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Full-Text Articles in Environmental Indicators and Impact Assessment

Multi-Dimensional Drought Assessment In Abbay/Upper Blue Nile Basin: The Importance Of Shared Management And Regional Coordination Efforts For Mitigation, Yared Bayissa, Semu Moges, Assefa Melesse, Tsegaye Tadesse, Anteneh Z. Abiy, Abeyou Worqlul May 2021

Multi-Dimensional Drought Assessment In Abbay/Upper Blue Nile Basin: The Importance Of Shared Management And Regional Coordination Efforts For Mitigation, Yared Bayissa, Semu Moges, Assefa Melesse, Tsegaye Tadesse, Anteneh Z. Abiy, Abeyou Worqlul

National Drought Mitigation Center: Faculty Publications

Drought is one of the least understood and complex natural hazards often characterized by a significant decrease in water availability for a prolonged period. It can be manifested in one or more forms as meteorological, agricultural, hydrological, and/or socio-economic drought. The overarching objective of this study is to demonstrate and characterize the different forms of droughts and to assess the multidimensional nature of drought in the Abbay/ Upper Blue Nile River (UBN) basin and its national and regional scale implications. In this study, multiple drought indices derived from in situ and earth observation-based hydro-climatic variables were used. The meteorological drought …


An Integrated Approach For The Assessment And Monitoring Of Land Deformation In The Riyadh City And Its Surroundings For Identifying The Controlling Factors, Abdulaziz Ibrahim Aljammaz May 2021

An Integrated Approach For The Assessment And Monitoring Of Land Deformation In The Riyadh City And Its Surroundings For Identifying The Controlling Factors, Abdulaziz Ibrahim Aljammaz

Dissertations

An integrated approach (remote sensing, field, geodesy, geology, and hydrogeology) was conducted to assess and monitor land deformation at Riyadh city and its surroundings. Two settings were investigated. The first, Jinadriyah area (1.5 km2), an urban area located east of Riyadh city, was selected to assess deformation associated with urbanization over desert lands. The second location was Al Kharj area (19,790 km2) to the south of Riyadh city, a reclaimed desert land that was selected to assess the deformation associated with agricultural groundwater extraction from fossil aquifers. My investigations revealed high subsidence rates (up to -30 …


Removal Of Carbamazepine Onto Modified Zeolitic Tuff In Different Water Matrices: Batch And Continuous Flow Experiments, Othman A. Al-Mashaqbeh, Diya A. Alsafadi, Layal Z. Alsalhi, Shannon L. Bartelt-Hunt, Daniel D. Snow Apr 2021

Removal Of Carbamazepine Onto Modified Zeolitic Tuff In Different Water Matrices: Batch And Continuous Flow Experiments, Othman A. Al-Mashaqbeh, Diya A. Alsafadi, Layal Z. Alsalhi, Shannon L. Bartelt-Hunt, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Carbamazepine (CBZ) is the most frequently detected pharmaceutical residues in aquatic environments effluent by wastewater treatment plants. Batch and column experiments were conducted to evaluate the removal of CBZ from ultra-pure water and wastewater treatment plant (WWTP) effluent using raw zeolitic tuff (RZT) and surfactant modified zeolite (SMZ). Point zero net charge (pHpzc), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier Transform Infrared (FTIR) were investigated for adsorbents to evaluate the physiochemical changes resulted from the modification process using Hexadecyltrimethylammonium bromide (HDTMA-Br). XRD and FTIR showed that the surfactant modification of RZT has created an amorphous surface with new alkyl …


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 …


Exploring Viirs Continuity With Modis In An Expedited Capability For Monitoring Drought-Related Vegetation Conditions, Trenton D. Benedict, Jesslyn F. Brown, Stephen P. Boyte, Daniel M. Howard, Brian A. Fuchs, Brian D. Wardlow, Tsegaye Tadesse, Kirk A. Evenson Mar 2021

Exploring Viirs Continuity With Modis In An Expedited Capability For Monitoring Drought-Related Vegetation Conditions, Trenton D. Benedict, Jesslyn F. Brown, Stephen P. Boyte, Daniel M. Howard, Brian A. Fuchs, Brian D. Wardlow, Tsegaye Tadesse, Kirk A. Evenson

National Drought Mitigation Center: Faculty Publications

Vegetation has been effectively monitored using remote sensing time-series vegetation index (VI) data for several decades. Drought monitoring has been a common application with algorithms tuned to capturing anomalous temporal and spatial vegetation patterns. Drought stress models, such as the Vegetation Drought Response Index (VegDRI), often use VIs like the Normalized Difference Vegetation Index (NDVI). The EROS expedited Moderate Resolution Imaging Spectrora-diometer (eMODIS)-based, 7-day NDVI composites are integral to the VegDRI. As MODIS satellite platforms (Terra and Aqua) approach mission end, the Visible Infrared Imaging Radiometer Suite (VIIRS) presents an alternate NDVI source, with daily collection, similar band passes, and …


Exploring Viirs Continuity With Modis In An Expedited Capability For Monitoring Drought-Related Vegetation Conditions, Trenton D. Benedict, Jesslyn F. Brown, Stephen P. Boyte, Daniel M. Howard, Brian A. Fuchs, Brian D. Wardlow, Tsegaye Tadesse, Kirk A. Evenson Mar 2021

Exploring Viirs Continuity With Modis In An Expedited Capability For Monitoring Drought-Related Vegetation Conditions, Trenton D. Benedict, Jesslyn F. Brown, Stephen P. Boyte, Daniel M. Howard, Brian A. Fuchs, Brian D. Wardlow, Tsegaye Tadesse, Kirk A. Evenson

National Drought Mitigation Center: Faculty Publications

Vegetation has been effectively monitored using remote sensing time-series vegetation index (VI) data for several decades. Drought monitoring has been a common application with algorithms tuned to capturing anomalous temporal and spatial vegetation patterns. Drought stress models, such as the Vegetation Drought Response Index (VegDRI), often use VIs like the Normalized Difference Vegetation Index (NDVI). The EROS expedited Moderate Resolution Imaging Spectrora-diometer (eMODIS)-based, 7-day NDVI composites are integral to the VegDRI. As MODIS satellite platforms (Terra and Aqua) approach mission end, the Visible Infrared Imaging Radiometer Suite (VIIRS) presents an alternate NDVI source, with daily collection, similar band passes, and …


The Drought Monitor Comes Of Age, Brad Rippey, Brian Fuchs, David Simeral, Deborah J. Bathke, Richard R. Heim Jr., Mark Svoboda Mar 2021

The Drought Monitor Comes Of Age, Brad Rippey, Brian Fuchs, David Simeral, Deborah J. Bathke, Richard R. Heim Jr., Mark Svoboda

National Drought Mitigation Center: Faculty Publications

The 20th century featured immense scientific discoveries and advances. Astrophysics gained Einstein’s life-altering theory of relativity, opening the door to nuclear weaponry and the mind-bending Big Bang theory. The medical field achieved stunning success in suppressing or vanquishing a host of deadly diseases, including polio and smallpox. And through advances in computing technology, meteorological forecasting moved from back-of-the-envelope calculations to supercomputers. However, drought monitoring fell behind the curve of scientific advancement. Not until 1965, when the United States Department of Commerce published Wayne C. Palmer’s “Research Paper No. 45: Meteorological Drought,” was there even a complex mathematical definition of drought. …


An Assessment Of The Filling Process Of The Grand Ethiopian Renaissance Dam And Its Impact On The Downstream Countries, Prakrut Kansara, Wenzhao Li, Hesham El-Askary, Venkat Lakshmi, Thomas Piechota, Daniele Struppa, Mohamed Abdelaty Sayed Feb 2021

An Assessment Of The Filling Process Of The Grand Ethiopian Renaissance Dam And Its Impact On The Downstream Countries, Prakrut Kansara, Wenzhao Li, Hesham El-Askary, Venkat Lakshmi, Thomas Piechota, Daniele Struppa, Mohamed Abdelaty Sayed

Mathematics, Physics, and Computer Science Faculty Articles and Research

The Grand Ethiopian Renaissance Dam (GERD), formerly known as the Millennium Dam, has been filling at a fast rate. This project has created issues for the Nile Basin countries of Egypt, Sudan, and Ethiopia. The filling of GERD has an impact on the Nile Basin hydrology and specifically the water storages (lakes/reservoirs) and flow downstream. In this study, through the analysis of multi-source satellite imagery, we study the filling of the GERD reservoir. The time-series generated using Sentinel-1 SAR imagery displays the number of classified water pixels in the dam from early June 2017 to September 2020, indicating a contrasting …


Flash Drought Onset Over The Contiguous United States: Sensitivity Of Inventories And Trends To Quantitative Definitions, Mahmoud Osman, Bejamin F. Zaitchik, Hamada S. Badr, Jordan I. Christian, Tsegaye Tadesse, Jason A. Otkin, Martha C. Anderson Feb 2021

Flash Drought Onset Over The Contiguous United States: Sensitivity Of Inventories And Trends To Quantitative Definitions, Mahmoud Osman, Bejamin F. Zaitchik, Hamada S. Badr, Jordan I. Christian, Tsegaye Tadesse, Jason A. Otkin, Martha C. Anderson

National Drought Mitigation Center: Faculty Publications

The term “flash drought” is frequently invoked to describe droughts that develop rapidly over a relatively short timescale. Despite extensive and growing research on flash drought processes, predictability, and trends, there is still no standard quantitative definition that encompasses all flash drought characteristics and pathways. Instead, diverse definitions have been proposed, supporting wide-ranging studies of flash drought but creating the potential for confusion as to what the term means and how to characterize it. Use of different definitions might also lead to different conclusions regarding flash drought frequency, predictability, and trends under climate change. In this study, we compared five …


Valuation Of Drought Information: Understanding The Value Of The Us Drought Monitor In Land Management, Tingting Liu, Richard Krop, Tonya Haigh, Kelly Helm Smith, Mark D. Svoboda Jan 2021

Valuation Of Drought Information: Understanding The Value Of The Us Drought Monitor In Land Management, Tingting Liu, Richard Krop, Tonya Haigh, Kelly Helm Smith, Mark D. Svoboda

National Drought Mitigation Center: Faculty Publications

Droughts affect recreation and tourism, grazing, forests, and timber, and can have important indirect effects for the ecosystems and species that rely on water. Despite its importance, the effect of drought in the land management sector is less understood than in other water-intensive sectors, such as agriculture and public water supplies. This study presents the first-ever estimates of the economic valuation of the information provided by the U.S. Drought Monitor using the avoided cost method. These estimates are based on the time and labor saved by using the U.S. Drought Monitor rather than compiling drought-related information from other sources, or …


Ranchers’ Use Of Drought Contingency Plans In Protective Action Decision Making, Tonya Haigh, Michael Hayes, Jolene Smyth, Linda Stalker Prokopy, Charles A. Francis, Mark Burbach Jan 2021

Ranchers’ Use Of Drought Contingency Plans In Protective Action Decision Making, Tonya Haigh, Michael Hayes, Jolene Smyth, Linda Stalker Prokopy, Charles A. Francis, Mark Burbach

National Drought Mitigation Center: Faculty Publications

Drought contingency planning is an increasingly common tool in the ranchers’ climate adaptation toolboxes, but its effect on drought response has not yet been evaluated. We use cognitive models of protective action decision making and planning to explore the effects of having a drought plan on the use of drought early warning information and drought response (and timing). Results of a cross-sectional, probability-based survey of livestock producers affected by a 2016 flash-drought are used to describe the characteristics of operations with drought plans and provide evidence of whether having a plan predicts drought information use and response. While larger operations …


Whose Ground Truth Is It? Harvesting Lessons From Missouri’S 2018 Bumper Crop Of Drought Observations, Kelly Helm Smith, Mark E. Burbach, Michael Hayes, Patrick Guinan, Andrew Tyre, Brian Fuchs, Tonya Haigh, Mark Svoboda Jan 2021

Whose Ground Truth Is It? Harvesting Lessons From Missouri’S 2018 Bumper Crop Of Drought Observations, Kelly Helm Smith, Mark E. Burbach, Michael Hayes, Patrick Guinan, Andrew Tyre, Brian Fuchs, Tonya Haigh, Mark Svoboda

National Drought Mitigation Center: Faculty Publications

Drought-related decision-making and policy should go beyond numeric hydrometeorological data to incorporate information on how drought affects people, livelihoods, and ecosystems. The effects of drought are nested within environmental and human systems, and relevant data may not exist in readily accessible form. For example, drought may reduce forage growth, compounded by both late-season freezes and management decisions. An effort to gather crowdsourced drought observations in Missouri in 2018 yielded a much higher number of observations than did previous related efforts. Here we examine 1) the interests, circumstances, history, and recruitment messaging that coincided to produce a high number of reports …


Tweetdrought: A Deep-Learning Drought Impacts Recognizer Based On Twitter Data, Beichen Zhang, Frank Schilder, Kelly Helm Smith, Michael Hayes, Sherri Harms, Tsegaye Tadesse Jan 2021

Tweetdrought: A Deep-Learning Drought Impacts Recognizer Based On Twitter Data, Beichen Zhang, Frank Schilder, Kelly Helm Smith, Michael Hayes, Sherri Harms, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

Acquiring a better understanding of drought impacts becomes increasingly vital under a warming climate. Traditional drought indices describe mainly biophysical variables and not impacts on social, economic, and environmental systems. We utilized natural language processing and bidirectional encoder representation from Transformers (BERT) based transfer learning to fine-tune the model on the data from the news-based Drought Impact Report (DIR) and then apply it to recognize seven types of drought impacts based on the filtered Twitter data from the United States. Our model achieved a satisfying macro-F1 score of 0.89 on the DIR test set. The model was then applied to …


Developing A Strategy For The National Coordinated Soil Moisture Monitoring Network, Michael H. Cosh, Todd G. Caldwell, C. Bruce Baker, John D. Bolten, Nathan Edwards, Peter Goble, Heather Hofman, Tyson E. Ochsner, Steven Quiring, Charles Schalk, Marina Skumanich, Mark D. Svoboda, Mary E. Woloszyn Jan 2021

Developing A Strategy For The National Coordinated Soil Moisture Monitoring Network, Michael H. Cosh, Todd G. Caldwell, C. Bruce Baker, John D. Bolten, Nathan Edwards, Peter Goble, Heather Hofman, Tyson E. Ochsner, Steven Quiring, Charles Schalk, Marina Skumanich, Mark D. Svoboda, Mary E. Woloszyn

National Drought Mitigation Center: Faculty Publications

Soil moisture is a critical land surface variable, affecting a wide variety of climatological, agricultural, and hydrological processes. Determining the current soil moisture status is possible via a variety of methods, including in situ monitoring, remote sensing, and numerical modeling. Although all of these approaches are rapidly evolving, there is no cohesive strategy or framework to integrate these diverse information sources to develop and disseminate coordinated national soil moisture products that will improve our ability to understand climate variability. The National Coordinated Soil Moisture Monitoring Network initiative has developed a national strategy for network coordination with NOAA’s National Integrated Drought …


Evaluation Of Remotely Sensed Precipitation Estimates From The Nasa Power Project For Drought Detection Over Jordan, Muhammad Rasool Al‑Kilani, Michel Rahbeh, Jawad Al‑Bakri, Tsegaye Tadesse, Cody Knutson Jan 2021

Evaluation Of Remotely Sensed Precipitation Estimates From The Nasa Power Project For Drought Detection Over Jordan, Muhammad Rasool Al‑Kilani, Michel Rahbeh, Jawad Al‑Bakri, Tsegaye Tadesse, Cody Knutson

National Drought Mitigation Center: Faculty Publications

Droughts can cause devastating impacts on water and land resources and therefore monitoring these events forms an integral part of planning. The most common approach for detecting drought events and assessing their intensity is use of the Standardized Precipitation Index (SPI), which requires abundant precipitation records at good spatial distribution. This may restrict SPI usage in many regions around the world, particularly in areas with limited numbers of ground meteorological stations. Therefore, the use of remotely sensed derived data of precipitation can contribute to drought monitoring. In this study, remotely sensed precipitation estimates from the POWER/Agroclimatology archive of NASA and …


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 …


Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow Jan 2021

Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Currently little is known of newer pesticide classes and their occurrence and persistence in recreational lakes. Therefore, the objectives of this study were to (1) assess average pesticide concentrations and loadings entering recreational lakes in three mixed land use watersheds throughout the growing season, (2) evaluate pesticide persistence longitudinally within the lakes, and (3) perform an ecotoxicity assessment. Six sampling campaigns were conducted at three lakes from April through October 2018 to measure the occurrence and persistence during pre, middle, and post growing season. Polar organic chemical integrative samplers (POCIS) were placed in streams near lake inlets and monthly samples …


Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow Jan 2021

Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Dissolved arsenic typically results from chemical weathering of arsenic rich sediments and is most often found in oxidized forms in surface water. The mobility of arsenic is controlled by its valence state and also by its association with iron oxides minerals, the forms of which are both influenced by abiotic and biotic processes in aqueous environment. In this study, speciation methods were used to measure and confirm the presence of reduced arsenic species in the surface water of Frenchman creek, a gaining stream that crosses the Colorado- Nebraska border. Selective extraction analysis of aquifer and stream bed sediments shows that …


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


A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles Jan 2021

A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles

Master's Theses or Doctor of Nursing Practice

Investigation into surface karst formation is significant to hazard prediction, hydrogeologic drainage, and land management. Southeast Alaska contains over 600,000 acres of mapped carbonate bedrock, and some of the fastest recorded karst dissolution in the world. The objectives of this study are to develop and compare multiple semi-automated models to map and delineate karst features from bare-earth LiDAR imagery using ArcGIS Desktop 10.7, and to apply a preliminary geostatistical analysis of sinkhole morphometric parameters to highlight potential spatial patterns of karst evolution on Prince of Wales Island, Alaska. A semi-automated approach of mapping karst features provides a dataset that minimizes …


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 Jan 2021

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 …


Building An Improved Drought Climatology Using Updated Drought Tools: A New Mexico Food-Energy-Water (Few) Systems Focus, Lindsay E. Johnson, Hatim M.E. Geli, Michael J. Hayes, Kelly Helm Smith Dec 2020

Building An Improved Drought Climatology Using Updated Drought Tools: A New Mexico Food-Energy-Water (Few) Systems Focus, Lindsay E. Johnson, Hatim M.E. Geli, Michael J. Hayes, Kelly Helm Smith

National Drought Mitigation Center: Faculty Publications

Drought is a familiar climatic phenomenon in the United States Southwest, with complex human-environment interactions that extend beyond just the physical drought events. Due to continued climate variability and change, droughts are expected to become more frequent and/or severe in the future. Decision-makers are charged with mitigating and adapting to these more extreme conditions and to do that they need to understand the specific impacts drought has on regional and local scales, and how these impacts compare to historical conditions. Tremendous progress in drought monitoring strategies has occurred over the past several decades, with more tools providing greater spatial and …


An Assessment Of The Hydrological Trends Using Synergistic Approaches Of Remote Sensing And Model Evaluations Over Global Arid And Semi-Arid Regions, Wenzhao Li, Hesham El-Askary, Rejoice Thomas, Surya Prakash Tiwari, Karuppasamy Manikandan, Thomas Piechota, Daniele Struppa Dec 2020

An Assessment Of The Hydrological Trends Using Synergistic Approaches Of Remote Sensing And Model Evaluations Over Global Arid And Semi-Arid Regions, Wenzhao Li, Hesham El-Askary, Rejoice Thomas, Surya Prakash Tiwari, Karuppasamy Manikandan, Thomas Piechota, Daniele Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Drylands cover about 40% of the world’s land area and support two billion people, most of them living in developing countries that are at risk due to land degradation. Over the last few decades, there has been warming, with an escalation of drought and rapid population growth. This will further intensify the risk of desertification, which will seriously affect the local ecological environment, food security and people’s lives. The goal of this research is to analyze the hydrological and land cover characteristics and variability over global arid and semi-arid regions over the last decade (2010–2019) using an integrative approach of …


Characterizing El Niño-Southern Oscillation Effects On The Blue Nile Yield And The Nile River Basin Precipitation Using Empirical Mode Decomposition, Justin A. Le, Hesham El-Askary, Mohamed Allali, Eman Sayed, Hani Sweliem, Thomas C. Piechota, Daniele C. Struppa Nov 2020

Characterizing El Niño-Southern Oscillation Effects On The Blue Nile Yield And The Nile River Basin Precipitation Using Empirical Mode Decomposition, Justin A. Le, Hesham El-Askary, Mohamed Allali, Eman Sayed, Hani Sweliem, Thomas C. Piechota, Daniele C. Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Using new mathematical and data-driven techniques, we propose new indices to measure and predict the strength of different El Niño events and how they affect regions like the Nile River Basin (NRB). Empirical Mode Decomposition (EMD), when applied to Southern Oscillation Index (SOI), yields three Intrinsic Mode Functions (IMF) tracking recognizable and physically significant non-stationary processes. The aim is to characterize underlying signals driving ENSO as reflected in SOI, and show that those signals also meaningfully affect other physical processes with scientific and predictive utility. In the end, signals are identified which have a strong statistical relationship with various physical …


Forest Drought Response Index (Fordri): A New Combined Model To Monitor Forest Drought In The Eastern United States, Tsegaye Tadesse, David Y. Hollinger, Yared A. Bayissa, Mark Svoboda, Brian Fuchs, Beichen Zhang, Getachew Demissie, Brian D. Wardlow, Gil Bohrer, Kenneth L. Clark, Ankur R. Desai, Lianhong Gu, Asko Noormets, Kimberly A. Novick, Andrew D. Richardson Nov 2020

Forest Drought Response Index (Fordri): A New Combined Model To Monitor Forest Drought In The Eastern United States, Tsegaye Tadesse, David Y. Hollinger, Yared A. Bayissa, Mark Svoboda, Brian Fuchs, Beichen Zhang, Getachew Demissie, Brian D. Wardlow, Gil Bohrer, Kenneth L. Clark, Ankur R. Desai, Lianhong Gu, Asko Noormets, Kimberly A. Novick, Andrew D. Richardson

National Drought Mitigation Center: Faculty Publications

Monitoring drought impacts in forest ecosystems is a complex process because forest ecosystems are composed of different species with heterogeneous structural compositions. Even though forest drought status is a key control on the carbon cycle, very few indices exist to monitor and predict forest drought stress. The Forest Drought Indicator (ForDRI) is a new monitoring tool developed by the National Drought Mitigation Center (NDMC) to identify forest drought stress. ForDRI integrates 12 types of data, including satellite, climate, evaporative demand, ground water, and soil moisture, into a single hybrid index to estimate tree stress. The model uses Principal Component Analysis …


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 …


Seasonal Grassland Productivity Forecast For The U.S. Great Plains Using Grass-Cast, Melannie D. Hartman, William J. Parton, Justin D. Derner, Darin K. Schulte, William K. Smith, Dannele E. Peck, Ken A. Day, Stephen J. Del Grosso, Susan Lutz, Brian Fuchs, Maosi Chen, Wei Gao Nov 2020

Seasonal Grassland Productivity Forecast For The U.S. Great Plains Using Grass-Cast, Melannie D. Hartman, William J. Parton, Justin D. Derner, Darin K. Schulte, William K. Smith, Dannele E. Peck, Ken A. Day, Stephen J. Del Grosso, Susan Lutz, Brian Fuchs, Maosi Chen, Wei Gao

National Drought Mitigation Center: Faculty Publications

Every spring, ranchers in the drought-prone U.S. Great Plains face the same difficult challenge —trying to estimate how much forage will be available for livestock to graze during the upcoming summer grazing season. To reduce this uncertainty in predicting forage availability, we developed an innovative new grassland productivity forecast system, named Grass-Cast, to provide science-informed estimates of growing season aboveground net primary production (ANPP). Grass-Cast uses over 30 yr of historical data including weather and the satellite-derived normalized vegetation difference index (NDVI)—combined with ecosystem modeling and seasonal precipitation forecasts—to predict if rangelands in individual counties are likely to produce below-normal, …


A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow Oct 2020

A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Kabul is one of the most populated cities in Afghanistan and providing resources to support this population in an arid climate presents a serious environmental challenge. The current study evaluated the quality of local Kabul Basin groundwater to determine its suitability water for drinking and irrigation purposes now and into the future. This aim was aided through groundwater parameter assessment as well as determination ofWater Quality Index (WQI) developed from 15 observation points near the city. The results of our physicochemical analysis illustrate that groundwater in the majority of areas of the Kabul Basin is not generally suitable for human …


A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow Oct 2020

A Detailed Assessment Of Groundwater Quality In The Kabul Basin, Afghanistan, And Suitability For Future Development, Hussain Ali Jawadi, Jay Sagin, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Abstract: Kabul is one of the most populated cities in Afghanistan and providing resources to support this population in an arid climate presents a serious environmental challenge. The current study evaluated the quality of local Kabul Basin groundwater to determine its suitability water for drinking and irrigation purposes now and into the future. This aim was aided through groundwater parameter assessment as well as determination ofWater Quality Index (WQI) developed from 15 observation points near the city. The results of our physicochemical analysis illustrate that groundwater in the majority of areas of the Kabul Basin is not generally suitable for …