Open Access. Powered by Scholars. Published by Universities.®

2017

Discipline
Institution
Keyword
Publication
Publication Type

Articles 91 - 120 of 169

Full-Text Articles in Climate

Characterizing South American Mesoscale Convective Complexes Using Isotope Hydrology, Kyle J. Hogancamp Apr 2017

Characterizing South American Mesoscale Convective Complexes Using Isotope Hydrology, Kyle J. Hogancamp

Masters Theses & Specialist Projects

Mesoscale convective complexes (MCCs) over subtropical South America contribute an average annual volume of precipitation equal to approximately seven km3 and occur with an average regularity in the region, with more than 30 per warm season. Isotopic characteristics of precipitation, such as δ2H and δ18O values, provide information that can be used to identify unique processes and sources related to precipitation events. The largest database of isotope characteristics of precipitation within the region is the Global Network of Isotopes in Precipitation (GNIP), which provides varying temporal resolution data from stations around the world, including subtropical South America.

Using this database, …


Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani Apr 2017

Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani

Department of Geography: Dissertations, Theses, and Student Research

The gross primary production (GPP) metric is useful in determining trends in the terrestrial carbon cycle. Models that determine GPP utilizing the light use efficiency (LUE) approach in conjunction with biophysical parameters that account for local weather conditions and crop specific factors are beneficial in that they combine the accuracy of the biophysical model with the versatility of the LUE model. One such model developed using in situ data was adapted to operate with remote sensing derived leaf area index (LAI) data and gridded weather datasets. The model, known as the Light Use Efficiency GPP Model (EGM), uses a four …


Droughtscape, Spring 2017, National Drought Mitigation Center Apr 2017

Droughtscape, Spring 2017, National Drought Mitigation Center

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

Contents

Drought center helps islands reduce drought vulnerability

2017 sees above-average precipitation, warmer temps

California pulls out of drought

After tech transfer, training Tunisia launches first drought map

Drought center releases 2016 annual report

Book chapter focuses on drought and health

U2U wraps up, brings useful tools to farmers

Survey finds drought info leads to better decisions


Climate Change, Natural Disasters, And Suicide: A Systematic Review, Ans Irfan, Peter Lapuma Apr 2017

Climate Change, Natural Disasters, And Suicide: A Systematic Review, Ans Irfan, Peter Lapuma

GW Research Days 2016 - 2020

Background.
Natural disasters are projected to increase due to climate change. Mental health is not a well-researched area in public health, particularly as it relates to environmental health and in the aftermath of natural disasters. The suicide rate is approximately 13 per 100,000 people in the US, nationally. This already high suicide rate warrants researching this area mental health. Understanding the relation between natural disasters and suicide rates might help alleviate human suffering and potentially save lives in the future, in post-disaster settings. This research will further the knowledge of the association between natural disasters and suicide and provide foundation …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- April 2017, Natalie Umphlett, Crystal J. Stiles Apr 2017

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- April 2017, Natalie Umphlett, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the interim director........................................1

Staff spotlight...........................1

Fisheries & wildlife climate workshop...................................2

Product highlights..................3

AWDN information.................4

Update on regional climate conditions..................................4

NCA workshop and outreach activities......................................5

Recent and upcoming travel and activities.............................6


Investigating The Magnitude And Range Of The Urban Heat Island Within Gettysburg, Pennsylvania, Samuel S. Thompson, Rachel A. Wilkins Apr 2017

Investigating The Magnitude And Range Of The Urban Heat Island Within Gettysburg, Pennsylvania, Samuel S. Thompson, Rachel A. Wilkins

Student Publications

Cities experience UHIs due to the thermal properties (albedo, thermal emittance, radiative flux, and heat capacity) of human-made substances and urban geometry. This study investigated the existence of an urban heat island (UHI) in Gettysburg, Pennsylvania. The goal of this project was to assess whether a small-scale city like Gettysburg demonstrates an UHI effect and, if present, the extent and magnitude of the UHI. We hypothesized that (1) temperatures within the city are significantly higher than the surrounding area, (2) the magnitude of the UHI will diminish as distance from the city center increases, and (3) the UHI will not …


Separating Decadal Global Water Cycle Variability From Sea Level Rise, B. D. Hamlington, J. T. Reager, M.-H. Lo, K. B. Karnauskas, R. R. Leben Apr 2017

Separating Decadal Global Water Cycle Variability From Sea Level Rise, B. D. Hamlington, J. T. Reager, M.-H. Lo, K. B. Karnauskas, R. R. Leben

CCPO Publications

Under a warming climate, amplification of the water cycle and changes in precipitation patterns over land are expected to occur, subsequently impacting the terrestrial water balance. On global scales, such changes in terrestrial water storage (TWS) will be reflected in the water contained in the ocean and can manifest as global sea level variations. Naturally occurring climate-driven TWS variability can temporarily obscure the long-term trend in sea level rise, in addition to modulating the impacts of sea level rise through natural periodic undulation in regional and global sea level. The internal variability of the global water cycle, therefore, confounds both …


Getting That Sinking Feeling: Analysis And Impacts Of Sea Level Rise On Three National Parks Along The East Coast, Usa, Julia K. Deros, Amanda L. Thibault, Amy B. True Apr 2017

Getting That Sinking Feeling: Analysis And Impacts Of Sea Level Rise On Three National Parks Along The East Coast, Usa, Julia K. Deros, Amanda L. Thibault, Amy B. True

Student Publications

Due to global climate change, sea level rise (SLR) has become a threat for future generations, but the extent of this danger is unknown. To help understand the possible effects of SLR on the east coast of the United States, we studied three national parks: Acadia National Park (ACAD), Assateague Island National Seashore (ASIS) and Everglades National Park (EVER). We predicted that ACAD would be less affected by SLR than ASIS and EVER due to the construction of its beach profile. By measuring the beach profile, we found that Sand Beach in ACAD was reflective with an average slope of …


Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger Mar 2017

Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger

USF Tampa Graduate Theses and Dissertations

The development of an accurate and precise geochronology is imperative to understanding archives containing information about Earth’s past. Unable to date all intervals of an archive, researchers use methods of interpolation to approximate age between dates. Sections of the radiocarbon calibration curve can induce larger chronological uncertainty independent of instrumental precision, meaning even a precise date may carry inflated error in its calibration to a calendar age. Methods of interpolation range from step-wise linear regression to, most recently, Bayesian statistical models. These employ prior knowledge of accumulation rate to provide a more informed interpolation between neighboring dates. This study uses …


Geographic Variation Of Cirques On Iceland: Factors Influencing Cirque Morphology, Heather A. Ipsen, Rachael E. Grube, Jessica F. Lee, Sarah M. Principato Mar 2017

Geographic Variation Of Cirques On Iceland: Factors Influencing Cirque Morphology, Heather A. Ipsen, Rachael E. Grube, Jessica F. Lee, Sarah M. Principato

Environmental Studies Faculty Publications

Cirques are one of the most common glacial landforms in alpine settings. They also provide important paleoclimate information (e.g. Meierding 1984; Evans 2006). The purpose of this study is to fill in gaps in the climate record of Iceland by conducting a quantitative analysis of cirques in three regions in Iceland: Tröllaskagi, the East Fjords, and Vestfirðir. Iceland, located in the center of the North Atlantic Ocean, contains many small glaciers, in addition to large ice caps. The glaciers on Iceland are particularly sensitive to variations in oceanic and atmospheric circulation (Andresen et al. 2005; Geirsdóttir et al., 2009; Ólafsdóttir …


New Constraints On The Timing And Pattern Of Deglaciation In The Húnaflói Bay Region Of Northwest Iceland Using Cosmogenic 36ca Dating And Geomorphic Mapping, Amanda N. Houts, Joseph M. Licciardi, Sarah M. Principato, Susan H. Zimmerman, Robert C. Finkel Mar 2017

New Constraints On The Timing And Pattern Of Deglaciation In The Húnaflói Bay Region Of Northwest Iceland Using Cosmogenic 36ca Dating And Geomorphic Mapping, Amanda N. Houts, Joseph M. Licciardi, Sarah M. Principato, Susan H. Zimmerman, Robert C. Finkel

Environmental Studies Faculty Publications

Understanding the evolution and timing of changes in ice sheet geometry and extent in Iceland during the Last Glacial Maximum (LGM) and subsequent deglaciation continues to stimulate much active research. Though many previous studies have advanced our knowledge of Icelandic ice sheet history preserved in marine and terrestrial settings (e.g., Andrews et al., 2000; Norðdahl et al., 2008), the timing of ice margin retreat remains largely unknown in several key regions. Recently published 36Cl surface exposure ages of bedrock surfaces and moraines in the West Fjords (Brynjólfsson et al., 2015) contribute important progress in establishing more precise age control of …


How Lessons From A Past Disaster Can Influence Resilience And Climate Adaptation In Broward County, Florida, Hannah Rose Torres Mar 2017

How Lessons From A Past Disaster Can Influence Resilience And Climate Adaptation In Broward County, Florida, Hannah Rose Torres

USF Tampa Graduate Theses and Dissertations

In the face of future uncertainties, many places are struggling with decisions about how to prepare for and adapt to climate change. The purpose of this research is to shed light on the concept of resilience, and uncover lessons for resilience-building exposed by a past disaster, Hurricane Wilma.

The dissertation begins with an introduction (Chapter 1) detailing the research problem, key terms and overall research design. The study was conducted in three distinct phases. The first phase (Chapter 2), explored the concept of resilience to understand how it was defined in three South Florida communities. Content analyses of city and …


On The Relationship Between Spring Nao And Snowmelt In The Upper Southwestern United States, Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos Mar 2017

On The Relationship Between Spring Nao And Snowmelt In The Upper Southwestern United States, Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study examines the relationship between the North Atlantic Oscillation (NAO) and snowmelt in spring in the upper southwestern states of the United States (UP_SW) including California, Nevada, Utah, and Colorado, using SNOTEL datasets for 34 yr (1980–2014). Statistically significant negative correlations are found between NAO averages in the snowmelt period and timings of snowmelt (i.e., positive NAO phases in spring enhance snowmelt, and vice versa). It is also found that correlations between El Niño–Southern Oscillation and snowmelt are negligible in the region. The NAO–snowmelt relationship is most pronounced below the 2800-m level; above this level, the relationship becomes weaker. …


P07. Characterizing The Purple Crow Lidar To Investigate Potential Sources Of Wet Bias, Jeffrey Vankerkhove, Robert J. Sica, Robin Wing, Steve Argall Mar 2017

P07. Characterizing The Purple Crow Lidar To Investigate Potential Sources Of Wet Bias, Jeffrey Vankerkhove, Robert J. Sica, Robin Wing, Steve Argall

Western Research Forum

The Purple Crow Lidar is a large aperture lidar, capable of retrieving water vapor profiles into the stratosphere. Water vapor in the upper Troposphere-Lower Stratosphere (UTLS) region is of particular importance in understanding Earth's radiative budget and atmospheric dynamics, making accurate UTLS measurements crucial. A comparison campaign with the NASA/GSFC ALVICE mobile lidar in the spring of 2012 showed PCL water vapor measurements were consistently larger than those of ALVICE in the lower stratosphere, prompting an investigation to characterize the system. The investigation looks into how changes to the data processing approach, as well as applying additional instrumental corrections, would …


P16. Ralmo Rotational Raman Temperature Retrieval: First Steps Towards The Application Of Optimal Estimation Method (Oem), Shayamila N. Mahagammulla Gamage, Robert Sica, Alexander Haefele Mar 2017

P16. Ralmo Rotational Raman Temperature Retrieval: First Steps Towards The Application Of Optimal Estimation Method (Oem), Shayamila N. Mahagammulla Gamage, Robert Sica, Alexander Haefele

Western Research Forum

Background:

Temperature is an important atmospheric parameter that plays an extensive role in the fields of atmospheric dynamics, climatology, meteorology, and chemistry. Light detection and ranging (lidar), is a remote sensing technology that can be used for atmospheric temperature profiling. A lidar transmits short laser pulses into the atmosphere and the light scattered by the particles in the atmosphere is collected and measured using a telescope. The atmospheric temperatures can be retrieved by analysing the Pure Rotational Raman (PRR) scatter measurements from the nitrogen and oxygen molecules in the atmosphere.

Methods:

In this study use the Optimal Estimation Method (OEM) …


Predicting The U.S. Drought Monitor Using Precipitation, Soil Moisture, And Evapotranspiration Anomalies. Part Ii: Intraseasonal Drought Intensification Forecasts, David J. Lorenz, Jason A. Otkin, Mark Svoboda, Christopher R. Hain, Martha C. Anderson, Yafang Zhong Mar 2017

Predicting The U.S. Drought Monitor Using Precipitation, Soil Moisture, And Evapotranspiration Anomalies. Part Ii: Intraseasonal Drought Intensification Forecasts, David J. Lorenz, Jason A. Otkin, Mark Svoboda, Christopher R. Hain, Martha C. Anderson, Yafang Zhong

National Drought Mitigation Center: Faculty Publications

Probabilistic forecasts of U.S. Drought Monitor (USDM) intensification over 2-, 4-, and 8-week time periods are developed based on recent anomalies in precipitation, evapotranspiration, and soil moisture. These statistical forecasts are computed using logistic regression with cross validation. While recent precipitation, evapotranspiration, and soil moisture do provide skillful forecasts, it is found that additional information on the current state of the USDM adds significant skill to the forecasts. The USDM state information takes the form of a metric that quantifies the ‘‘distance’’ from the next-higher drought category using a nondiscrete estimate of the current USDM state. This adds skill because …


Dynamical Conditions Of Ice Supersaturation And Ice Nucleation In Convective Systems: A Comparative Analysis Between In Situ Aircraft Observations And Wrf Simulations, John D'Alessandro, Minghui Diao, Chenglai Wu, Xiaohong Liu, Ming Chen, Hugh Morrison, Trude Eidhammer, Jorgen Jensen, Aaron Bansemer, Mark Zondlo, Joshua Digangi Mar 2017

Dynamical Conditions Of Ice Supersaturation And Ice Nucleation In Convective Systems: A Comparative Analysis Between In Situ Aircraft Observations And Wrf Simulations, John D'Alessandro, Minghui Diao, Chenglai Wu, Xiaohong Liu, Ming Chen, Hugh Morrison, Trude Eidhammer, Jorgen Jensen, Aaron Bansemer, Mark Zondlo, Joshua Digangi

Faculty Publications, Meteorology and Climate Science

Occurrence frequency and dynamical conditions of ice supersaturation (ISS, where relative humidity with respect to ice (RHi) > 100%) are examined in the upper troposphere around convective activity. Comparisons are conducted between in situ airborne observations and the Weather Research and Forecasting model simulations using four double‐moment microphysical schemes at temperatures ≤ −40°C. All four schemes capture both clear‐sky and in‐cloud ISS conditions. However, the clear‐sky (in‐cloud) ISS conditions are completely (significantly) limited to the RHi thresholds of the Cooper parameterization. In all of the simulations, ISS occurrence frequencies are higher by ~3–4 orders of magnitude at higher updraft speeds ( …


Umphlett Qci March 2017, Natalie Umphlett Mar 2017

Umphlett Qci March 2017, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Mountain Snowpack

Christmas Day Storm

Heavy Fuels Increase Fire Risk

Early Warmth Causes Concerns

3-Month Precipitation and Temperature Outlooks

NOAA Spring Flood Outlook


Mass Coral Mortality Under Local Amplification Of 2 °C Ocean Warming, Thomas M. Decarlo, Anne L. Cohen, George T. F. Wong, Kristen A. Davis, Pat Lohman, Keryea Soong Mar 2017

Mass Coral Mortality Under Local Amplification Of 2 °C Ocean Warming, Thomas M. Decarlo, Anne L. Cohen, George T. F. Wong, Kristen A. Davis, Pat Lohman, Keryea Soong

OES Faculty Publications

A 2 °C increase in global temperature above pre-industrial levels is considered a reasonable target for avoiding the most devastating impacts of anthropogenic climate change. In June 2015, sea surface temperature (SST) of the South China Sea (SCS) increased by 2 °C in response to the developing Pacific El Nino. On its own, this moderate, short-lived warming was unlikely to cause widespread damage to coral reefs in the region, and the coral reef "Bleaching Alert" alarm was not raised. However, on Dongsha Atoll, in the northern SCS, unusually weak winds created low-flow conditions that amplified the 2 °C basin-scale …


Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity, And Export, Daniel E. Kaufman, Marjorie A. M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C. P. Hemmings Mar 2017

Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity, And Export, Daniel E. Kaufman, Marjorie A. M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C. P. Hemmings

CCPO Publications

The Ross Sea, a highly productive region of the Southern Ocean, is expected to experience warming during the next century along with reduced summer sea ice concentrations and shallower mixed layers. This study investigates how these climatic changes may alter phytoplankton assemblage composition, primary productivity, and export. Glider measurements are used to force a one-dimensional biogeochemical model, which includes diatoms and both solitary and colonial forms of Phaeocystis antarctica. Model performance is evaluated with glider observations, and experiments are conducted using projections of physical drivers for mid-21st and late-21st century. These scenarios reveal a 5% increase in primary productivity …


A Walk On The Wild Side: Disturbance Dynamics And The Conservation And Management Of European Mountain Forest Ecosystems, Dominik Kulakowski, Rupert Seidl, Jan Holeksa, Timo Kuuluvainen, Thomas A. Nagel, Momchil Panayotov, Miroslav Svoboda, Simon Thorn, Giorgio Vacchiano, Cathy Whitlock, Thomas Wohlgemuth, Peter Bebi Mar 2017

A Walk On The Wild Side: Disturbance Dynamics And The Conservation And Management Of European Mountain Forest Ecosystems, Dominik Kulakowski, Rupert Seidl, Jan Holeksa, Timo Kuuluvainen, Thomas A. Nagel, Momchil Panayotov, Miroslav Svoboda, Simon Thorn, Giorgio Vacchiano, Cathy Whitlock, Thomas Wohlgemuth, Peter Bebi

Geography

Mountain forests are among the most important ecosystems in Europe as they support numerous ecological, hydrological, climatic, social, and economic functions. They are unique relatively natural ecosystems consisting of long-lived species in an otherwise densely populated human landscape. Despite this, centuries of intensive forest management in many of these forests have eclipsed evidence of natural processes, especially the role of disturbances in long-term forest dynamics. Recent trends of land abandonment and establishment of protected forests have coincided with a growing interest in managing forests in more natural states. At the same time, the importance of past disturbances highlighted in an …


Watershed Response To Climate Change And Fire-Burns In The Upper Umatilla River Basin, Usa, Kimberly Crystal Yazzie, Heejun Chang Feb 2017

Watershed Response To Climate Change And Fire-Burns In The Upper Umatilla River Basin, Usa, Kimberly Crystal Yazzie, Heejun Chang

Geography Faculty Publications and Presentations

This study analyzed watershed response to climate change and forest fire impacts in the upper Umatilla River Basin (URB), Oregon, using the precipitation runoff modeling system. Ten global climate models using Coupled Intercomparison Project Phase 5 experiments with Representative Concentration Pathways (RCP) 4.5 and 8.5 were used to simulate the effects of climate and fire-burns on runoff behavior throughout the 21st century. We observed the center timing (CT) of flow, seasonal flows, snow water equivalent (SWE) and basin recharge. In the upper URB, hydrologic regime shifts from a snow-rain-dominated to rain-dominated basin. Ensemble mean CT occurs 27 days earlier in …


Assessment Of An Atmospheric Transport Model For Annual Inverse Estimates Of California Greenhouse Gas Emissions, Justin Bagley, Seongeun Jeong, Xinguang Cui, Sally Newman, Jingsong Zhang, Chad Priest, Mixtli Campos-Pineda, Arlyn Andrews, Laura Bianco, Matthew Lloyd, Neil Lareau, Craig Clements, Marc Fischer Feb 2017

Assessment Of An Atmospheric Transport Model For Annual Inverse Estimates Of California Greenhouse Gas Emissions, Justin Bagley, Seongeun Jeong, Xinguang Cui, Sally Newman, Jingsong Zhang, Chad Priest, Mixtli Campos-Pineda, Arlyn Andrews, Laura Bianco, Matthew Lloyd, Neil Lareau, Craig Clements, Marc Fischer

Faculty Publications, Meteorology and Climate Science

Atmospheric inverse estimates of gas emissions depend on transport model predictions, hence driving a need to assess uncertainties in the transport model. In this study we assess the uncertainty in WRF-STILT (Weather Research and Forecasting and Stochastic Time-Inverted Lagrangian Transport) model predictions using a combination of meteorological and carbon monoxide (CO) measurements. WRF configurations were selected to minimize meteorological biases using meteorological measurements of winds and boundary layer depths from surface stations and radar wind profiler sites across California. We compare model predictions with CO measurements from four tower sites in California from June 2013 through May 2014 to assess …


Contributions Of Wood Smoke And Vehicle Emissions To Ambient Concentrations Of Volatile Organic Compounds And Particulate Matter During The Yakima Wintertime Nitrate Study, Graham Vanderschelden, Benjamin De Foy, Courtney Herring, Susan D. Kaspari, Tim Vanreken, Bertram Jobson Feb 2017

Contributions Of Wood Smoke And Vehicle Emissions To Ambient Concentrations Of Volatile Organic Compounds And Particulate Matter During The Yakima Wintertime Nitrate Study, Graham Vanderschelden, Benjamin De Foy, Courtney Herring, Susan D. Kaspari, Tim Vanreken, Bertram Jobson

All Faculty Scholarship for the College of the Sciences

A multiple linear regression (MLR) chemical mass balance model was applied to data collected during an air quality field experiment in Yakima, WA, during January 2013 to determine the relative contribution of residential wood combustion (RWC) and vehicle emissions to ambient pollutant levels. Acetonitrile was used as a chemical tracer for wood burning and nitrogen oxides (NOx) as a chemical tracer for mobile sources. RWC was found to be a substantial source of gas phase air toxics in wintertime. The MLR model found RWC primarily responsible for emissions of formaldehyde (73%), acetaldehyde (69%), and black carbon (55%) and mobile sources …


Ozone Depletion, A Big Threat To Climate Change: What Can Be Done?, Sumera Aziz Ali, Savera Aziz Ali, Nadir Suhail Feb 2017

Ozone Depletion, A Big Threat To Climate Change: What Can Be Done?, Sumera Aziz Ali, Savera Aziz Ali, Nadir Suhail

Community Health Sciences

Ozone in the stratosphere is very important as it acts as a safeguard for the earth and protects life from harmful ultraviolet radiations coming from the sun. Depletion of stratospheric ozone, resulting from atmospheric pollution has led to increased ultraviolet radiation at the earth’s surface as well as spectral shifts to the more biologically damaging shorter wavelengths. A decrease in the concentration of stratospheric ozone enhances the solar ultraviolet (UV) radiation, which is harmful to the growth of the plant and various other metabolic processes of the organisms and might cause changes in pigment concentrations, nucleic acids, and proteins. Multiple …


Estimating Methane Emissions From Biological And Fossil-Fuel Sources In The San Francisco Bay Area, Seongeun Jeong, Xinguang Cui, Donald Blake, Ben Miller, Stephen Montzka, Arlyn Andrews, Abhinav Guha, Philip Martien, Ray Bambha, Brian Lafranchi, Hope Michelsen, Craig Clements, Pierre Glaize, Marc Fischer Jan 2017

Estimating Methane Emissions From Biological And Fossil-Fuel Sources In The San Francisco Bay Area, Seongeun Jeong, Xinguang Cui, Donald Blake, Ben Miller, Stephen Montzka, Arlyn Andrews, Abhinav Guha, Philip Martien, Ray Bambha, Brian Lafranchi, Hope Michelsen, Craig Clements, Pierre Glaize, Marc Fischer

Faculty Publications, Meteorology and Climate Science

We present the first sector-specific analysis of methane (CH4) emissions from the San Francisco Bay Area (SFBA) using CH4 and volatile organic compound (VOC) measurements from six sites during September – December 2015. We apply a hierarchical Bayesian inversion to separate the biological from fossil-fuel (natural gas and petroleum) sources using the measurements of CH4 and selected VOCs, a source-specific 1 km CH4 emission model, and an atmospheric transport model. We estimate that SFBA CH4 emissions are 166–289 Gg CH4/yr (at 95% confidence), 1.3–2.3 times higher than a recent inventory with much of the underestimation from landfill. Including the VOCs, …


The Irreversible Momentum Of Clean Energy, Barack Obama Jan 2017

The Irreversible Momentum Of Clean Energy, Barack Obama

United States Department of Energy: Publications

The release of carbon dioxide (CO2) and other greenhouse gases (GHGs) due to human activity is increasing global average surface air temperatures, disrupting weather patterns, and acidifying the ocean. Left unchecked, the continued growth of GHG emissions could cause global average temperatures to increase by another 4°C or more by 2100 and by 1.5 to 2 times as much in many midcontinent and far northern locations. Although our understanding of the impacts of climate change is increasingly and disturbingly clear, there is still debate about the proper course for U.S. policy—a debate that is very much on display …


Implications Of Sea Ice On Southern Ocean Microseisms Detected By A Seismic Array In West Antarctica, Martin J. Pratt, Douglas A. Wiens, J. Paul Winberry, Sridhar Anandakrishnan, Garrett G. Euler Jan 2017

Implications Of Sea Ice On Southern Ocean Microseisms Detected By A Seismic Array In West Antarctica, Martin J. Pratt, Douglas A. Wiens, J. Paul Winberry, Sridhar Anandakrishnan, Garrett G. Euler

All Faculty Scholarship for the College of the Sciences

The proximity of Southern Ocean storms coupled with seasonal variation in sea ice make Antarctica ideal for the study of microseism sources. We explore frequency-dependent beamforming results using a short-duration, 60 km aperture, broad-band seismic array located on the Whillans Ice Stream, West Antarctica. Locations of single-frequency microseism (13–16 s period) generation are in regions where the continental shelf is ice-free, consistent with previous studies, and show Rayleigh wave sources remaining at consistent backazimuths throughout the duration of the array. Beamforming analysis of daily noise correlations shows that long-period double-frequency microseisms (9–11 s) consist predominantly of Rayleigh waves excited by …


Application Of Recurrent Neural Networks For Drought Projections In California, J. A. Le, Hesham El-Askary, Mohamed Allali, Daniele C. Struppa Jan 2017

Application Of Recurrent Neural Networks For Drought Projections In California, J. A. Le, Hesham El-Askary, Mohamed Allali, Daniele C. Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

We use recurrent neural networks (RNNs) to investigate the complex interactions between the long-term trend in dryness and a projected, short but intense, period of wetness due to the 2015-2016 El Niño. Although it was forecasted that this El Niño season would bring significant rainfall to the region, our long-term projections of the Palmer Z Index (PZI) showed a continuing drought trend, contrasting with the 1998-1999 El Niño event. RNN training considered PZI data during 1896-2006 that was validated against the 2006-2015 period to evaluate the potential of extreme precipitation forecast. We achieved a statistically significant correlation of 0.610 between …


The Gettysburg Economic Review, Volume 10, Spring 2017 Jan 2017

The Gettysburg Economic Review, Volume 10, Spring 2017

Gettysburg Economic Review

No abstract provided.