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Physical Sciences and Mathematics

2016

Climate change

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Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson Dec 2016

Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson

Biology ETDs

The Southwestern US is predicted to become hotter and drier, as global climate change forces increasing temperatures and variability in timing and size of precipitation inputs. Drought stress has become more frequent in recent decades, and resulted in massive forest mortality in piñon-juniper woodlands. During recent severe droughts (2000-2003, 2009-2012), piñon pine (Pinus edulis Englem.) suffered disproportionately high mortality compared to co-occurring one-seed juniper (Juniperus monosperma [Engelm.] Sarg.). A large-scale precipitation manipulation experiment was established in a piñon-juniper woodland in central New Mexico to test hypotheses regarding tree survival and mortality with respect to altered water regimes. Our …


Effects Of Temperature On Activity Of Aquatic Hyphomycetes: A Microcosm Study, Kyra Harrington‌‌ Dec 2016

Effects Of Temperature On Activity Of Aquatic Hyphomycetes: A Microcosm Study, Kyra Harrington‌‌

Honors Theses

Predicted increases in temperature under climate change scenarios are expected to affect not only atmospheric and water temperatures, but also the rate of heterotrophic activity and carbon dynamics and retention in ecosystems. The magnitude of the increase in metabolic activity of living organisms with increased temperature can be predicted by the Metabolic Theory of Ecology, however, multiple factors can cause deviations from simple predictions. The goal of this study is to assess the temperature sensitivity of aquatic hyphomycetes and fungi-mediated leaf litter decomposition by following responses to temperature of fungal biomass accrual, respiration and decomposition rates in laboratory microcosms simulating …


Sea Surface Temperature Rises Shift Migration Patterns Due To Ecosystem Changes, Alexia Skrbic, Hesham El-Askary Dec 2016

Sea Surface Temperature Rises Shift Migration Patterns Due To Ecosystem Changes, Alexia Skrbic, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

The continuing climate change is negatively impacting ecosystems, specifically oceans which are declining and food webs are being altered by the increase of greenhouse gases. The increase of the carbon dioxide and other greenhouse gases is increasing sea surface temperature of the world’s oceans. Certain organisms lower on the food chain like phytoplankton and zooplankton are directly affected by the warming which alters how they process nutrients and their productivity. The limited amount of these primary producers in the oceans and specifically the location they inhabit directly affects all the organisms above them on the food chain. Several marine animals …


Reducing Emissions From Agriculture To Meet The 2 °C Target, Eva Wollenberg, Meryl Richards, Pete Smith, Petr Havlík, Michael Obersteiner, Francesco N. Tubiello, Martin Herold, Pierre Gerber, Sarah Carter, Andrew Reisinger, Detlef P. Van Vuuren, Amy Dickie, Henry Neufeldt, Björn O. Sander, Reiner Wassmann, Rolf Sommer, James E. Amonette, Alessandra Falcucci, Mario Herrero, Carolyn Opio, Rosa Maria Roman-Cuesta, Elke Stehfest, Henk Westhoek, Ivan Ortiz-Monasterio, Tek Sapkota, Mariana C. Rufino, Philip K. Thornton, Louis Verchot, Paul C. West, Jean François Soussana, Tobias Baedeker Dec 2016

Reducing Emissions From Agriculture To Meet The 2 °C Target, Eva Wollenberg, Meryl Richards, Pete Smith, Petr Havlík, Michael Obersteiner, Francesco N. Tubiello, Martin Herold, Pierre Gerber, Sarah Carter, Andrew Reisinger, Detlef P. Van Vuuren, Amy Dickie, Henry Neufeldt, Björn O. Sander, Reiner Wassmann, Rolf Sommer, James E. Amonette, Alessandra Falcucci, Mario Herrero, Carolyn Opio, Rosa Maria Roman-Cuesta, Elke Stehfest, Henk Westhoek, Ivan Ortiz-Monasterio, Tek Sapkota, Mariana C. Rufino, Philip K. Thornton, Louis Verchot, Paul C. West, Jean François Soussana, Tobias Baedeker

Rubenstein School of Environment and Natural Resources Faculty Publications

More than 100 countries pledged to reduce agricultural greenhouse gas (GHG) emissions in the 2015 Paris Agreement of the United Nations Framework Convention on Climate Change. Yet technical information about how much mitigation is needed in the sector vs. how much is feasible remains poor. We identify a preliminary global target for reducing emissions from agriculture of ~1 GtCO2e yr−1 by 2030 to limit warming in 2100 to 2 °C above pre-industrial levels. Yet plausible agricultural development pathways with mitigation cobenefits deliver only 21–40% of needed mitigation. The target indicates that more transformative technical and policy options will be needed, …


Exploring The Potential Impacts Of Climate Change On North America's Laurentian Great Lakes Tourism Sector, Natalie Chin Dec 2016

Exploring The Potential Impacts Of Climate Change On North America's Laurentian Great Lakes Tourism Sector, Natalie Chin

Open Access Dissertations

Climate change is one of the major challenges facing the global hospitality and tourism sector in the coming century and, given the important role that weather and climate play in all aspects of the tourism experience, tourism businesses owners need to start thinking about and enacting climate change adaptation strategies now. This work has utilized a combination of social science and physical science methods to (1) understand how the Great Lakes tourism sector could be impacted by climate change and (2) provide some insights into how researchers can help business owners prepare for these potential impacts. Overall, the results of …


Seasonal Glacial Meltwater Contributions To Surface Water In The Bolivian Andes: A Case Study Using Environmental Tracers, Zack Guido, Jennifer C. Mcintosh, Shirley A. Papuga, Thomas Meixner Oct 2016

Seasonal Glacial Meltwater Contributions To Surface Water In The Bolivian Andes: A Case Study Using Environmental Tracers, Zack Guido, Jennifer C. Mcintosh, Shirley A. Papuga, Thomas Meixner

Environmental Science and Geology Faculty Research Publications

Study region: The Cordoriri watershed and vicinity in the Cordillera Real, Bolivia, South America

Study focus: Recent warming has contributed to substantial reductions in glaciers in many regions around the globe. Melting of these glaciers alters the timing and magnitude of stream flows and diminishes water resources accumulated in past climates. These changes are especially acute in regions with small glaciers and problematic for populations relying on surface water. In Bolivia, most glaciers are less than 0.5 km2 and about 2 million people draw water in part from glacier-fed watersheds. Sparse monitoring, however, has limited estimates of …


Agenda: Winter, Wilderness & Climate: Threats & Solutions, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment, The Wilderness Society, Protect Our Winters Oct 2016

Agenda: Winter, Wilderness & Climate: Threats & Solutions, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment, The Wilderness Society, Protect Our Winters

Winter, Wilderness, and Climate--Threats and Solutions (October 12)

In partnership with the Getches-Wilkinson Center, join The Wilderness Society and Protect Our Winters for an interactive presentation about energy development and climate impacts on public lands.

This event was held on Wednesday, October 12, 2016, 5:30 - 7:30 p.m., in the University of Colorado Law School, Wolf Law Building, Wittemyer Courtroom.


Slides: Winter, Wilderness & Climate: Threats & Solutions, Jim Ramey, Lindsay Bourgoine Oct 2016

Slides: Winter, Wilderness & Climate: Threats & Solutions, Jim Ramey, Lindsay Bourgoine

Winter, Wilderness, and Climate--Threats and Solutions (October 12)

Presenters:

Jim Ramey, The Wilderness Society

Lindsay Bourgoine, Protect Our Winters

56 slides


Biophysical And Hydrological Effects Of Future Climate Change Including Trends In Co2, In The St. Joseph River Watershed, Eastern Corn Belt, Ruoyu Wang Sep 2016

Biophysical And Hydrological Effects Of Future Climate Change Including Trends In Co2, In The St. Joseph River Watershed, Eastern Corn Belt, Ruoyu Wang

Ruoyu Wang

Future climate change has the potential to significantly impact crop growth, both directly due to CO2 enhancement and indirectly, through temperature and moisture impacts. This work investigates the biophysical and hydrological effects of future climate change, including trends in CO2, in the St. Joseph River watershed, Eastern Corn Belt. In this study, the Soil and Water Assessment Tool (SWAT) was first modified to take dynamic CO2 concentration as input. A regional crop leaf development curve from Landsat TM imagery was also used to adjust model performance in corn leaf area development for the historical period. A multi-objective calibration strategy was …


Century-Long Increasing Trend And Variability Of Dissolved Organic Carbon Export From The Mississippi River Basin Driven By Natural And Anthropogenic Forcing, Wei Ren, Hanqin Tian, Wei-Jun Cai, Steven E. Lohrenz, Charles S. Hopkinson, Wei-Jen Huang, Jia Yang, Bo Tao, Shufen Pan, Ruoying He Sep 2016

Century-Long Increasing Trend And Variability Of Dissolved Organic Carbon Export From The Mississippi River Basin Driven By Natural And Anthropogenic Forcing, Wei Ren, Hanqin Tian, Wei-Jun Cai, Steven E. Lohrenz, Charles S. Hopkinson, Wei-Jen Huang, Jia Yang, Bo Tao, Shufen Pan, Ruoying He

Plant and Soil Sciences Faculty Publications

There has been considerable debate as to how natural forcing and anthropogenic activities alter the timing and magnitude of the delivery of dissolved organic carbon (DOC) to the coastal ocean, which has ramifications for the ocean carbon budget, land-ocean interactions, and coastal life. Here we present an analysis of DOC export from the Mississippi River to the Gulf of Mexico during 1901–2010 as influenced by changes in climate, land use and management practices, atmospheric CO2, and nitrogen deposition, through the integration of observational data with a coupled hydrologic/biogeochemical land model. Model simulations show that DOC export in the …


Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang Sep 2016

Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang

Xiaoyang Zhang

Climate influences geographic differences of vegetation phenology through both contemporary and historical variability. The latter effect is embodied in vegetation heterogeneity underlain by spatially varied genotype and species compositions tied to climatic adaptation. Such long-term climatic effects are difficult to map and therefore often neglected in evaluating spatially explicit phenological responses to climate change. In this study we demonstrate a way to indirectly infer the portion of land surface phenology variation that is potentially contributed by underlying genotypic differences across space. The method undertaken normalized remotely sensed vegetation start-of-season (or greenup onset) with a cloned plants-based phenological model. As the …


Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan Sep 2016

Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan

Plant and Soil Sciences Faculty Publications

Given the importance of the potential positive feedback between methane (CH4) emissions and climate change, it is critical to accurately estimate the magnitude and spatiotemporal patterns of CH4 emissions from global rice fields and better understand the underlying determinants governing the emissions. Here we used a coupled biogeochemical model in combination with satellite-derived contemporary inundation area to quantify the magnitude and spatiotemporal variation of CH4 emissions from global rice fields and attribute the environmental controls of CH4 emissions during 1901–2010. Our study estimated that CH4 emissions from global rice fields varied from 18.3 ± …


Using Photovoice To Understand Climate Change Adaptation In Rural Ontario, Kylie Hissa Sep 2016

Using Photovoice To Understand Climate Change Adaptation In Rural Ontario, Kylie Hissa

Geography and Environmental Studies Major Research Papers

The examination of community adaptation and resilience approaches to address the threats of climate change in rural Ontario is becoming increasingly important in emergency management and preparedness. Community engagement becomes critical in this regard, as local experiences partly influence perceptions of climate change risks within municipalities. Photovoice is a community-based participatory research methodology that empowers participants to document their perceptions and understandings of a particular issue through the use of visual images. This technique was undertaken to understand the impacts of the F3 tornado that hit the community of Goderich, Ontario in 2011 and capture their member’s perceptions on disaster …


Icelandic Fisheries: Scenario Planning For Climate Change, Tara Sorrels Sep 2016

Icelandic Fisheries: Scenario Planning For Climate Change, Tara Sorrels

Mahurin Honors College Capstone Experience/Thesis Projects

This study aimed to develop an understanding of how a scenario planning process could be used to assist businesses to adapt to climate change. The focus of this study was on the Icelandic fishing industry since Iceland is experiencing firsthand climate change impacts. Mitigation strategies are the main focus in climate change research, but this study focused on a possible adaptation method that requires changing management practices in order to reduce the impact of climate change on the economy. Tours of Icelandic fisheries and interviews with individuals within the Icelandic fishing industry were conducted to assess the current adaptive capacity …


The International Whaling Commission—Beyond Whaling, Andrew J. Wright, Mark P. Simmonds, Barbara Galletti Vernazzani Aug 2016

The International Whaling Commission—Beyond Whaling, Andrew J. Wright, Mark P. Simmonds, Barbara Galletti Vernazzani

Environment and Nature Conservation Collection

Since its establishment in 1946 as the international body intended to manage whaling, the International Whaling Commission (IWC) has expanded its areas of interest to ensure the wider conservation of whales. Several key conservation topics have been taken forward under its auspices including climate change, chemical and noise pollution, marine debris and whale watching. Work on each of these topics at the IWC has grown substantially since the 1990s and remains ongoing. Important developments were the establishment of the Standing Working Group on Environmental Concerns in 1996 and the IWC’s Conservation Committee in 2003. Trying to address this diverse set …


Climate Change Is The Reason We Need For Resiliency, Michael Allen Aug 2016

Climate Change Is The Reason We Need For Resiliency, Michael Allen

News Items

Guest editorial by Michael Allen concerning the draft of the Norfolk Vision 2100 by the Norfolk Planning Department.


Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez Aug 2016

Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez

Open Access Dissertations

Habitat replacement and fragmentation associated with projected climate change pose a critical threat to global biodiversity. Edaphically limited plant species with restricted dispersal abilities will be especially handicapped to track their optimal climate spatially. Instead, the persistence of these species will depend on their capacity to adapt in situ to novel climate regimes. Here I evaluated the evolutionary potential of Lasthenia fremontii, an annual plant species restricted to ephemeral wetlands called vernal pools in California to adapt to the projected patterns of climate change. Across L. fremontii distribution there is a latitudinal gradient in precipitation which, combined with reduced …


The Impact Of Climate Change In Bangladesh On The Rice Market And Farm Households, Mst Ashrafun Nahar Aug 2016

The Impact Of Climate Change In Bangladesh On The Rice Market And Farm Households, Mst Ashrafun Nahar

Graduate Theses and Dissertations

Bangladesh is trying to achieve self-sufficiency in domestic rice production but climate change effects on agricultural production makes it challenging to attain the goal. The country is highly vulnerable to the effects of climate change since it is the major cause to rise in sea level, more warm summer, and happening food and cyclone in the country.

This study develops an Aggregate Farm Household Model to analyze the impact of potential land loss and yield reduction from climate change on production, consumption, prices, welfare, and the ability of government to achieve self-sufficiency in rice production. The model is calibrated to …


Electricity Generation, Electricity Consumption, And Energy Efficiency In The United States: A Dual Climatic-Behavioral Approach, Christopher A. Craig Aug 2016

Electricity Generation, Electricity Consumption, And Energy Efficiency In The United States: A Dual Climatic-Behavioral Approach, Christopher A. Craig

Graduate Theses and Dissertations

Much of the United States (US) has seen an increase in warm days, decrease in cool days, and increase in extreme weather events. These trends are projected to continue across much of the US and in turn increase the demand for electricity and subsequent greenhouse gas emissions. Ambitious energy efficiency (EE) programs are used across the US by energy utility organizations to reduce electricity demand and emissions. This study examined the impact of climatic variability on electricity consumption, as well as how pro-conservation interventions such as EE programs and experiential learning can be utilized to mitigate residential electricity consumption and …


Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu Aug 2016

Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu

Graduate Theses and Dissertations

Although climate change impacts vary geographically and temporally, studies at local levels are not readily available for stakeholders to better understand how their local communities would be affected and what remedial measures could be more effective in their local contexts. This dissertation has examined climate change and its impacts in two different local contexts: eastern Arkansas in the USA and Nyando in Kenya. The first part of this dissertation develops agro-meteorological indicators and examines the relationship between agro-meteorological indicators and crop yields in eastern Arkansas between 1960 and 2014. Results reveal that temperature based indicators were more strongly correlated to …


The Science Of Sea Level Rise And The Impact Of The Gulf Stream, Tal Ezer Jul 2016

The Science Of Sea Level Rise And The Impact Of The Gulf Stream, Tal Ezer

July 29, 2016: The Latest in Sea Level Rise Science

No abstract provided.


Coral Persistence To Ocean Warming Via Developmental Acclimation, Heather L. Schaneen Jul 2016

Coral Persistence To Ocean Warming Via Developmental Acclimation, Heather L. Schaneen

HCNSO Student Theses and Dissertations

Scleractinian corals are the ‘engineers’ of tropical coral reef ecosystems. Their three-dimensional structure provides habitat for thousands of fish and invertebrate species. The persistence of corals is threatened by climate change. In this study I investigated if corals may be able to increase tolerance to ocean warming through developmental acclimation, i.e. if corals that experience warmer temperatures during embryonic and larval development are better able to cope with higher temperatures later in life. Larvae of the broadcast spawning coral Montastraea cavernosa were raised at ambient (29°C) and future projected ocean warming temperatures (+2°C, 31°C). After larval settlement, coral juveniles from …


Changing Sediment Transport Processes In Response To Anthropocene Forcing, Brian C. Yellen Jul 2016

Changing Sediment Transport Processes In Response To Anthropocene Forcing, Brian C. Yellen

Doctoral Dissertations

The denudation of uplands and sediment deposition within lowlands comprises one of the most fundamental earth processes. Much like plate tectonics or isostasy, sediment transport runs through nearly every geologic sub-discipline. Its importance extends to other fields as well, such as soil and plant science, archaeology, and engineering. Research in the field of sedimentology remains current, with changes in global sediment transport invoked as a primary line of evidence for the arrival of the Anthropocene, and sedimentary archives frequently employed to evaluate current processes relative to the past. In this vein, my doctoral studies have centered on understanding some aspects …


Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole Jul 2016

Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole

DePaul Discoveries

Isoprene, the most abundant hydrocarbon in the atmosphere, plays a significant role in atmospheric chemistry. Its reactions with NOx lead to the formation of ozone in the lower troposphere, which is harmful to plants and detrimental to human health. As air temperatures and CO2 concentrations increase with climate change, it is uncertain how isoprene emissions from plants will respond. We hypothesized that isoprene emissions will increase with the combination of increasing temperature and CO­2 concentrations. We predict that oaks grown at a higher temperature will exhibit an increase in isoprene emissions with combined short-term increases in temperature …


The Influence Of Model Resolution On The Simulated Sensitivity Of North Atlantic Tropical Cyclone Maximum Intensity To Sea Surface Temperature, Sarah Strazzo, James Elsner, Timothy Larow, Hiroyuki Murakami, Michael Wehner, Ming Zhao Jul 2016

The Influence Of Model Resolution On The Simulated Sensitivity Of North Atlantic Tropical Cyclone Maximum Intensity To Sea Surface Temperature, Sarah Strazzo, James Elsner, Timothy Larow, Hiroyuki Murakami, Michael Wehner, Ming Zhao

Publications

No abstract provided.


Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown Jul 2016

Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown

USF Tampa Graduate Theses and Dissertations

Climate change is arguably the greatest environmental and economic challenge of our time. There are considerable documented and projected impacts to both human and natural systems as a result of climate change. These impacts include changes in temperature, sea level, precipitation patterns, and biogeography of ecologically and economically relevant species, including pathogens. One of the main drivers of climate change is elevated levels of atmospheric carbon dioxide (CO2), a greenhouse gas. Since pre-industrial times, atmospheric CO2 levels have increased from approximately 280 ppm to over 400 ppm, as a result of fossil fuel combustion, cement production and …


Climate-Ready Agriculture: A Situation Statement For Western Australia, Robert Anthony Sudmeyer, Anne Bennett, Melanie Strawbridge Jul 2016

Climate-Ready Agriculture: A Situation Statement For Western Australia, Robert Anthony Sudmeyer, Anne Bennett, Melanie Strawbridge

Bulletins 4000 -

Projected future changes in the state’s climate will present new challenges for our producers. The Department of Agriculture and Food, Western Australia (DAFWA) continues to work with agricultural industries to lay solid foundations for an agricultural sector that has a range of response options.

This situation statement provides an assessment of how climate-ready the state’s agricultural sectors are and provides guidance for investment priorities for DAFWA for the period 2015–2020.


Linking In-Situ Data With Remote Sensing To Analyze Tropical Glacier Stability And Retreat In The Cordillera Blanca, Peru, Chandler H. Santos Jul 2016

Linking In-Situ Data With Remote Sensing To Analyze Tropical Glacier Stability And Retreat In The Cordillera Blanca, Peru, Chandler H. Santos

Masters Theses & Specialist Projects

Glaciers are a major source of freshwater around the world, but they are melting at an increased rate due to atmospheric warming resulting from anthropogenic climate change. In addition to temperature increases, light-absorbing particulates on glaciers also are contributing to glacial melt. This research examines how black carbon, released into the air through partial combustion of biofuels, is affecting the surface albedo of glaciers. I also delineate possible sources of black carbon in the Cordillera Blanca region of Peru. Ground data were collected each year from 2011 to 2013 during the local dry season. Effective black carbon (eBC) values were …


A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt Jun 2016

A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt

United States Geological Survey: Staff Publications

The effects of climate change have wide-ranging impacts on wildlife species and recent studies indicate that birds’ spring arrival dates are advancing in response to changes in global climates. In this paper, we propose a spatio-temporal approach for comparing avian first arrival data for multiple species. As an example, we analyze spring arrival data for two long-distance migrants (Rubythroated Hummingbird Archilochus colubris; and Purple Martin Progne subis) in eastern North America from 2001–2010 using Citizen Science data. The proposed approach provides researchers with a tool to compare mean arrival dates while accounting for spatial and temporal variability. Our results show …


Steinhilber Outlines Odu's Multidisciplinary Sea Level Rise Research At Virginia Beach Forum, Brendan O'Hallarn Jun 2016

Steinhilber Outlines Odu's Multidisciplinary Sea Level Rise Research At Virginia Beach Forum, Brendan O'Hallarn

News Items

No abstract provided.