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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

A Case Study Using 2019 Pre-Monsoon Snow And Stream Chemistry In The Khumbu Region, Nepal, Heather M. Clifford, Mariusz Potocki, Inka Koch, Tenzing Sherpa, Mike Handley, Elena Korotkikh, Douglas Introne, Susan Kaspari, Kimberley Miner, Tom Matthews, Baker Perry, Heather Guy, Ananta Gajurel, Praveen Kumar Singh, Sandra Elvin, Aurora C. Elmore, Alex Tait, Paul A. Mayewski Oct 2021

A Case Study Using 2019 Pre-Monsoon Snow And Stream Chemistry In The Khumbu Region, Nepal, Heather M. Clifford, Mariusz Potocki, Inka Koch, Tenzing Sherpa, Mike Handley, Elena Korotkikh, Douglas Introne, Susan Kaspari, Kimberley Miner, Tom Matthews, Baker Perry, Heather Guy, Ananta Gajurel, Praveen Kumar Singh, Sandra Elvin, Aurora C. Elmore, Alex Tait, Paul A. Mayewski

Geological Sciences Faculty Scholarship

This case study provides a framework for future monitoring and evidence for human source pollution in the Khumbu region, Nepal. We analyzed the chemical composition (major ions, major/trace elements, black carbon, and stable water isotopes) of pre-monsoon stream water (4300–5250 m) and snow (5200–6665 m) samples collected from Mt. Everest, Mt. Lobuche, and the Imja Valley during the 2019 pre-monsoon season, in addition to a shallow ice core recovered from the Khumbu Glacier (5300 m). In agreement with previous work, pre-monsoon aerosol deposition is dominated by dust originating from western sources and less frequently by transport from southerly air mass …


Diatoms Of The Intertidal Environments Of Willapa Bay, Washington, Usa As A Sea-Level Indicator, Isabel Hong, Benjamin P. Horton, Andrea D. Hawkes, Robert J. O.Donnell Iii, Jason S. Padgett, Tina Dura, Simon E. Engelhart Aug 2021

Diatoms Of The Intertidal Environments Of Willapa Bay, Washington, Usa As A Sea-Level Indicator, Isabel Hong, Benjamin P. Horton, Andrea D. Hawkes, Robert J. O.Donnell Iii, Jason S. Padgett, Tina Dura, Simon E. Engelhart

Geological Sciences Faculty Scholarship

An understanding of the modern relationship between diatom species and elevation is a prerequisite for using fossil diatoms to reconstruct relative sea level (RSL). We described modern diatom distributions from seven transects covering unvegetated subtidal environments to forested uplands from four tidal wetland sites (Smith Creek, Bone River, Niawiakum River, and Naselle River) of Willapa Bay, Washington, USA. We compared our diatom dataset (320 species from 104 samples) to a series of environmental variables (elevation, grain-size, total organic carbon (TOCSOM), and porewater salinity) using hierarchical clustering and ordination. While no single variable consistently explains variations in diatom assemblages …


Dynamic Microclimate Boundaries Across A Sharp Tropical Rainforest–Clearing Edge, Eric A. Graham, Mark Hansen, William J. Kaiser, Yeung Lam, Eric Yuen, Philip W. Rundel Apr 2021

Dynamic Microclimate Boundaries Across A Sharp Tropical Rainforest–Clearing Edge, Eric A. Graham, Mark Hansen, William J. Kaiser, Yeung Lam, Eric Yuen, Philip W. Rundel

Biology Faculty Scholarship

As landscapes become increasingly fragmented, research into impacts from disturbance and how edges affect vegetation and community structure has become more important. Descriptive studies on how microclimate changes across sharp transition zones have long existed in the literature and recently more attention has been focused on understanding the dynamic patterns of microclimate associated with forest edges. Increasing concern about forest fragmentation has led to new technologies for modeling forest microclimates. However, forest boundaries pose important challenges to not only microclimate modeling but also sampling regimes in order to capture the diurnal and seasonal dynamic aspects of microclimate along forest edges. …


Drought-Induced Biomass Burning As A Source Of Black Carbon To The Central Himalaya Since 1781 Ce As Reconstructed From The Dasuopu Ice Core, Joel D. Barker, Susan Kaspari, Paulo Gabrielli, Anna Wegner, Emilie Beaudon, M. Roxana Sierra-Hernández, Lonnie Thompson Apr 2021

Drought-Induced Biomass Burning As A Source Of Black Carbon To The Central Himalaya Since 1781 Ce As Reconstructed From The Dasuopu Ice Core, Joel D. Barker, Susan Kaspari, Paulo Gabrielli, Anna Wegner, Emilie Beaudon, M. Roxana Sierra-Hernández, Lonnie Thompson

Geological Sciences Faculty Scholarship

Himalayan glaciers are melting due to atmospheric warming, with the potential to limit access to water for more than 25 % of the global population that resides in these glacier meltwater catchments. Black carbon has been implicated as a factor that is contributing to Himalayan glacier melt, but its sources and mechanisms of delivery to the Himalayas remain controversial. Here, we provide a 211-year ice core record spanning 1781–1992 CE for refractory black carbon (rBC) deposition from the Dasuopu glacier ice core that has to date provided the highest-elevation ice core record (7200 m). We report an average rBC concentration …


Carbonaceous Matter In The Atmosphere And Glaciers Of The Himalayas And The Tibetan Plateau: An Investigative Review, Chaoliu Li, Fangping Yan, Shichang Kang, Caiqing Yan, Zhaofu Hu, Pengfei Chen, Shaopeng Gao, Chao Zhang, Cenlin He, Susan Kaspari, Aron Stubbins Jan 2021

Carbonaceous Matter In The Atmosphere And Glaciers Of The Himalayas And The Tibetan Plateau: An Investigative Review, Chaoliu Li, Fangping Yan, Shichang Kang, Caiqing Yan, Zhaofu Hu, Pengfei Chen, Shaopeng Gao, Chao Zhang, Cenlin He, Susan Kaspari, Aron Stubbins

Geological Sciences Faculty Scholarship

Carbonaceous matter, including organic carbon (OC) and black carbon (BC), is an important climate forcing agent and contributes to glacier retreat in the Himalayas and the Tibetan Plateau (HTP). The HTP – the so-called “Third Pole” – contains the most extensive glacial area outside of the polar regions. Considerable research on carbonaceous matter in the HTP has been conducted, although this research has been challenging due to the complex terrain and strong spatiotemporal heterogeneity of carbonaceous matter in the HTP. A comprehensive investigation of published atmospheric and snow data for HTP carbonaceous matter concentration, deposition and light absorption is presented, …


Development Of Environmental Metabarcoding Analysis For Use In Ecological Studies Of Aquatic Fungal And Oomycete Communities Using Nanopore Sequencing, Douglas Bennett Jan 2021

Development Of Environmental Metabarcoding Analysis For Use In Ecological Studies Of Aquatic Fungal And Oomycete Communities Using Nanopore Sequencing, Douglas Bennett

All Master's Theses

One of several factors contributing to amphibian decline are organisms called water molds (oomycetes), which parasitize and kill amphibian and fish eggs, larvae, and occasionally adults. Amphibian decline is one of the most difficult issues facing ecologists and conservationists to date; half of amphibian species are in severe decline and one third of amphibian species are facing extinction, threatening the stability of ecosystems globally. Multiple oomycete species are known to cause the disease saprolegniasis and contribute to amphibian decline; however, the full range of species involved is not presently known. This study evaluated the Oxford Nanopore minION DNA sequencer (R9.2 …