. This article introduces the assessment and the associated papers within a special issue of the journal Ambio that extract and present some of the major findings of the SWIPA report

The Changing Arctic Cryosphere and Likely Consequences: An Overview

The Arctic cryosphere is a critically important component of the earth system, affecting the energy balance, atmospheric and ocean circulation, freshwater storage, sea level, the storage, and release of large quantities of greenhouse gases, economy, infrastructure, health, and indigenous and non-indigenous livelihoods, culture and identity. Currently, components of the Arctic cryosphere are subjected to dramatic change due to global warming. The need to document, understand, project, and respond to changes in the cryosphere and their consequences stimulated a comprehensive international assessment called “SWIPA”: Snow, Water, Ice, Permafrost in the Arctic. Some of the extensive key SWIPA chapters have been summarized and made more widely available to a global audience with multi-disciplinary interests in this Special Report of Ambio. In this article, an overview is provided of this Special Report in the context of the more detailed and wider scope of the SWIPA Report. Accelerated changes in major components of the Arctic cryosphere are documented. Evidence of feedback mechanisms between the cryosphere and other parts of the climate system are identified as contributing factors to enhanced Arctic warming while the growing importance of Arctic land-based ice as a contributor to global sea-level rise is quantified. Cryospheric changes will result in multifaceted and cascading effects for people within and beyond the Arctic presenting both challenges and opportunities

Polychlorinated biphenyls (PCBs) as sentinels for the elucidation of Arctic environmental change processes:a comprehensive review combined with ArcRisk project results

Abstract Polychlorinated biphenyls (PCBs) can be used as chemical sentinels for the assessment of anthropogenic influences on Arctic environmental change. We present an overview of studies on PCBs in the Arctic and combine these with the findings from ArcRisk—a major European Union-funded project aimed at examining the effects of climate change on the transport of contaminants to and their behaviour of in the Arctic—to provide a case study on the behaviour and impact of PCBs over time in the Arctic. PCBs in the Arctic have shown declining trends in the environment over the last few decades. Atmospheric long-range transport from secondary and primary sources is the major input of PCBs to the Arctic region. Modelling of the atmospheric PCB composition and behaviour showed some increases in environmental concentrations in a warmer Arctic, but the general decline in PCB levels is still the most prominent feature. ‘Within-Arctic’ processing of PCBs will be affected by climate change-related processes such as changing wet deposition. These in turn will influence biological exposure and uptake of PCBs. The pan-Arctic rivers draining large Arctic/sub-Arctic catchments provide a significant source of PCBs to the Arctic Ocean, although changes in hydrology/sediment transport combined with a changing marine environment remain areas of uncertainty with regard to PCB fate. Indirect effects of climate change on human exposure, such as a changing diet will influence and possibly reduce PCB exposure for indigenous peoples. Body burdens of PCBs have declined since the 1980s and are predicted to decline further