The problem of tsunami run-up has been extensively studied in the framework of the shallow water equations. Typically one assumes that the initial water displacement and the initial velocity are known, and then the run-up is computed using the Carrier-Greenspan transformation. The inverse problem consists of recovering the initial displacement and/or velocity from the shoreline oscillations. It has been previously demonstrated that the initial displacement can be recovered from shoreline oscillations under the assumption of zero initial velocity for the sloping plane beach. We show that this result can be generalised to arbitrary power-shaped bathymetries. Moreover, we show that for non-breaking waves, the contributions of velocity and displacement can be separated at the shoreline. This separation allows for the recovery of both the initial displacement and velocity from the shoreline oscillations.

This work addresses itself to the role that ethno-historical research can play in understanding the present day life of Indians and Eskimos living in a multi-ethnic community in the interior of Alaska. To do this, an attempt has been made to write and analyze the history of the community in a manner that reflects the separate tribal, ethnic, and individual differences of the various people who settled there. Documentation of cultural patterning by different groups enables the researcher to understand the dynamics of cultural persistence and change throughout time in land use, social relations, economic pursuits, attitudes and values. This research does not presuppose that individuals and groups who are influenced by outside intrusions will necessarily respond by changing their ways of life. Instead, the problem has been to investigate the nature of the outside influences and the manner in which these intrusions are perceived by members of the community and the nature of the responses made to them. Written documentation is employed to set an order to the events, but my main reliance is on personal recollections of past events to discern the feelings and associations that people today hold for those forces that have affected their lives in the past and that are now operating

Since WWII Alaska not only has been a major player in the defensive strategy of the United States, but it also has been considered an important military testing ground. This paper will advance the thesis that military operations are often detrimental and, indeed, hazardous to the resident population. Specifically, the SM-1A, a nuclear reactor the Army built at Fort Greely, Alaska in 1962, will be examined with emphasis on the fact that it was used to test nuclear energy production. Additionally, because of the discharge of low level radioactive waste into Jarvis Creek, which runs through Delta, there may be an abnormally high incidence of cancer within the nearby community. Furthermore, this is not an isolated case and other examples of nuclear tests will be presented as evidence.

This series of technical quarterly reports from the Alaska Earthquake Center (AEC) includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, fieldwork, our online presence, and lists publications and presentations by AEC staff. Multiple AEC staff members contribute to this report. It is issued within 1-2 months after the completion of each quarter Q1: January-March, Q2: April-June, Q3: July-September, and Q4: October-December. The first report was published for January-March, 2021.

This 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.

Executive 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.

Jet contrails can be frequently observed in the subarctic setting of Fairbanks, Alaska, much like in the contiguous United States. Since March of 2000, continuous digital imagery of the sky was obtained, supported by FAA flight data and radiosonde ascents at the Fairbanks International Airport. There were a total of 2504 over-flights (March 2000-July 2002) at Fairbanks, but for a great number of these, contrail observations were not possible due to clouds and/or darkness. For 590 cases, the formation of contrails could be confirmed; their life span varied widely from a few seconds to several hours. In general, cold temperatures and high relative humidity at flight level favored the formation of contrails. These conditions are frequently found in the upper troposphere close to the tropopause. Using our substantial database, different existing algorithms were tested and, in part, improved in order to predict contrail formation and lifetime. The best results were obtained with an algorithm described by Schumann (1996) and an aircraft specific contrail factor of 0.036 g/kgK. For contrails within 4 hours of the radiosonde ascents, a combined hit rate for correctly forecasting the occurrence and non-occurrence of contrails of 92% was obtained.