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Data Submission Package for Manuscript 'Moving beyond the physical impervious surface impact and urban habitat fragmentation of Alaska: Quantitative Human Footprint Inference from the first large Scale 30m high-resolution Landscape Metrics Big Data Quantification in R and the Cloud' - MS2With increased globalization, man-made climate change, and urbanization, the landscape – embedded within the Anthropocene - becomes increasingly fragmented. With habitats transitioning and getting lost, globally relevant regions considered ‘pristine', such as Alaska, are no exception. Alaska holds 60% of the U.S. National Park system’s area and is of national and international importance, considering the U.S. is one of the wealthiest nations on earth. These characteristics tie into densities and quantities of human features, e.g., roads, houses, mines, wind parks, agriculture, trails, etc., that can be summarized as ‘impervious surfaces.’ Those are physical impacts and actively affecting urban-driven landscape fragmentation. Using the remote sensing data of the National Land Cover Database (NLCD; https://www.mrlc.gov/data/nlcd-2016-land-cover-alaska ), here we attempt to create the first quantification of this physical human impact on the Alaskan landscape and its fragmentation. We quantified these impacts using the well-established landscape metrics tool ‘Fragstats’, implemented as the R package “landscapemetrics” in the desktop software and through the interface of a Linux Cloud-computing environment. This workflow allows for the first time to overcome the computational limitations of the conventional Fragstats software within a reasonably quick timeframe. Thereby, we are able to analyze a land area as large as approx. 1,517,733 km2 (state of Alaska) while maintaining a high assessment resolution of 30 meters. Based on this traditional methodology, we found that Alaska has a reported physical human impact of c. 0.067%. But when assessed, we additionally overlaid other features that were not included in the input data to highlight the overall true human impact (e.g., roads, trails, airports, governance boundaries in game management and park units, mines, etc.). We found that using remote sensing (human impact layers), Alaska’s human impact is considerably underestimated to a meaningless estimate (0.067%). The state is more seriously fragmented and affected by humans than commonly assumed. Very few areas are truly untouched and display a high patch density with corresponding low mean patch sizes throughout the study area. Instead, the true human impact is likely close to 100% throughout Alaska for several metrics. With these newly created insights, we provide the first state-wide landscape data and inference that are likely of considerable importance for land management entities in the state of Alaska, and for the U.S. National Park systems overall, especially in the changing climate. Likewise, the methodological framework presented here shows an Open Access workflow and can be used as a reference to be reproduced virtually anywhere else on the planet to assess more realistic large-scale landscape metrics. It can also be used to assess human impacts on the landscape for more sustainable landscape stewardship and mitigation in policy.
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Dynamo action in the ionosphere and motions of the magnetospheric plasmaThis thesis presents a study of the dynamic interaction which takes place between the magnetospheric plasma and the underlying neutral atmosphere; it is hoped thus to gain a better understanding of the effects of this interaction upon the steady state configuration of the magnetosphere. The neutral portion of the atmosphere (the neutrosphere) and the overlying ionized regions (the upper atmosphere and magnetosphere) may be regarded as two distinct dynamic domains that interact in a region of transition occurring between 100 and 150 km over the earth. The neutrosphere because of its greater mass will dominate the motion, and the magnetospheric plasma can be expected to undergo motions related to those of the upper neutrosphere and transition region. However, the geomagnetic field restricts the motion of the magnetospheric plasma to a particular class, allowing one to consider the magnetospheric motion to be constrained. Motions in the transition region of the class not permitted the magnetospheric plasma will give rise to forces against the constraint. The reaction of the constraint on the atmosphere of the transition region takes the form of a Lorentz force J x B where J is the current responsible for the well known solar quiet day daily magnetic variation (Sq). The explanation for the production of this current in the transition region has traditionally been presented in terms of a dynamo-like electromotive force generated by motions of the conducting atmosphere through the magnetic field, whence the transition region is aptly named the dynamo region. The Lorentz force represented by this current constitutes a significant term in the equation of motion for the dynamo region. Another important term arises from eddy viscous stresses immediately below the dynamo region. The equation of motion for the dynamo region must thus include such forces as well as the pressure gradient and Coriolis terms. However, our almost total ignorance of the eddy viscous stress field at the lower surface of the dynamo layer at present precludes our deducing the entire dynamo layer winds from the observed Sq magnetic variation. The kinematics of the dynamo layer are discussed and the motion or the dynamo layer is divided into a symmetric and an antisymmetric part. The term symmetric is here used to describe winds in the northern and southern hemisphere that are the mirror images of each other with respect to the equatorial plane. It is demonstrated that the symmetric component gives rise to electrostatic fields transverse to the field lines, but to no currents along the field lines, while the antisymmetric case produces the converse effects. The symmetric and antisymmetric winds are further divided into components according to the horizontal electromotive force they produce. (a) Symmetric Wind. In the case of the symmetric wind, only the portion of the wind producing the solenoidal component of the horizontal dynamo electromotive force is effective in producing ionospheric currents. It is demonstrated that only this current producing wind system acts against the constraints imposed by the geomagnetic field on magnetospheric motions. The motion of the magnetospheric plasma driven by each such wind system is discussed. The earlier treatments of the dynamo theory consider the dynamo region to be a single layer in which the wind system and the electric conductivity are assumed to be uniform in height. A new, more general derivation of the layer's dynamo action is given in which no restrictions are placed upon the vertical distributions. An effective wind is defined which permits the use of the earlier equations relating the current function, the electrostatic field, and the scalar field describing the current producing part of the effective wind. The equation relating the electrostatic field and the current function is essentially that employed by Maeda (1956), allowing his solution for the portion of the electrostatic field associated with the current producing wind to remain unaffected by the stratification of the wind system. Mathematical techniques for solving the dynamo equations for the electrostatic field are developed. These allow for a quite general conductivity distribution over the globe, only requiring that it be expressible in surface harmonics. The effect of undetected zonal currents upon the solution for the electrostatic field is discussed. It is suggested that a considerable diurnal component of electrostatic field and other components as well may be hidden from us by our inability to detect the prevailing magnetic perturbations produced by zonal currents. The electrostatic field associated with the non-current producing components of the symmetric wind is likewise hidden from us. (b) Antisymmetric Wind. The equations for the current driven by the antisymmetric component of wind are derived, and some of the effects of such currents are discussed. It is found that the conduction of current along the field lines from one hemisphere to the other is associated with an interhemispheric stress between geomagnetically conjugate points of order 3 x 10⁻⁷ newtons/meter². In addition it is found that an antisymmetric layer current density of 5 amperes/km into the polar cap region (across the 75° latitude circle) might give rise to a displacement of about 150 km in the relative position of the conjugate points defined by field lines of the magnetospheric tail. It is suggested that the dynamo action in the 100 to 150 km height plays a role in determining the manner in which the magnetosphere divides itself into the corotating region and the magnetospheric tail.
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Gulf of Alaska Limitations ReportExecutive Summary The purpose of this report is to document economic and demographic changes for communities of the Gulf of Alaska, Southcentral Alaska, and Southeast Alaska over the period of 1950 to 2023. Over this period several major changes were made to the way that State and Federal commercial fisheries were managed in Alaska waters. These changes -particularly the introduction of the Limited Entry program in the mid-1970s and individual fishing quotas in the mid-1990’s - limited access to fisheries. Changes to fisheries access has implications not just for the fisherman directly included or excluded, but also more broadly to their home communities through the economic spillover effects that the fishing industry creates. Watson et al., (2021) shows that the impacts of the commercial fishing industry in Alaska extends beyond the income it provides to vessel captains. Fishing activity also provides for crew member and shore-side processing jobs and spillover effects into upstream and downstream industries. It also creates broader induced economic effects as income and wages are spent on local goods and services. However, as Watson et al., (2021) shows, these effects only tend to materialize in the home communities of fishermen. In other words, economic impacts follow fishermen.
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Effects on Households of a Proposed Anchorage Municipal Sales TaxExecutive Summary A coalition of Anchorage business leaders has proposed a sales tax for the Municipality of Anchorage. The tax would be levied at 3% of taxable expenditures. The proposal would allocate 2/3 of the revenues from the tax (2% of taxable expenditures) allocated to property tax relief, and the remaining one third (one percent of taxable expenditures) set aside to fund a capital improvements program. The tax would be temporary, set to expire after about 8 years. A study led by Nolan Klouda at the University of Alaska Anchorage Center for Economic Development (CED) estimated that the proposed sales tax would generate $180 million annually, with 16% of the total paid by non-Anchorage residents. A subsequent update sponsored by Project Anchorage initiative proponents also estimated that the tax would collect $180 million in total but projected 21% would be contributed by non-residents. The current study revisited the assumptions and data used by the previous reports, and after making minor accounting adjustments, confirmed the total revenue estimate of about $180 million, but with 20.5% ($37 million) derived from non-residents. It took a closer look at the $143 million estimated to be collected from residents and the property tax offsets these households might expect, focusing on the distribution of impacts across Anchorage households with different incomes.
