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Palynomorphs are one of the few groups of fossils that provide biostratigraphic control in marine to nonmarine rocks and can be applied as proxies for paleoenvironmental and paleoclimatic interpretations. Their utility is enhanced by their microscopic size, which is usually less than 200 micrometres; they are thus easily recovered from small rock samples. They occur throughout the Phanerozoic and are therefore invaluable in refining biostratigraphic control of Arctic successions in Alaska, Arctic Canada, Greenland, northern Europe, and northern Russia. The objective of the Circum-Arctic Palynological Event (CAPE) Stratigraphy series of papers is to integrate data published on Arctic palynomorphs to delineate palynological events (palynoevents) across the Arctic for the Silurian to Cenozoic. Once the series of papers is complete, the data will also be used to compile a TimeScale Creator datapack that can be updated and calibrated on an ongoing basis. Palynoevents include taxon originations (first occurrences or FOs) and extinctions (last occurrences, or LOs) and some abundance events. The palynoevents are correlated with established chronostratigraphic horizons such as bases of ammonoid zones or stages, and hence their chronostratigraphy is independent of the absolute time scale in millions of years. In addition to the palynostratigraphic papers, the series includes a paper detailing the paleogeography of the circum-Arctic regions, including informative maps, as well as a paper providing a palynological perspective of the Cenozoic shift from greenhouse to icehouse conditions. [ABSTRACT FROM AUTHOR]

Since 2015, the Innovative Technology for Arctic Exploration (ITAE) program has supported maritime technology development that contributes to economic growth, ocean health, and ocean management in Alaska. The program does this in multiple ways: through public-private partnerships, platform and small-scale sensor design, and research to operations, commercialization, and application of science-driven technologies. ITAE is a high-risk, high-reward research collaborative that provides support and expertise for creative scientists pursuing highly innovative research solutions with the potential for broad impact in US Arctic marine sciences. This program is funded through NOAA to support projects that may be overlooked in the traditional peer-review process because of their inherent risk. However, not all risks lead to success, not every risk leads to failure, and not all failures eliminate success. Development and growth are nurtured by risk and temporary setbacks. The science advanced by these researchers and collaborators forges new paths of discovery. While the Arctic is an excellent testbed, in part, due to its extreme conditions, the technologies and lessons detailed here are transferable to oceanographic research outside of the Arctic. This paper reviews the ITAE program as well as the successes and failures of this dedicated Arctic innovation collaborative at the NOAA Pacific Marine Environmental Laboratory. [ABSTRACT FROM AUTHOR]

Food cellars, otherwise referred to as ice or meat cellars, (lednik in Russian, k'aetyran in Chukchi, sigluaq in Iñupiaq, and siqlugaq in Yupik) are a natural form of refrigeration in permafrost or seasonally frozen ground used to preserve, age, and ferment foods harvested for subsistence, including marine mammals, birds, fish, and plants. Indigenous peoples throughout the Arctic have constructed cellars in frozen ground for millennia. This paper focuses on cellars in Russian and American coastal and island communities of the Bering Strait, the region otherwise known as Beringia. This area has a unique, culturally rich, and politically dynamic history. Many traditions associated with cellars are threatened in Chukchi communities in Russia because of the impacts of climate change, relocation, dietary changes, and industrial development. However, even with warmer temperatures, cellars still provide a means to age and ferment food stuffs following traditional methods. In cooperation with local stakeholders, we measured internal temperatures of 18 cellars in 13 communities throughout the Bering Strait region and northern Alaska. Though cellars are widely used in permafrost regions, their structure, usage, and maintenance methods differ and exhibit influences of local climates, traditions, and economic activities. Monitoring internal temperatures and recording structural descriptions of cellars is important in the face of climate change to better understand the variety and resilience of living adaptations in different cold regions. [ABSTRACT FROM AUTHOR]

Accurate knowledge of the reflectance from snow/ice covered surface is of fundamental importance for the investigation and retrieval of snow parameters and atmospheric constituents. This is a prerequisite for identifying and quantifying changes in the environment and climate in Polar Regions. However, the current differences between simulated and measured reflectance in a coupled snow-atmosphere system, leads to systematic errors in the determination of the amount of trace gases, aerosol and cloud parameters from space based and airborne passive remote sensing observations. In this paper, we describe studies of the retrieval of snow grain morphologies, also called habits, and their use to determine reflectance and test the accuracy of our radiative transfer model simulations of reflectance by comparison with measurements. Firstly we report on a sensitivity study. This addresses the requirement for adequate a priori knowledge about snow models and ancillary information about the atmosphere; the objective being to minimize differences between measurements and simulation. For this aim we use the well-validated phenomenological radiative transfer model SCIATRAN. Secondly and more importantly, we present a novel two-stage snow grain morphology (i.e. size and shape of ice crystals in the snow) retrieval algorithm. We then describe the use of this new retrieval to estimate the most representative snow model, using different types of snow morphologies, for the airborne observation conditions, performed by NASA's Cloud Absorption Radiometer (CAR). The results show that the retrieved ice crystal shapes are consistent with the expected snow morphology (estimated from temperature information) in the measurement area over Barrow/Utqiagvik, Alaska in 2008. Thirdly, we present a comprehensive comparison of the simulated reflectance (using retrieved snow grain size and shape as well as independent atmospheric data) with that from airborne CAR measurements in the visible and NIR wavelength range. The results of this comparison are used to assess the quality and accuracy of the radiative transfer model in the simulation of the reflectance in a coupled snow-atmosphere system. Assuming that that snow layer consists of ice crystals with aggregates of 8 column ice habit having an effective radius ~ 98.83 µm, we find that for a surface covered by old snow, the Pearson correlation coefficient, R, between measurements and simulations to be 0.98 (R² ~ 0.96). For freshly fallen snow on areas having surface inhomogenity, the correlation is ~ 0.97 (R² ~ 0.94) in the infrared and 0.88 (R² ~ 0.77) in the visible wavelengths assuming that snow layer consists of aggregate of 5 plate ice habit with effective radius ~ 83.41 µm. Largest differences between simulated and measured values are observed in glint, i.e. in the angular regions of specular and near-specular reflection, with relative azimuth angles < ± 40° in forward scattering direction. The absolute difference between the modeled results and measurements in off-glint regions with viewing zenith angle less than 50° is generally small ~ ± 0.025 and does not exceed ± 0.05. These results will help to improve snow surface reflectance in the snow- atmosphere system algorithms designed to retrieve atmospheric parameters such as aerosol optical thickness in the Polar Regions. [ABSTRACT FROM AUTHOR]

In 1992 an abandoned federal radioactive waste dump was discovered in Arctic Alaska. The discovery of this site, a byproduct of the Atomic Energy Commission program known as Project Chariot, sent shockwaves throughout Iñupiaq communities and ignited a heated controversy over the health effects of subsisting on a "tundra of sickness." Drawing on thirty months of ethnographic research in Arctic Alaska, this paper explores a host of environmental, social, and moral uncertainties sparked by toxic waste. Anthropological claims regarding the extent to which "traditional ecological knowledge" will empower local communities and foster self-determination are challenged. Ultimately the paper argues that TEK has been conceived in such restrictive terms that it misrepresents the dynamic, emerging, and at times contradictory responses to toxic waste in the Arctic today. Moreover, there is dire need for a more materialist, as opposed to discourse-based, approach that acknowledges the very real threat of toxic waste to physical, and therefore, cultural reproduction. [ABSTRACT FROM AUTHOR]

Tundra sodding, a new technique available to rehabilitate disturbed wetlands in the Arctic, is based on Iñupiaq traditional knowledge. C. Hopson, an Iñupiaq elder from Barrow and author of this paper, guided the development and field application of this new technique by providing traditional knowledge he learned as a youth from his elders. Tundra sodding has several advantages over other land rehabilitation techniques, the most important being that it can establish a mature plant community of indigenous species in a single growing season. In all sampling years, the plant communities at sodded sites were dominated by two rhizomatous graminoids, Eriophorum angustifolium and Carex aquatilis. These sedges also were dominant in all years in reference tundra. Also common to the plant communities in both reference tundra and sodded sites were 18 other vascular species (grasses, evergreen and deciduous shrubs, and forbs). Results from two to five growing seasons indicate that tundra sod can reduce the overall subsidence due to thawing of shallow permafrost. We harvested sod on three occasions from an area slated for gravel mining. In the summers of 2007 and 2008, we transplanted 334 m2 of tundra sod to portions of three sites to test the feasibility of the method. In summer 2010, we used the experience gained from that work to rehabilitate an entire site (1114 m2). This tundra sodding technique is labor intensive and costly compared to other rehabilitation techniques, but it offers advantages that justify its use when rapid rehabilitation of a disturbed site is needed. [ABSTRACT FROM AUTHOR]

Two ideas have helped inform anthropological interpretations of Subarctic prehistory. One imagines the Subarctic as geographically removed from centers of social change and humanwilled history. The other envisions the subarctic environment as excessively constraining and austere. Both ideas have been used to construct a prehistory that emerges as ahistorical, acultural, and devoid of social actors. This paper charts the logic of these explanations and their implications for an archaeological understanding of the Subarctic past, while offering archaeological and ethnographic evidence that counters these interpretations. Subarctic archaeology should pay greater attention to deciphering the historical, social, and cultural realms within which subarctic huntergatherers lived. [ABSTRACT FROM AUTHOR]

This paper presents the first systematic comparison between south-facing monofacial and bifacial photovoltaic (PV) modules, as well as between south-facing bifacial and vertical east-west facing bifacial PV modules in Alaska. The state's solar industry, driven by the high price of energy and dropping equipment costs, is quickly growing. The challenges posed by extreme sun angles in Alaska's northern regions also present opportunities for unique system designs. Annual bifacial gains of 21% were observed between side by side south-facing monofacial and bifacial modules. Vertical east-west bifacial modules had virtually the same annual production as south-facing latitude tilt bifacial modules, but with different energy production profiles. [ABSTRACT FROM AUTHOR]

An ecological study is presently being carried out at the headwaters of Imnavait Creek to develop a better understanding of the dynamics of an arctic ecosystem. While all ecosystems are driven by both energy and mass inputs, in an arctic setting this is much more evident. Therefore it is critical that we have a detailed understanding of the hydrology of the basin. In the United States, no hydrological studies of an arctic watershed have been made where measurements are continued throughout the winter season. While most biological processes are dormant throughout the winter, this is not true of physical processes such as active layer freezing and thawing and snow accumulation and redistribution by wind. This paper summarizes what we have learned hydrologically from three years of study al an arctic watershed, Imnavait Creek. [ABSTRACT FROM AUTHOR]

Changes in vegetation distribution, structure, and function can modify the canopy properties of terrestrial ecosystems, with potential consequences for regional and global climate feedbacks. In the Arctic, climate is warming twice as fast as compared to the global average (known as 'Arctic amplification'), likely having stronger impacts on arctic tundra vegetation. In order to quantify these changes and assess their impacts on ecosystem structure and function, methods are needed to accurately characterize the canopy properties of tundra vegetation types. However, commonly used ground-based measurements are limited in spatial and temporal coverage, and differentiating low-lying tundra plant species is challenging with coarse-resolution satellite remote sensing. The collection and processing of multi-sensor data from unoccupied aerial systems (UASs) has the potential to fill the gap between ground-based and satellite observations. To address the critical need for such data in the Arctic, we developed a cost-effective multi-sensor UAS (the 'Osprey') using off-the-shelf instrumentation. The Osprey simultaneously produces high-resolution optical, thermal, and structural images, as well as collecting point-based hyperspectral measurements, over vegetation canopies. In this paper, we describe the setup and deployment of the Osprey system in the Arctic to a tundra study site located in the Seward Peninsula, Alaska. We present a case study demonstrating the processing and application of Osprey data products for characterizing the key biophysical properties of tundra vegetation canopies. In this study, plant functional types (PFTs) representative of arctic tundra ecosystems were mapped with an overall accuracy of 87.4%. The Osprey image products identified significant differences in canopy-scale greenness, canopy height, and surface temperature among PFTs, with deciduous low to tall shrubs having the lowest canopy temperatures while non-vascular lichens had the warmest. The analysis of our hyperspectral data showed that variation in the fractional cover of deciduous low to tall shrubs was effectively characterized by Osprey reflectance measurements across the range of visible to near-infrared wavelengths. Therefore, the development and deployment of the Osprey UAS, as a state-of-the-art methodology, has the potential to be widely used for characterizing tundra vegetation composition and canopy properties to improve our understanding of ecosystem dynamics in the Arctic, and to address scale issues between ground-based and airborne/satellite observations. [ABSTRACT FROM AUTHOR]