Eroding permafrost coasts release low amounts of dissolved organic carbon (DOC) from ground ice into the nearshore zone of the Arctic Ocean

Ice-rich permafrost coasts in the Arctic are highly sensitive to climate warming and erode at a pace that exceeds the global average. Permafrost coasts deliver vast amounts of organic carbon into the nearshore zone of the Arctic Ocean. Numbers on flux exist for particulate organic carbon (POC) and total or soil organic carbon (TOC, SOC). However, they do not exist for dissolved organic carbon (DOC), which is known to be highly bioavailable. This study aims to estimate DOC stocks in coastal permafrost as well as the annual flux into the ocean. DOC concentrations in ground ice were analyzed along the ice-rich Yukon coast (YC) in the western Canadian Arctic. The annual DOC flux was estimated using available numbers for coast length, cliff height, annual erosion rate, and volumetric ice content in different stratigraphic horizons. Our results showed that DOC concentrations in ground ice range between 0.3 and 347.0 mg L^-1 with an estimated stock of 13.6 ± 3.0 g m^-3 along the YC. An annual DOC flux of 54.9 ± 0.9 Mg yr^-1 was computed. These DOC fluxes are low compared to POC and SOC fluxes from coastal erosion or POC and DOC fluxes from Arctic rivers. We conclude that DOC fluxes from permafrost coasts play a secondary role in the Arctic carbon budget. However, this DOC is assumed to be highly bioavailable. We hypothesize that DOC from coastal erosion is important for ecosystems in the Arctic nearshore zones, particularly in summer when river discharge is low, and in areas where rivers are absent

Northern Eurasia Future Initiative (NEFI): facing the challenges and pathways of global change in the 21st century

During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed with regional decision makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include: warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land-use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia's role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large scale water withdrawals, land use and governance change) and potentially restrict or provide new opportunities for future human activities. Therefore, we propose that Integrated Assessment Models are needed as the final stage of global change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts

The twenty-first-century Arctic environment: accelerating change in the atmospheric, oceanic and terrestrial spheres

This is the peer reviewed version of the following article: HODGKINS, R., 2014. The twenty-first century arctic environment: accelerating change in the atmospheric, oceanic and terrestrial spheres. Geographical Journal, 180 (4), pp.429-436, which has been published in final form at: http://dx.doi.org/10.1111/geoj.12112. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.The Arctic possesses distinctive environmental characteristics that act as strong, positive feedbacks on atmospheric warming; in fact, it is almost uniquely susceptible to rapid change brought about through climate warming from both natural and anthropogenic sources. The aim of this commentary is to outline recent and probable future environmental changes in the Arctic. It commences with a consideration of rates of change through the satellite era in air temperatures, sea ice extent, snow cover and the state of balance of the Greenland Ice Sheet. This is subsequently set against fluctuations over previous centuries and millennia. From this observational basis, the commentary moves on to consider factors which particularly amplify rates of change in high northern latitudes, before addressing further feedbacks which may become important, and how Arctic changes may proceed up to the year 2100

The Regulation of Heavy Fuel Oil in Arctic Shipping: Interests, Measures, and Impacts

Since the International Maritime Organization’s (IMO) ban on the use and carriage for use of heavy fuel oil (HFO) for ships operating in Antarctic waters came into effect in 2011, the international community has been engaged in a discourse on whether to adopt a similar standard for ships operating in Arctic waters. The issues are complex as, in addition to reducing the environmental risks posed by HFOs, there are economic and social consequences, including dependence on such fuels by Indigenous peoples. The discourse has involved the IMO, the Arctic Council, industry associations, environmental nongovernmental organizations, and Indigenous peoples. The issue was first raised during the development of the Polar Code and is considered unfinished business of the Code. This chapter discusses the nature of the problem and the challenges to explore a possible regulatory strategy. The chapter will consider the issue in the larger context of the public and private maritime law conventions to consider how an HFO regulatory strategy complements and remains consistent with other elements of maritime regulation