Climate Commons^™

Dynamical Downscaling Projections Of Late 21st Century U.S. Landfalling Hurricane Activity, Thomas R. Knutson, Joseph J. Sirutis, Morris A. Bender, Robert E. Tuleya

CCPO Publications

U.S. landfalling tropical cyclone (TC) activity was projected for late 21st century conditions using a two-step dynamical downscaling framework. A regional atmospheric model, run for 27 seasons, generated tropical storm cases. Each storm case was re-simulated (up to 15 days) using the higher resolution GFDL hurricane model. Thirteen CMIP3 or CMIP5 modeled climate change projections were explored as scenarios. Robustness of projections was assessed using statistical significance tests and comparing the sign of changes derived from different models. The proportion of TCs (tropical storms and hurricanes) making U.S. landfall increases for the warming scenarios (by order 50% or more). For …

Droughtscape, Winter 2021, National Drought Mitigation Center

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

DroughtScape, Winter 2021

Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby

Biological Sciences Faculty Publications

Ocean acidification (OA) is negatively affecting calcification in a wide variety of marine organisms. These effects are acute for many tropical scleractinian corals under short-term experimental conditions, but it is unclear how these effects interact with ecological processes, such as competition for space, to impact coral communities over multiple years. This study sought to test the use of individual-based models (IBMs) as a tool to scale up the effects of OA recorded in short-term studies to community-scale impacts, combining data from field surveys and mesocosm experiments to parameterize an IBM of coral community recovery on the fore reef of Moorea, …

Fast And Pervasive Transcriptomic Resilience And Acclimation Of Extremely Heat-Tolerant Coral Holobionts From The Northern Red Sea, Romain Savary, Daniel J. Barshis, Christian R. Voolstra, Anny Cárdenas, Nicolas R. Evensen, Guilhem Banc-Prandi, Maoz Fine, Anders Meiborn

Biological Sciences Faculty Publications

Corals from the northern Red Sea and Gulf of Aqaba exhibit extreme thermal tolerance. To examine the underlying gene expression dynamics, we exposed Stylophora pistillata from the Gulf of Aqaba to short-term (hours) and long-term (weeks) heat stress with peak seawater temperatures ranging from their maximum monthly mean of 27 °C (baseline) to 29.5 °C, 32 °C, and 34.5 °C. Corals were sampled at the end of the heat stress as well as after a recovery period at baseline temperature. Changes in coral host and symbiotic algal gene expression were determined via RNA-sequencing (RNA-Seq). Shifts in coral microbiome composition were …

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 …

Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan

Biological Sciences Faculty Publications

Phenotypic plasticity is one mechanism whereby species may cope with stressful environmental changes associated with climate change. Reef building corals present a good model for studying phenotypic plasticity because they have experienced rapid climate-driven declines in recent decades (within a single generation of many corals), often with differential survival among individuals during heat stress. Underlying differences in thermotolerance may be driven by differences in baseline levels of environmental stress, including pollution stress. To examine this possibility, acute heat stress experiments were conducted on Acropora hyacinthus from 10 sites around Tutuila, American Samoa with differing nutrient pollution impact. A threshold-based heat …

Predicting The Impacts Of Climate Change On The Great Lakes Water Levels Using A Fully Coupled 3d Regional Modeling System, Miraj Kayastha

Dissertations, Master's Theses and Master's Reports

The Great Lakes of North America are the largest surface freshwater system in the world and many ecosystems, industries, and coastal processes are sensitive to the changes in their water levels. The recent changes in the Great Lakes climate and water levels have particularly highlighted the importance of water level prediction. The water levels of the Great Lakes are primarily governed by the net basin supplies (NBS) of each lake which are the sum of over-lake precipitation and basin runoff minus lake evaporation. Recent studies have utilized Regional Climate Models (RCMs) with a fully coupled one-dimensional (1D) lake model to …

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 …

Eddy-Driven Transport Of Particulate Organic Carbon-Rich Coastal Water Off The West Antarctic Peninsula, Renato M. Castelao, Michael S. Dinniman, Caitlin M. Amos, John M. Klinck, Patricia M. Medeiros

CCPO Publications

The Southern Ocean is characterized by high eddy activity and high particulate organic carbon (POC) content during summer, especially near Antarctica. Because it encircles the globe, it provides a pathway for inter‐basin exchange. Here, we use satellite observations and a high‐resolution ocean model to quantify offshore transport of coastal water rich in POC off the West Antarctic Peninsula. We show that nonlinear cyclonic eddies generated near the coast often trap coastal water rich in POC during formation before propagating offshore. As a result, cyclones found offshore that were generated near the coast have on average higher POC content in their …

Riverine Carbon Cycling Over The Past Century In The Mid‐Atlantic Region Of The United States, Yuanzi Yao, Hanqin Tian, Shufen Pan, Raymond G. Najjar, Marjorie A.M. Friedrichs, Zihao Bian, Hong-Yi Li, Eileen E. Hofmann

CCPO Publications

The lateral transport and degassing of carbon in riverine ecosystems is difficult to quantify on large spatial and long temporal scales due to the relatively poor representation of carbon processes in many models. Here, we coupled a scale‐adaptive hydrological model with the Dynamic Land Ecosystem Model to simulate key riverine carbon processes across the Chesapeake and Delaware Bay Watersheds from 1900 to 2015. Our results suggest that throughout this time period riverine CO₂ degassing and lateral dissolved inorganic carbon fluxes to the coastal ocean contribute nearly equally to the total riverine carbon outputs (mean ± standard deviation: 886 ± …

Impacts Of Multiple Environmental Changes On Long‐Term Nitrogen Loading From The Chesapeake Bay Watershed, Shufen Pan, Zihao Bian, Hanqin Tian, Yuanzhi Yao, Raymond G. Najjar, Marjorie A.M. Friedrichs, Eileen E. Hofmann, Rongting Xu, Bowen Zhang

CCPO Publications

Excessive nutrient inputs from land, particularly nitrogen (N), have been found to increase the occurrence of hypoxia and harmful algal blooms in coastal ecosystems. To identify the main contributors of increased N loading and evaluate the efficacy of water pollution control policies, it is essential to quantify and attribute the long‐term changes in riverine N export. Here, we use a state‐of‐the‐art terrestrial–aquatic interface model to examine how multiple environmental factors may have affected N export from the Chesapeake Bay watershed since 1900. These factors include changes in climate, carbon dioxide, land use, and N inputs (i.e., atmospheric N deposition, animal …

Global Connectivity Of Southern Ocean Ecosystems, Eugene J. Murphy, Nadine M. Johnston, Eileen E. Hofmann, Richard A. Phillips, Jennifer A. Jackson, Andrew J. Constable, Sian F. Henley, Jessica Melbourne-Thomas, Rowan Trebilco, Rachel D. Cavanagh, Geraint A. Tarling, Ryan A. Saunders, David K.A. Barnes, Daniel P. Costa, Stuart P. Corney, Ceridwen I. Fraser, Juan Höfer, Kevin A. Hughes, Chester J. Sands, Sally E. Thorpe, Philip N. Trathan, José C. Xavier

CCPO Publications

Southern Ocean ecosystems are globally important. Processes in the Antarctic atmosphere, cryosphere, and the Southern Ocean directly influence global atmospheric and oceanic systems. Southern Ocean biogeochemistry has also been shown to have global importance. In contrast, ocean ecological processes are often seen as largely separate from the rest of the global system. In this paper, we consider the degree of ecological connectivity at different trophic levels, linking Southern Ocean ecosystems with the global ocean, and their importance not only for the regional ecosystem but also the wider Earth system. We also consider the human system connections, including the role of …

Measuring Winds From Space To Reduce The Uncertainty In The Southern Ocean Carbon Fluxes: Science Requirements And Proposed Mission, Joellen L. Russell, David G. Long, Paul Chang, Madeline Cowell, Enrique Curchitser, Michael S. Dinniman, Charles Fellows, Paul Goodman, Eileen Hofmann, Zorana Jelenak, John Klinck, John P. Krasting, Nicole Suzanne Lovenduski, Marcus Lofverstrom, Matthew R. Mazloff, Shelley Petroy, Anjani Polit, Ernesto Rodriguez, Oscar Schofield, Ad Stoffelen, Ronald J. Stouffer, Rik Wanninkhof, Carl Weimer, Xubin Zeng

CCPO Publications

Strong winds in Southern Ocean storms drive air-sea carbon and heat fluxes. These fluxes are integral to the global climate system and the wind speeds that drive them are increasing. The current scatterometer constellation measuring vector winds remotely undersamples these storms and the higher winds within them, leading to potentially large biases in Southern Ocean wind reanalyses and the fluxes that derive from them. This observing system design study addresses these issues in two ways. First, we describe an addition to the scatterometer constellation, called Southern Ocean Storms -- Zephyr, to increase the frequency of independent observations, better constraining high …

Coral Oxygen Isotopic Records Capture The 2015/2016 El Niño Event In The Central Equatorial Pacific, Gemma K. O'Connor, Kim M. Cobb, Hussein R. Sayani, Alyssa R. Atwood, Pamela R. Grothe, Samantha Stevenson, Et. Al.

Earth and Environmental Sciences

Coral oxygen isotopes (δ18O) from the central equatorial Pacific provide monthly resolved records of El Niño-Southern Oscillation activity over past centuries to millennia. However, calibration studies using in situ data to assess the relative contributions of warming and freshening to coral δ18O records are exceedingly rare. Furthermore, the fidelity of coral δ18O records under the most severe thermal stress events is difficult to assess. Here, we present six coral δ18O records and in situ temperature, salinity, and seawater δ18O data from Kiritimati Island (2°N, 157°W) spanning the very strong 2015/16 El Niño event. Local sea surface temperature (SST) anomalies of …

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 …

Can Stable Isotopes From Tree Rings Improve Our Understanding Of Past Variability In The Southern Annular Mode?, Zachary Grzywacz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Few annually dated stable isotope records exist across Oceania. In mid- to high-latitude locations in South America, tree-ring stable isotopes provide information about past climate dynamics such as the Southern Annular Mode (SAM). The SAM drives latitudinal shifts in Southern Hemisphere westerly winds, influencing temperature and moisture delivery across the mid- to high-latitudes, including Tasmania. Combinations of paleoclimate proxies from across the Southern Ocean might provide insight into dynamic processes like the SAM that are difficult to measure with a single proxy. Measuring stable carbon and oxygen isotope ratios from tree rings in Tasmania could provide complementary data to contribute …

Time Lags: Insights From The U.S. Long Term Ecological Research Network, Edward B. Rastetter, Mark D. Ohman, Katherine J. Elliott, J. S. Rehage, Victor H. Rivera-Monroy, R. E. Boucek, Edward Castañeda-Moya, Tess M. Danielson, Laura Gough, Peter M. Groffman, C. Rhett Jackson, Chelcy Ford Miniat, Gaius R. Shaver

Advanced Science Research Center

Ecosystems across the United States are changing in complex ways that are difficult to predict. Coordinated long-term research and analysis are required to assess how these changes will affect a diverse array of ecosystem services. This paper is part of a series that is a product of a synthesis effort of the U.S. National Science Foundation’s Long Term Ecological Research (LTER) network. This effort revealed that each LTER site had at least one compelling scientific case study about “what their site would look like” in 50 or 100 yr. As the site results were prepared, themes emerged, and the case …

Changes In The Philippine Coastal Environment, Karl H. Szekielda, Ma. Aileen Leah G. Guzman

Environmental Science Faculty Publications

Global warming is progressing at a faster speed than has been estimated earlier in climate forecasting, and the ocean responds rather quickly to global temperature increase. This study uses remotely sensed data that were accessed from the System for Multidisciplinary Research and Applications (NASA Giovanni) to study environmental change in the Philippines’ coast. Monthly averaged sea surface temperature series from around the Philippines indicate that the Philippines follow the global trend in ocean temperature increase and show the increase of about 0.50C within two decades. Despite the high variability in temperature, the linear regressions displayed for all seasons show an …

Experiential Learning In Soil Science: Evaluating Soil Quality In South Wollo, Ethiopia, Melissa Allen, Martha Mamo, Shimelis Beyene, Teshome Regassa, Gandura O. Abagandura, Solomon Abreha, Anthony James Mucia, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

This study abroad program provided an opportunity to enhance the international experience and research skills of University of Nebraska-Lincoln (UNL) students within a multidisciplinary team’s research-education goal on improving food security in Ethiopia. The experiential study component of the project included preparatory sessions during the Fall 2015 Semester at the UNL followed by a four- to five-week fieldwork experience in Ethiopia. Teams from the UNL and an Ethiopian university participated in survey data collection and field soil evaluations from farms in the Gerado area of South Wollo, Ethiopia. Having students interact with farmers increased student self-confidence and enhanced their leadership …

The Rise And Fall Of Wiñaymarka: Rethinking Cultural And Environmental Interactions In The Southern Basin Of Lake Titicaca, Maria C. Bruno, José M. Capriles, Christine A. Hastorf, Sherilyn C. Fritz, D. Marie Weide, Alejandra I. Domic, Paul A. Baker

Department of Earth and Atmospheric Sciences: Faculty Publications

Investigations of how past human societies managed during times of major climate change can inform our understanding of potential human responses to ongoing environmental change. In this study, we evaluate the impact of environmental variation on human communities over the last four millennia in the southern Lake Titicaca basin of the Andes, known as Lake Wiñaymarka. Refined paleoenvironmental reconstructions from new diatom-based reconstructions of lake level together with archaeological evidence of animal and plant resource use from sites on the Taraco Peninsula, Bolivia, reveal frequent climate and lake-level changes within major cultural phases. We posit that climate fluctuations alone do …

Inference Of Surface Velocities From Oblique Time Lapse Photos And Terrestrial Based Lidar At The Helheim Glacier, Franklyn T. Dunbar Ii

Graduate Student Theses, Dissertations, & Professional Papers

Using time dependent observations derived from terrestrial LiDAR and oblique
time-lapse imagery, we demonstrate that a Bayesian approach to glacial motion es-
timation provides a concise way to incorporate multiple data products into a single
motion estimation procedure effectively producing surface velocity estimates with
an associated uncertainty. This approach brings both improved computational effi-
ciency, and greater scalability across observational time-frames when compared to
existing methods. To gauge efficacy, we apply these methods to a set of observa-
tions from the Helheim Glacier, a critical actor in contemporary mass loss trends
observed in the Greenland Ice Sheet. We find that …

Recent Flooding Events On The Chagrin And Cuyahoga Rivers, Ohio, Kayley Martin

Williams Honors College, Honors Research Projects

From the 1910s through the 1980s, the number of intense daily precipitation events in the United States remained constant, however, since the 1980s there has been an increasing trend in intense single-day precipitation events (U.S Environmental Protection Agency, 2016). One outcome of intense precipitation events is river flooding, particularly in the upper Midwest region where floods have increased in magnitude and frequency (U.S Environmental Protection Agency, 2016). In this thesis project, recent flooding history on the Chagrin and Cuyahoga Rivers in Ohio was studied to expand on previous research that observed an abrupt increase in high magnitude flood events on …

Temperature Variance Portends And Indicates The Extent Of Abrupt Climate Shifts, Christine Ramadhin, Chuixiang Yi, George Hendrey

Publications and Research

Here, we show a discernable increase in temperature variance before a glacial termination by both the Ansari-Bradley test and the moving variance methods plus introduce the idea that there is a correlation between the peak variance and peak temperature increase. The behavior of temperature variance shows potential as a useful tool in analyzing time series data of Earth systems to assess the risk and extent of an upcoming abrupt climate transition.

Particle Identification Of Pyro-Convection From Wildfires, Justin Province

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

No abstract provided.

Plant Physiological Responses To Environmental Change In A Marsh-Mangrove Ecotone, Matthew Sturchio

UNF Graduate Theses and Dissertations

Globally, photosynthesis (A) and autotrophic respiration (R) are the two largest physiological processes responsible for CO₂ flux. Coastal wetland ecosystems are responsible for some of the highest rates of C sequestration. Marsh grass and mangrove habitats responsible for this service are important in supporting biodiversity and preventing shoreline erosion, yet little is known about how this vegetation will respond physiologically to effects of climate and global change. In the first chapter a warming experiment was used to determine whether a C₄ marsh grass (Spartina alterniflora) and a C₃ mangrove (Avicennia …

Wave Climate Associated With Changing Water Level And Ice Cover In Lake Michigan, Chenfu Huang, Longhuan Zhu, Gangfeng Ma, Guy A. Meadows, Pengfei Xue

Civil & Environmental Engineering Faculty Publications

Detailed knowledge of wave climate change is essential for understanding coastal geomorphological processes, ecosystem resilience, the design of offshore and coastal engineering structures and aquaculture systems. In Lake Michigan, the in-situ wave observations suitable for long-term analysis are limited to two offshore MetOcean buoys. Since this distribution is inadequate to fully represent spatial patterns of wave climate across the lake, a series of high-resolution SWAN model simulations were performed for the analysis of long-term wave climate change for the entirety of Lake Michigan from 1979 to 2020. Model results were validated against observations from two offshore buoys and 16 coastal …

Characterizing Seagrass Effects On Hydrodynamics Of Waves And Currents Through Field Measurements And Computational Modelling, Ramin Familkhalili, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

Low-lying coastal and estuarine areas are among the most populated regions globally, have high economic significance, and are increasingly threatened by climate change, sea level rise, nuisance flooding, and extreme storms. Nature-based coastal protections are sustainable and sea-level resilient alternatives compared to traditional solutions such as dikes and seawalls. Submerged aquatic vegetation (SAV) or seagrasses can provide coastal flood and erosion protection by attenuating storm wave and current energy and stabilizing seabed sediments. However, more research is needed to understand the interactions between flow, SAVs, and sediments. These dynamic interactions affect flow at different scales and seagrass productivity. In this …

Effects Of Hydrological And Climatic Variables On Cyanobacterial Blooms In Four Large Shallow Lakes Fed By The Yangtze River, Jian Huang, Qiujin Xu, Xixi Wang, Hao Ji, Edward J. Quigley, Mohamadali Sharbatmaleki, Simeng Li, Beidou Xi, Biao Sun, Caole Li

Civil & Environmental Engineering Faculty Publications

Shallow lakes, one of the most widespread water bodies in the world, are easily shifted to a new trophic state due to external interferences. Shifting hydrologic conditions and climate change can cause cyanobacterial harmful algal blooms (CyanoHABs) in shallow lakes, which pose serious threats to ecological integrity and human health. This study analyzed the effects of hydrologic and meteorological variables on cyanobacterial blooms in Yangtze-connected lakes (Lake Dongting and Poyang) and isolated lakes (Lake Chao and Tai). The results show that (i) chlorophyll-a (Chl-a) concentration tends to decrease exponentially with increasing relative lake level fluctuations (RLLF) and precipitation, but to …

Quantification Of Climate Variability And Extreme Events In The Great Plains, Angelinah Ntsieng Rasoeu

Electronic Theses and Dissertations

Climate variability and extreme events continue to worsen resulting in significant impacts to society and the environment. Quantifying precipitation variability, streamflow, and extreme events at local scale is crucial for local planning and management due to spatial and temporal precipitation variability which influences streamflow and thus, water resources. This study uses statistical tools to analyze 1895-2019 (125 years) of historical precipitation data to examine how long-term precipitation varies annually, seasonally, and monthly, and create climate classifications. The results show that annual precipitation is increasing linearly over time ranging from 13.2 in (1976) to 43.1 in (2010) and 5 climate classes …

Pattern-Based Downscaling Of Snowpack Variability In The Western United States, Nicolas Gauthier, Kevin J. Anchukaitis, Bethany Coulthard

Geoscience Faculty Research

The decline in snowpack across the western United States is one of the most pressing threats posed by climate change to regional economies and livelihoods. Earth system models are important tools for exploring past and future snowpack variability, yet their coarse spatial resolutions distort local topography and bias spatial patterns of accumulation and ablation. Here, we explore pattern-based statistical downscaling for spatially-continuous interannual snowpack estimates. We find that a few leading patterns capture the majority of snowpack variability across the western US in observations, reanalyses, and free-running simulations. Pattern-based downscaling methods yield accurate, high resolution maps that correct mean and …