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Anna I. Hamilton

Publications and source records attributed to Anna I. Hamilton.

2 recordsLinked to original sources

Assessment of barrier island morphological change in northern Alaska

Arctic barriers islands are highly dynamic features influenced by a variety of oceanographic, geologic, and environmental factors. Many Alaskan barrier islands and spits serve as habitat and protection for native species, as well as shelter the coast from waves and storms that cause flooding and degradation of coastal villages. This study summarizes changes to barrier morphology in time and space along the North Slope coast of Alaska between the United States-Canadian border and Cape Beaufort from 1947 to 2020. Changes considered in this study include number of barriers, area and perimeter, shoreline length, barrier sinuosity and width, presence and number of relict terminus features, presence and coverage of tundra vegetation, barrier orientation, and elevation metrics. Wave conditions are also summarized and related to changes in barrier morphology. The results in this report help to better predict future barrier evolution and prevalence along Alaska’s coast by increasing our understanding of Arctic barrier development, migration and degradation.

Alaska

Best practices for continuous monitoring of temperature and flow in wadeable streams

The United States Environmental Protection Agency (U.S. EPA) is working with its regional offices, states, tribes, river basin commissions and other entities to establish Regional Monitoring Networks (RMNs) for freshwater wadeable streams. To the extent possible, uninterrupted, biological, temperature and hydrologic data will be collected on an ongoing basis at RMN sites, which are primarily located on smaller, minimally disturbed forested streams. The primary purpose of this document is to provide guidance on how to collect accurate, year-round temperature and hydrologic data at ungaged wadeable stream sites. It addresses questions related to equipment needs, sensor configuration, sensor placement, installation techniques, data retrieval, and data processing. This guidance is intended to increase comparability of continuous temperature and hydrologic data collection at RMN sites and to ensure that the data are of sufficient quality to be used in future analyses. It also addresses challenges posed by year-round deployments. These data will be used for detecting temporal trends; providing information that will allow for a better understanding of relationships between biological, thermal, and hydrologic data; predicting and analyzing climate change impacts and quantifying natural variability.

Report