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"Stephenson, Scott"
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New Trans-Arctic shipping routes navigable by midcentury
Recent historic observed lows in Arctic sea ice extent, together with climate model projections of additional ice reductions in the future, have fueled speculations of potential new trans-Arctic shipping routes linking the Atlantic and Pacific Oceans. However, numerical studies of how projected geophysical changes in sea ice will realistically impact ship navigation are lacking. To address this deficiency, we analyze seven climate model projections of sea ice properties, assuming two different climate change scenarios [representative concentration pathways (RCPs) 4.5 and 8.5] and two vessel classes, to assess future changes in peak season (September) Arctic shipping potential. By midcentury, changing sea ice conditions enable expanded September navigability for common open-water ships crossing the Arctic along the Northern Sea Route over the Russian Federation, robust new routes for moderately ice-strengthened (Polar Class 6) ships over the North Pole, and new routes through the Northwest Passage for both vessel classes. Although numerous other nonclimatic factors also limit Arctic shipping potential, these findings have important economic, strategic, environmental, and governance implications for the region.
Journal Article
Projected 21st-century changes to Arctic marine access
Climate models project continued Arctic sea ice reductions with nearly ice-free summer conditions by the mid-21st century. However, how such reductions will realistically enable marine access is not well understood, especially considering a range of climatic scenarios and ship types. We present 21st century projections of technical shipping accessibility for circumpolar and national scales, the international high seas, and three potential navigation routes. Projections of marine access are based on monthly and daily CCSM4 sea ice concentration and thickness simulations for 2011–2030, 2046–2065, and 2080–2099 under 4.5, 6.0, and 8.5 W/m
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radiative forcing scenarios. Results suggest substantial areas of the Arctic will become newly accessible to Polar Class 3, Polar Class 6, and open-water vessels, rising from ~54 %, 36 %, and 23 %, respectively of the circumpolar International Maritime Organization Guidelines Boundary area in the late 20th century to ~95 %, 78 %, and 49 %, respectively by the late 21st century. Of the five Arctic Ocean coastal states, Russia experiences the greatest percentage access increases to its exclusive economic zone, followed by Greenland/Denmark, Norway, Canada and the U.S. Along the Northern Sea Route, July-October navigation season length averages ~120, 113, and 103 days for PC3, PC6, and OW vessels, respectively by late-century, with shorter seasons but substantial increases along the Northwest Passage and Trans-Polar Route. While Arctic navigation depends on other factors besides sea ice including economics, infrastructure, bathymetry, and weather, these projections are useful for strategic planning by governments, regulatory agencies, and the global maritime industry to assess spatial and temporal ranges of potential Arctic marine operations in the coming decades.
Journal Article
Orion by Walt Simonson
\"Walt Simonson's stunning, unmistakable art and storytelling are on full display here in his groundbreaking work ORION. Expanding the beloved universe originally created by Jack Kirby, Simonson's sprawling storylines and dynamic artwork elevate his titular hero, as well as the rest of the Fourth World's indispensible characters, to incredible new heights. Collected here for the first time are all twenty-five issues of Walter Simonson's ORION, as well as never-before reprinted short stories, pinups and sketch material.\"-- Provided by publisher.
BOOK
The challenge for courts in a moderately rigid constitution
While the challenges with highly flexible and highly rigid constitutions are well-known, comparatively little is understood about the challenges that may arise with moderately rigid constitutions. This article argues that moderately rigid constitutions increase the challenge for courts in two related respects. First, it places them between competing normative and practical demands. A moderately rigid constitution weakens the normative case for the judiciary to develop the constitution to, for example, expand protection for rights and freedoms, yet places considerable practical demands on courts to undertake such developments. Second, a moderately rigid constitution introduces an additional point of uncertainty into the law because its degree of rigidity is capable of supporting diametrically opposed conclusions depending on whether formal amendment is interpreted as being largely available or largely unavailable. The article illustrates this challenge by reference to Australia's experience with a moderately rigid constitution.
Journal Article
Leveraging the past to prepare for the future of Air Force intelligence analysis
\"This report describes steps the U.S. Air Force can take to help ensure that it has the capability needed to provide intelligence analysis support to a broad range of service and combatant commander needs, including support to ongoing irregular warfare operations, and to conventional warfare with a near-peer competitor. It describes lessons from past operations that have direct implications for Air Force intelligence analysis or that Air Force intelligence analysis could help to address. It also describes future challenges for Air Force intelligence analysis. It makes recommendations related to doctrine, training and career field development, analysis tools, and processes that can help to address the lessons from the past and prepare Air Force intelligence analysts for the challenges of the future\"--Publisher's description.
Book
The impact of black carbon emissions from projected Arctic shipping on regional ice transport
The direct and indirect effects of global emissions of black carbon (BC) on the evolution of Arctic climate has been well documented. The significance of within-Arctic emissions of BC is less certain. In light of this, an ensemble of scenarios are developed that simulate the hypothetical diversion of 75% of current and projected shipping traffic from the Suez Canal to the Northern Sea Route (NSR). This experiment shows that BC from ships results in a small change in climate forcing that does not influence the Arctic-wide trajectory of change. However, the shift in forcing from the Suez route to the NSR not only influences regional evolution of sea ice cover, but also results in regional feedbacks that in some locations amplify (e.g. Greenland Sea) and in other locations damp (e.g. Labrador Sea) the sea ice retreat under anthropogenic climate change. The primary mechanism underlying these regional effects is a shift in circulation rather than direct thermodynamic forcing. The most significant impacts are distal from the emissions sources, which is likely to have policy implications as the expansion of industrial and transportation activities into the Arctic is considered.
Journal Article
Divergent long-term trajectories of human access to the Arctic
Subzero temperatures at high latitudes typically restrict shipping but facilitate ground transportation. A study quantifies the impacts of climate change on Arctic transportation by mid-century and finds that all eight Arctic states will probably suffer steep declines in inland transport, but will reap the benefits of faster sea travel.
Understanding climate change impacts on transportation systemsis particularly critical in northern latitudes, where subzero temperatures restrict shipping, but enable passage of ground vehicles over frozen soil and water surfaces. Although the major transport challenges related to climate warming are understood, so far there have been no quantitative projections of Arctic transport system change. Here we present a new modelling framework to quantify changing access to oceans and landscapes northward of 40° N by mid-century. The analysis integrates climate and sea-ice model scenarios
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with topography, hydrography, land cover, transportation infrastructure and human settlements. Declining sea-ice concentration and thickness suggest faster travel and improved access to existing (+5 to +28%) and theoretical (+11 to +37%) offshore exclusive economic zones of Canada, Greenland, Russia and the US. The Northern Sea Route, Arctic Bridge and North Pole routes are projected to become fully accessible from July–September, averaging ∼11, 15 and 16 days to traverse, respectively, whereas the Northwest Passage will not. All eight Arctic states are projected to suffer steep declines (−11 to −82%) in accessibility inland, driven by lost potential for winter road construction caused by milder winters and deeper snow accumulation.
Journal Article
Arctic shipping guidance from the CMIP6 ensemble on operational and infrastructural timescales
The expectation of a seasonally ice-free Arctic by mid-century has sparked economic and geopolitical interest in potential Arctic opportunities and risks. But substantial sea ice variability across timescales suggests an uncertain future for forecasts of marine accessibility, especially over operational (< 2 years) and infrastructural (> 5 years) time spans that significantly influence decision-makers planning ship routing, emergency management, port investment, and more. Here, we use three marine accessibility schemes applied to CMIP6 scenarios to quantify Arctic shipping season variability and uncertainty across these decision-relevant timescales. We compare route projections across climate models and accessibility schemes to show that the choice of methodology significantly affects information important for decision-making. We find high variability and uncertainty in voyage time notably in the critical “shoulder” seasons on both timescales. This leads to increased risk over the next several decades, with high short-term uncertainty particularly at the end of the shipping season for the next 25 years. Navigation risk is expected to decline from 2045 onward. Knowledge that accounts for sea ice variability, simulation quality, and accessibility algorithm allows for better investment decisions and the minimization of unforeseen costs due to delayed and canceled voyages. Here we develop and demonstrate a framework for developing more timely and salient information to guide decisions on Arctic shipping relevant to both operational and infrastructural horizons as climate projections become spatially and physically better resolved.
Journal Article