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Full-Text Articles in Atmospheric Sciences

Beef Cow Operations During Drought: Dealing With More Than Dry Conditions, Matthew Stockton Aug 2021

Beef Cow Operations During Drought: Dealing With More Than Dry Conditions, Matthew Stockton

Cornhusker Economics

The most recent drought conditions have grown to cover a large portion of the west and the central United States, as shown in Figure 1. Those depending on rain continue to watch and hope that conditions will change, while implementing and considering various strategies to preserve their livelihoods. Those who have been in the business for years have seen other occasions when dry conditions limited forage production and created hardship. Each occurrence has varying outcomes, depending on the many factors faced by individuals. While drought may produce the same dry conditions for many, its effects are individualized. There are as …


Multi-Modal Data Fusion, Image Segmentation, And Object Identification Using Unsupervised Machine Learning: Conception, Validation, Applications, And A Basis For Multi-Modal Object Detection And Tracking, Nicholas Lahaye Aug 2021

Multi-Modal Data Fusion, Image Segmentation, And Object Identification Using Unsupervised Machine Learning: Conception, Validation, Applications, And A Basis For Multi-Modal Object Detection And Tracking, Nicholas Lahaye

Computational and Data Sciences (PhD) Dissertations

Remote sensing and instrumentation is constantly improving and increasing in capability. Included within this, is the increase in amount of different instrument types, with various combinations of spatial and spectral resolutions, pointing angles, and various other instrument-specific qualities. While the increase in instruments, and therefore datasets, is a boon for those aiming to study the complexities of the various Earth systems, it can also present a large number of new challenges. With this information in mind, our group has set our aims on combining datasets with different spatial and spectral resolutions in an effective and as-general-as-possible way, with as little …


Simulating Cambrian Climate: The Significance Of Atmospheric Co2 Concentration And Continental Position, Grace Cutting Jul 2021

Simulating Cambrian Climate: The Significance Of Atmospheric Co2 Concentration And Continental Position, Grace Cutting

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The Cambrian Period began approximately 541 million years ago, and is known for the “Cambrian Explosion”, a time when multicellular life began to rapidly diversify. There is natural historic evidence (isotopes, rock formations, and fossils) that suggests the Cambrian Period experienced a warm climate. However, there is also conflicting evidence that the Cambrian climate may have undergone freezing and thawing cycles, with ice possibly present near the equator. It is critical to understand how ecosystems were able to adapt to past climate changes, especially when analyzing the impacts of modern human activity on climate. Climate model simulations were run to …


An Integrative Model For Soil Biogeochemistry And Methane Processes: I. Model Structure And Sensitivity Analysis, Daniel M. Ricciuto, Xiaofeng Xu, Xiaoying Shi, Yihui Wang, Xia Song, Christopher W. Schadt, Natalie A. Griffiths, Jiafu Mao, Jeffrey M. Warren, Peter E. Thornton, Jeff Chanton, Jason K. Keller, Scott D. Bridgham, Jessica Gutknecht, Stephen D. Sebestyen, Adrien Finzi, Randall Kolka, Paul J. Hanson Jul 2021

An Integrative Model For Soil Biogeochemistry And Methane Processes: I. Model Structure And Sensitivity Analysis, Daniel M. Ricciuto, Xiaofeng Xu, Xiaoying Shi, Yihui Wang, Xia Song, Christopher W. Schadt, Natalie A. Griffiths, Jiafu Mao, Jeffrey M. Warren, Peter E. Thornton, Jeff Chanton, Jason K. Keller, Scott D. Bridgham, Jessica Gutknecht, Stephen D. Sebestyen, Adrien Finzi, Randall Kolka, Paul J. Hanson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Environmental changes are anticipated to generate substantial impacts on carbon cycling in peatlands, affecting terrestrial-climate feedbacks. Understanding how peatland methane (CH4) fluxes respond to these changing environments is critical for predicting the magnitude of feedbacks from peatlands to global climate change. To improve predictions of CH4 fluxes in response to changes such as elevated atmospheric CO2 concentrations and warming, it is essential for Earth system models to include increased realism to simulate CH4 processes in a more mechanistic way. To address this need, we incorporated a new microbial-functional group-based CH4 module into the Energy …


Assimilation Of Seasonal Moisture Variability In North America And Asia For The Last Millennium, Chang Liu Jul 2021

Assimilation Of Seasonal Moisture Variability In North America And Asia For The Last Millennium, Chang Liu

Graduate Theses and Dissertations

The seasonal tree-ring chronologies that recorded discrete moisture signal for warm and cool season have been used to reconstruct the North America Seasonal Precipitation Atlas (NASPA) by the point-by-point regression method, and the results indicated that they can fairly reproduce the seasonal precipitation variability in the past. Compared with reconstructions using only paleoclimate proxy data, the paleoclimate data assimilation (PDA) considers both proxy data and climate model output, so the PDA reconstructions are consistent with both the climate signals reflected by the proxy data and the physical mechanisms represented by climate models. Based on the tree rings with discrete seasonal …


Droughtscape, Summer 2021, National Drought Mitigation Center Jul 2021

Droughtscape, Summer 2021, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Summer 2021


The Effect Of Urbanization On Temperature Indices In The Philippines, John A. Manalo, Jun Matsumoto, Hiroshi G. Takahashi, Marcelino Q. Villafuerte Ii, Lyndon Mark P. Olaguera, Guoyu Ren, Thelma Cinco Jun 2021

The Effect Of Urbanization On Temperature Indices In The Philippines, John A. Manalo, Jun Matsumoto, Hiroshi G. Takahashi, Marcelino Q. Villafuerte Ii, Lyndon Mark P. Olaguera, Guoyu Ren, Thelma Cinco

Physics Faculty Publications

This paper presents a comprehensive analysis of the effect of urbanization on the surface air temperature (SAT) from 1951 to 2018 in the Philippines. The daily minimum temperature (Tmin) and daily maximum temperature (Tmax) records from 34 meteorological stations were used to derive extreme temperature indices. These stations were then classified as urban or rural based on satellite night-lights. The results showed a significant difference in the SAT trends between urban and rural stations, indicative of the effect of urbanization in the country. Larger and more significant warming trends were observed in indices related …


Eastward-Propagating Planetary Waves In The Middle Atmosphere During Major Sudden Stratospheric Warming Events, Christian Todd Rhodes May 2021

Eastward-Propagating Planetary Waves In The Middle Atmosphere During Major Sudden Stratospheric Warming Events, Christian Todd Rhodes

Electronic Theses and Dissertations

No abstract provided.


Characterizing The Northern Hemisphere Circumpolar Vortex Through Space And Time, Nazla Bushra May 2021

Characterizing The Northern Hemisphere Circumpolar Vortex Through Space And Time, Nazla Bushra

LSU Doctoral Dissertations

This hemispheric-scale, steering atmospheric circulation represented by the circumpolar vortices (CPVs) are the middle- and upper-tropospheric wind belts circumnavigating the poles. Variability in the CPV area, shape, and position are important topics in geoenvironmental sciences because of the many links to environmental features. However, a means of characterizing the CPV has remained elusive. The goal of this research is to (i) identify the Northern Hemisphere CPV (NHCPV) and its morphometric characteristics, (ii) understand the daily characteristics of NHCPV area and circularity over time, (iii) identify and analyze spatiotemporal variability in the NHCPV’s centroid, and (iv) analyze how CPV features relate …


Downscaling Methodology For Satellite Land Surface Temperatures Over Urban Environments, Naved Khan, Ruben Vecino May 2021

Downscaling Methodology For Satellite Land Surface Temperatures Over Urban Environments, Naved Khan, Ruben Vecino

Publications and Research

The objective of this study is to develop high spatial and temporal resolution Land Surface Temperature (LST) data using a combination of Landsat 8, infrared satellite sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS), and the Geostationary Operational Environmental Satellite-R Series (GOES-16). The Landsat 8 Thermal Infrared Sensor (TIRS) provides higher spatial resolution (30 m) estimates of skin temperature every 16 days. MODIS makes daytime and nighttime observations of the Earth’s thermal emission at a coarser spatial resolution (1000 m), while GOES-16, which has lower spatial resolution (2 km), measures the skin temperature at a much higher temporal resolution …


Investigating Water Usage Patterns Tied To California State Water Project, Xiaoqing Wu May 2021

Investigating Water Usage Patterns Tied To California State Water Project, Xiaoqing Wu

Publications and Research

California (USA) is the largest agricultural producer and one of the populous states in the United State. As the population and agriculture grows, water consumption patterns become crucial to keep track of especially surface water. In this research project, we studied possible changes in water consumption patterns in different counties and water rights holders who obtain surface water supply from the State Water Project (SWP) in California. We conducted a time series analysis on the California Monthly Diverted Surface Water dataset through two different time series forecasting models. Our analysis indicates that the total diverted surface water presents a periodic …


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 …


Past The Tipping Point, But With Hope Of Return: How Creating A Geoengineering Compulsory Licensing Scheme Can Incentivize Innovation, Brooke Wilson Apr 2021

Past The Tipping Point, But With Hope Of Return: How Creating A Geoengineering Compulsory Licensing Scheme Can Incentivize Innovation, Brooke Wilson

Washington and Lee Journal of Civil Rights and Social Justice

This Note explores the patenting of geoengineering technologies and issues arising from the early stages of this high-risk, high-reward technology. This Note focuses on one possible solution to solving the issues surrounding the patenting of geoengineering technology: Creating a specialized compulsory licensing scheme.


Hazardous Weather Communication En Español: Challenges, Current Resources, And Future Practices, Joseph E. Trujillo-Falcón, Orlando Bermúdez, Krizia Negrón-Hernández, John Lipski, Elizabeth Leitman, Kodi Berry Apr 2021

Hazardous Weather Communication En Español: Challenges, Current Resources, And Future Practices, Joseph E. Trujillo-Falcón, Orlando Bermúdez, Krizia Negrón-Hernández, John Lipski, Elizabeth Leitman, Kodi Berry

National Oceanographic and Atmospheric Administration: Technical Reports and Related Materials

According to recent Census data, the Hispanic or Latino population represents nearly 1 in 5 Americans today, where 71.1% of these individuals speak Spanish at home. Despite increased efforts among the weather enterprise, establishing effective risk communication strategies for Spanish-speaking populations has been an uphill battle. No frameworks exist for translating weather information into the Spanish language, nor are there collective solutions that address this problem within the weather world. The objective of this article is threefold. First, the current translation issue in Spanish is highlighted. Through research conducted at the NOAA/NWS Storm Prediction Center, situations are revealed where regional …


Droughtscape, Spring 2021, National Drought Mitigation Center Apr 2021

Droughtscape, Spring 2021, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Spring 2021


Investigating Decadal Changes Of Multiple Hydrological Products And Land-Cover Changes In The Mediterranean Region For 2009–2018, Wenzhao Li, Sachi Perera, Erik Linstead, Rejoice Thomas, Hesham El-Askary, Thomas Piechota, Daniele Struppa Mar 2021

Investigating Decadal Changes Of Multiple Hydrological Products And Land-Cover Changes In The Mediterranean Region For 2009–2018, Wenzhao Li, Sachi Perera, Erik Linstead, Rejoice Thomas, Hesham El-Askary, Thomas Piechota, Daniele Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Land-cover change is a critical concern due to its climatic, ecological, and socioeconomic consequences. In this study, we used multiple variables including precipitation, vegetation index, surface soil moisture, and evapotranspiration obtained from different satellite sources to study their association with land-cover changes in the Mediterranean region. Both observational and modeling data were used for climatology and correlation analysis. Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS) and Global Land Data Assimilation System (GLDAS) were used to extract surface soil moisture and evapotranspiration data. Intercomparing the results of FLDAS and GLDAS suggested that FLDAS data had better …


Representing Methane Emissions From Wet Tropical Forest Soils Using Microbial Functional Groups Constrained By Soil Diffusivity, Debjani Sihi, Xiaofeng Xu, Mónica Salazar Ortiz, Christine S. O'Connell, Whendee L. Silver, Carla López-Lloreda, Julia M. Brenner, Ryan K. Quinn, Jana R. Phillips, Brent D. Newman, Melanie A. Mayes Mar 2021

Representing Methane Emissions From Wet Tropical Forest Soils Using Microbial Functional Groups Constrained By Soil Diffusivity, Debjani Sihi, Xiaofeng Xu, Mónica Salazar Ortiz, Christine S. O'Connell, Whendee L. Silver, Carla López-Lloreda, Julia M. Brenner, Ryan K. Quinn, Jana R. Phillips, Brent D. Newman, Melanie A. Mayes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical ecosystems contribute significantly to global emissions of methane (CH4), and landscape topography influences the rate of CH4 emissions from wet tropical forest soils. However, extreme events such as drought can alter normal topographic patterns of emissions. Here we explain the dynamics of CH4 emissions during normal and drought conditions across a catena in the Luquillo Experimental Forest, Puerto Rico. Valley soils served as the major source of CH4 emissions in a normal precipitation year (2016), but drought recovery in 2015 resulted in dramatic pulses in CH4 emissions from all topographic positions. Geochemical parameters …


Ecological Risk Assessment Of Managed Relocation As A Climate Change Adaptation Strategy, Aviv Karasov-Olson, Mark W. Schwartz, Julian D. Olden, Sarah Skikne, Jessica J. Hellmann, Sarah Allen, Christy Brigham, Danielle Buttke, David J. Lawrence, Abraham J. Miller-Rushing, Jeffrey T. Morisette, Gregor W. Schuurman, Melissa Trammell, Cat Hawkins Hoffman Mar 2021

Ecological Risk Assessment Of Managed Relocation As A Climate Change Adaptation Strategy, Aviv Karasov-Olson, Mark W. Schwartz, Julian D. Olden, Sarah Skikne, Jessica J. Hellmann, Sarah Allen, Christy Brigham, Danielle Buttke, David J. Lawrence, Abraham J. Miller-Rushing, Jeffrey T. Morisette, Gregor W. Schuurman, Melissa Trammell, Cat Hawkins Hoffman

United States National Park Service: Publications

Executive Summary

Changing climate and introduced species are placing an increasing number of species at risk of extinction. Increasing extinction risk is increasing calls to protect species by relocating, or translocating, them to locations with more favorable biotic or climatic conditions. Managed relocation, or assisted migration, of species entails risks to both the conservation target organisms being moved as well as the recipient ecosystems into which they are moved.

Recognizing this risk, calls have been made for practitioners interested in considering a managed relocation project to engage in a serious risk assessment prior to advancing a project. We engaged a …


Comprehensive Record Of Volcanic Eruptions In The Holocene (11,000 Years) From The Wais Divide, Antarctica Ice Core, Jihong Cole-Dai, David G. Harris, Joshua A. Kennedy, Michael Sigl, Joseph R. Mcconnell, T. J. Fudge, Lei Geng, Olivia J. Maselli, Kendrick C. Taylor, Joseph M. Souney Mar 2021

Comprehensive Record Of Volcanic Eruptions In The Holocene (11,000 Years) From The Wais Divide, Antarctica Ice Core, Jihong Cole-Dai, David G. Harris, Joshua A. Kennedy, Michael Sigl, Joseph R. Mcconnell, T. J. Fudge, Lei Geng, Olivia J. Maselli, Kendrick C. Taylor, Joseph M. Souney

Ice Core and Environmental Chemistry Lab Datasets and Publications

A comprehensive record (WHV2020) of explosive volcanic eruptions in the last 11,000 years is reconstructed from the West Antarctica Ice Sheet Divide deep ice core (WDC). The chronological list of 426 large volcanic eruptions in the Southern Hemisphere and the low latitudes during the Holocene are of the highest quality of all volcanic records from ice cores, owing to the high-resolution chemical measurement of the ice core and the exceptionally accurate WDC timescale. No apparent trend is found in the frequency (number of eruptions per millennium) of volcanic eruptions, and the number of eruptions in the most recent millennium (1,000–2,000 …


Diurnal Cycle Of Passive Microwave Brightness Temperatures Over Land At A Global Scale, Zahra Sharifnezhad, Hamid Norouzi, Satya Prakash, Reginald Blake, Reze Khanbilvard Feb 2021

Diurnal Cycle Of Passive Microwave Brightness Temperatures Over Land At A Global Scale, Zahra Sharifnezhad, Hamid Norouzi, Satya Prakash, Reginald Blake, Reze Khanbilvard

Publications and Research

Satellite-borne passive microwave radiometers provide brightness temperature (TB) measurements in a large spectral range which includes a number of frequency channels and generally two polarizations: horizontal and vertical. These TBs are widely used to retrieve several atmospheric and surface variables and parameters such as precipitation, soil moisture, water vapor, air temperature profile, and land surface emissivity. Since TBs are measured at different microwave frequencies with various instruments and at various incidence angles, spatial resolutions, and radiometric characteristics, a mere direct integration of them from different microwave sensors would not necessarily provide consistency. However, when appropriately harmonized, they can provide a …


Odu Professors Study Gulf Stream Decline, News @ Odu Jan 2021

Odu Professors Study Gulf Stream Decline, News @ Odu

News Items

No abstract provided.


A Model-Based Exploratory Study Of Sulfur Dioxide Dispersions From Concentrated Animal Feeding Operations In The Southeastern United States, Jesse Winchester, Rezaul Mahmood, William Rodgers, Philip J. Silva, Nanh Lovanh, Joshua D. Durkee, John Loughrin Jan 2021

A Model-Based Exploratory Study Of Sulfur Dioxide Dispersions From Concentrated Animal Feeding Operations In The Southeastern United States, Jesse Winchester, Rezaul Mahmood, William Rodgers, Philip J. Silva, Nanh Lovanh, Joshua D. Durkee, John Loughrin

High Plains Regional Climate Center: Staff Publications

In the Southeastern U. S. there are Concentrated Animal Feeding Operations (CAFOs) that emit a variety of gases, including SO2. Sulfur is emitted as reduced sulfur compounds and can react in the atmosphere to produce SO2. It is expected that the concentra­tion and spread of SO2 emissions from these sources would differ between wet and dry periods. In this research, SO2 emissions from locations representing CAFOs and its dispersion over the south­eastern U.S. were simulated through sensitivity experiments using the Weather Research and Forecasting-Chemistry (WRF- Chem) model. Simulations were performed for dry periods and …


The Role Of Oxygen In Stimulating Methane Production In Wetlands, Jared L. Wilmoth, Jeffra K. Schaefer, Danielle R. Schlesinger, Spencer W. Roth, Patrick G. Hatcher, Julie K. Shoemaker, Xinning Zhang Jan 2021

The Role Of Oxygen In Stimulating Methane Production In Wetlands, Jared L. Wilmoth, Jeffra K. Schaefer, Danielle R. Schlesinger, Spencer W. Roth, Patrick G. Hatcher, Julie K. Shoemaker, Xinning Zhang

Chemistry & Biochemistry Faculty Publications

Methane (CH4), a potent greenhouse gas, is the second most important greenhouse gas contributor to climate change after carbon dioxide (CO2). The biological emissions of CH4 from wetlands are a major uncertainty in CH4 budgets. Microbial methanogenesis by Archaea is an anaerobic process accounting for most biological CH4 production in nature, yet recent observations indicate that large emissions can originate from oxygenated or frequently oxygenated wetland soil layers. To determine how oxygen (O2) can stimulate CH4 emissions, we used incubations of Sphagnum peat to demonstrate that the temporary exposure of …


Droughtscape, Winter 2021, National Drought Mitigation Center Jan 2021

Droughtscape, Winter 2021, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Winter 2021


Examining Co2 Model Observation Residuals Using Act-America Data, Tobias Gerken, Sha Feng, Klaus Keller, Thomas Lauvaux, Joshua P. Digangi, Yonhoon Choi, Bianca Baier, Kenneth J. Davis Jan 2021

Examining Co2 Model Observation Residuals Using Act-America Data, Tobias Gerken, Sha Feng, Klaus Keller, Thomas Lauvaux, Joshua P. Digangi, Yonhoon Choi, Bianca Baier, Kenneth J. Davis

School of Integrated Sciences - Faculty Scholarship

An edited version of this paper was published by AGU. Copyright (2021) American Geophysical Union.

Please refer to:
Gerken, Tobias, Sha Feng, Klaus Keller, Thomas Lauvaux, Joshua P. DiGangi, Yonghoon Choi, Bianca Baier, and Kenneth J. Davis. Examining CO2 Model Observation Residuals Using ACT-America Data. Journal of Geophysical Research: Atmospheres 126, no.18 (2021): e2020JD034481. https://doi.org/10.1029/2020JD034481

Atmospheric CO2 inversion typically relies on the specification of prior flux and atmospheric model transport errors, which have large uncertainties. Here, we used ACT-America airborne observations to compare CO2 model-observation mismatch in the eastern U.S. and during four climatological seasons for the mesoscale …


Fifteen Years Of Hfc-134a Satellite Observations: Comparisons With Slimcat Calculations, Jeremy J. Harrison, Martyn P. Chipperfield, Christopher D. Boone, Sandip S. Dhomse, Peter F. Bernath Jan 2021

Fifteen Years Of Hfc-134a Satellite Observations: Comparisons With Slimcat Calculations, Jeremy J. Harrison, Martyn P. Chipperfield, Christopher D. Boone, Sandip S. Dhomse, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

The phase out of anthropogenic ozone-depleting substances such as chlorofluorocarbons under the terms of the Montreal Protocol led to the development and worldwide use of hydrofluorocarbons (HFCs) in refrigeration, air conditioning, and as blowing agents and propellants. Consequently, over recent years, the atmospheric abundances of HFCs have dramatically increased. HFCs are powerful greenhouse gases and are now controlled under the terms of the 2016 Kigali Amendment to the Montreal Protocol. HFC-134a is currently the most abundant HFC in the atmosphere, breaking the 100 ppt barrier in 2018, and can be measured in the Earth's atmosphere by the satellite remote-sensing instrument …


Particle Identification Of Pyro-Convection From Wildfires, Justin Province Jan 2021

Particle Identification Of Pyro-Convection From Wildfires, Justin Province

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.


Activation Scavenging Of Aerosol : Effect Of Turbulence And Aerosol-Composition, Abu Sayeed Md Shawon Jan 2021

Activation Scavenging Of Aerosol : Effect Of Turbulence And Aerosol-Composition, Abu Sayeed Md Shawon

Dissertations, Master's Theses and Master's Reports

The interaction of aerosol particles with solar radiation significantly contributes to the global radiation balance. The magnitude of this aerosol-radiation interaction, among other parameters, depends on different aerosol properties, including how readily these particles would act as cloud condensation nuclei (CCN). These properties are governed by the formation and scavenging processes of aerosol. This dissertation explores some of these scavenging processes.

Favorable humidity and preexisting aerosol particles acting as CCN are the sine qua non conditions to form cloud droplets in Earth’s atmosphere. Forming cloud droplets (known as activation), meanwhile, acts as a wet scavenging mechanism for those CCN. Given …


Developing A Tourism Opportunity Index Regarding The Prospective Of Overtourism In Nepal, Susan Phuyal Dec 2020

Developing A Tourism Opportunity Index Regarding The Prospective Of Overtourism In Nepal, Susan Phuyal

Graduate Theses/Dissertations

This research explores Nepal's overtourism scenario based on the capacity of a locality to manage sustainable tourism practices. Environmental degradation, local infrastructure degradation, negative tourist experience and local resident responses regarding visitors are the four main variables used in this study to analyze overtourism. In order to analyze the case study of overtourism, we select the three top touristic cities of Nepal, Kathmandu, Pokhara, and Chitwan based on the number of annual visitors. Nepal's case analysis of overtourism conditions reviews the overall threat of over-tourism and establishes a metric by which tourism can be viewed as potentially detrimental to sustainability. …


Mass And Number Size Distributions Of Rbc In Snow And Firn Samples From Pine Island Glacier, West Antarctica, Luciano Marquetto, Susan Kaspari, Jefferson Cardia Simões Nov 2020

Mass And Number Size Distributions Of Rbc In Snow And Firn Samples From Pine Island Glacier, West Antarctica, Luciano Marquetto, Susan Kaspari, Jefferson Cardia Simões

Geological Sciences Faculty Scholarship

An extended‐range Single Particle Soot Photometer (SP2) coupled to a Marin‐5 nebulizer was used to measure the refractory black carbon (rBC) mass and number size distributions in 1,004 samples from a West Antarctica snow/firn core. The SP2 was calibrated using Aquadag and a Centrifugal Particle Mass Analyzer for BC particles ranging from 0.5 to 800 fg. Our results indicate a significant contribution of rare, large particles of mass‐equivalent diameter (DBC) > 500 nm to the total rBC mass (36%), while small particles (DBC < 100 nm) are abundant but contribute <8% to total rBC mass. We observed a primary mass median diameter of 162 ± 40 nm, smaller than reported for snow in other regions of the globe but similar to East Antarctica rBC size distributions. In addition, we observed other modes at 673, 1,040, and >1,810 nm (uncontained mode). We compared two sets of samples from different seasons …