Engineering Commons^™

A Greenhouse Gas Emissions Inventory For Nebraska: Livestock And Coal Loom Large, Eric R. Holley, Adam Liska

Adam Liska Papers

Mitigation of climate change requires the systematic identification and cataloging of emissions sources at city, state, and national levels. In this study, an inventory of annual greenhouse gas emissions from the state of Nebraska was created based on industry data, and emissions inventories were completed each year from 1990 to 2016. Nebraska’s net emissions were found to increase from 56.2 million metric tons of carbon dioxide equivalents (MMtCO₂e) in 1990 to 87.4 MMtCO₂e in 2016. Agriculture was found to be the sector with the most emissions (36 MMtCO₂e) followed by electricity generation (21 MMtCO …

Greenhouse Gas Emissions And Drought Projections For Nebraska, Adam Liska

Adam Liska Papers

This lecture will focus on three issues. The first is a presentation of data from the first greenhouse gas emissions inventory for the State of Nebraska, which will be published in the coming weeks. In 2016, emissions from beef cattle made up 23% of net state emissions, and coal for electricity made up 23.7% of net state emissions. The second issue to be addressed are the impacts of the 2012 drought on agriculture in Nebraska and the region. The drought of 2012 indicates that future droughts in the 21^st century in the region can be a dominant influence on …

Climate Change And Market-Based Insurance Feedbacks, Eric R. Holley, Adam Liska, Cory Walters, Geoffrey C. Friesen, Michael Hayes, Max J. Rudolph, Donald A. Wilhite

Adam Liska Papers

Climatic events have accounted for 91% of $1.05 trillion in insured costs for global catastrophic events from 1980 to 2016. Costs are driven by socio-economic development and increased frequency and severity of climatic disasters driven by climate change. Government policies to reduce systemic risk (e.g., cap-and-trade, carbon tax) have been a predominant approach for mitigation and adaptation. Alternatively, market-based incentives for climate change adaptation and mitigation already operate via the insurance industry to lessen impacts on society. Insurance feedbacks include changes in 1) premiums and insurance policies, 2) non-coverage, and 3) policy making and litigation. Alongside government policies, insurance feedbacks …

The Fluxnet2015 Dataset And The Oneflux Processing Pipeline For Eddy Covariance Data, Gilberto Pastorello, Timothy Arkebauer, Dave P. Billesbach, Anatoly Gitelson, Adam Liska, Andrew Suyker, Elizabeth Walter-Shea, More Than 200 Other

Adam Liska Papers

The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as …

Modeled And Measured Ecosystem Respiration In Maize–Soybean Systems Over 10 Years, Ming Zhan, Adam Liska, Anthony Nguy-Robertson, Andrew E. Suyker, Matthew P. Pelton, Haishun Yang

Adam Liska Papers

Crop residue is an abundant resource for the potential production of biofuels, but a better understanding of its use on net carbon emissions must be developed to mitigate climate change. This analysis combines two established crop growth models (Hybrid-Maize and SoySim) with a simple soil and crop residue respiration model to estimate daily ecosystem respiration (ERe) from maize and soybean; ERe was estimated to be the sum of CO₂ emissions from the oxidation of the growing crop, crop residue, and soil organic carbon (SOC). Model-estimated CO₂ fluxes from irrigated continuous maize and irrigated maize–soybean cropping systems in eastern …

Water, Energy, And Carbon Footprints Of Bioethanol From The U.S. And Brazil, Mesfin Mekonnen, Thiago L. Romanelli, Chittaranjan Ray, Arjen Y. Hoekstra, Adam Liska, Christopher M. U. Neale

Adam Liska Papers

Driven by biofuel policies, which aim to reduce greenhouse gas (GHG) emissions and increase domestic energy supply, global production and consumption of bioethanol have doubled between 2007 and 2016, with rapid growth in corn-based bioethanol in the U.S. and sugar cane-based bioethanol in Brazil. Advances in crop yields, energy use efficiency in fertilizer production, biomass-to-ethanol conversion rates, and energy efficiency in ethanol production have improved the energy balance and GHG emission reduction potential of bioethanol. In the current study, the water, energy, and carbon footprints of bioethanol from corn in the U.S. and sugar cane in Brazil were assessed. The …

Adam J. Liska: Curriculum Vitae, Adam Liska

Adam Liska Papers

Associate Professor, George Dempster Smith Chair of Industrial Ecology, Departments of Biological Systems Engineering and Agronomy & Horticulture, University of Nebraska-Lincoln 236 L.W. Chase Hall, Lincoln, NE 68583-0726, Ph: (402) 472-8744, e-mail: aliska2@unl.edu

Ph.D. 2003 Biology (magna cum laude), Max Planck Institute of Molecular Cell Biology & Genetics, Technische Universität Dresden, Dresden, Germany

Biofuels From Crop Residue: Soil Organic Carbon And Climate Impacts In The Us And India, Adam Liska

Adam Liska Papers

The transformation of crop residue to soil organic carbon and CO₂ is a conserved process that occurs globally. Due to the mathematics of carbon intensity calculations found in government regulations, the amount of CO₂ emitted from crop residue per unit of energy in biofuel is largely independent of the amount of residue removed and the location of its removal, as shown by results from the US and India.

Soil organic carbon (SOC) levels are at equilibria determined by carbon inputs from plant material (+I_c) and loss from oxidation to CO₂

Are the US results relevant …

Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby

Adam Liska Papers

Many people tend to think that the outcome of any nuclear weapons use today will result in an escalatory situation with apocalyptic outcomes for the countries involved. Yet many factors are increasing the probability of the limited use of nuclear weapons (e.g., 1 to 20 warheads) in a range of conflict scenarios. Previous atmospheric model simulations of regional nuclear conflicts employing many relatively small bombs have been estimated to cause a global “nuclear autumn,” with great reductions in agricultural productivity, stratospheric ozone loss, and spread of hazardous radioactive fallout. The totality of these effects would result in widespread damage …

Biofuels From Crop Residue: Soil Organic Carbon And Climate Impacts In The Us And India, Adam J. Liska

Adam Liska Papers

Soil organic carbon (SOC) levels are the balance of carbon inputs from plant material and loss from oxidation to CO₂ (SOC = I_C - kC_oc) SOC tends to decrease as atmospheric temperature increases.

In the US, SOC levels are highest in the north central region (Iowa) where maize & soybean are grown at high yields.

In the US, gross energy yield of biofuel production can be increased by using both maize grain & maize residue.

Are the US results relevant for India if crop residues are used for biofuels?

India’s estimated biomass production & potential in …

Ensc 110 (Energy In Perspective) Bibliography, Supplementary Reading, Adam Liska

Adam Liska Papers

Energy, Thermodynamics, Complexity, Evolution, & Astronomy
Energy & Technology
Energy: Petroleum & Coal
Bioenergy, Animals, & Food
Energy & Environment
Energy & Climate Change
Energy, Oil Security, & War
Energy & Societal Collapse

Bibliography of 47 monographs

Ensc 300 (Energy Seminar) Annotated Bibliography, Supplementary Reading, Adam Liska

Adam Liska Papers

Innovation
Sociology of Innovation, Business, & Work
Sustainable Business Strategy
Leadership
Science, Engineering, & Business History
Economics
Energy, Business, & Environmental Policy
Climate Change & Insurance
Education
Ethics

62 monographic resources

Greenhouse Gas Emissions Inventory Of The Centalized Renewable Energy System (Cres) At Nebraska Innovation Campus, Matan Gill, Adam Liska

Adam Liska Papers

The Centralized Renewable Energy System (CRES) at Nebraska Innovation Campus (NIC) is a heat-exchanger system that utilizes reclaimed, non-drinkable water from the nearby water treatment plant to heat and cool a projected 1.675 million square feet of office and lab space. A greenhouse gas emissions inventory was estimated for the CRES operating at full build-out of the campus in 2035, compared to conventional office space, being a control system with standard chiller and boiler configuration. The control system is estimated to emit 30,787 metric tons of carbon dioxide-equivalent per year (Mg CO₂e yr-1), whereas heating and cooling Nebraska …

Eight Principles Of Uncertainty For Life Cycle Assessment Of Biofuel Systems, Adam J. Liska

Adam Liska Papers

New environmental regulations in the USA and Europe require a reduction of greenhouse gas (GHG) emissions from transportation fuels as a component of climate change mitigation policy. The US Energy Independence and Security Act of 2007 (EISA) requires GHG emission reductions from the life cycles of biofuels compared to gasoline, by 20% for ethanol from maize grain (maize-ethanol), 60% for cellulosic ethanol, and 50% for other advanced biofuels. To determine these reductions, the US Environmental Protection Agency (EPA) employs life cycle assessment (LCA) methods which were not used previously in national environmental regulations. These regulations, entitled the “Renewable Fuel Standard …

The Myth And The Meaning Of Science As A Vocation, Adam Liska

Adam Liska Papers

Many natural scientists of the past and the present have imagined that they pursued their activity according to its own inherent rules in a realm distinctly separate from the business world, or at least in a realm where business tended to interfere with science from time to time, but was not ultimately an essential component, ‘because one thought that in science one possessed and loved something unselfish, harmless, self-sufficient, and truly innocent, in which man’s evil impulses had no part whatever’, as Nietzsche once commented (Nietzsche 1974, p.106). With the extreme technological changes that have occurred in the last fifty …

Reply To ‘Co2 Emissions From Crop Residue-Derived Biofuels’, Adam Liska, Haishun Yang, Matthew P. Pelton, Andrew E. Suyker

Adam Liska Papers

The soil organic carbon (SOC) model that we used was parameterized with data from arable land under normal farming conditions in North America, Europe, Africa and Asia, but the equation is insensitive to changes in tillage, soil texture and moisture. The model has reasonable accuracy, however, in predicting changes in SOC, residue remaining and CO₂ emissions from initial SOC, carbon inputs from residue, and daily temperature; the shoot-to-root ratio used in the geospatial simulation was 0.29 (that is, root carbon is 29% of total aboveground carbon), which did not underestimate carbon input to soil (Supplementary Figure 2 in Ref. …

Agricultural Industry Advanced Vehicle Technology: Benchmark Study For Reduction In Petroleum Use, Roger M. Hoy, Rodney Rohrer, Adam Liska, Joe D. Luck, Loren Isom, Deepak R. Keshwani

Adam Liska Papers

Diesel use on farms in the United States has remained relatively constant since 1985, decreasing slightly in 2009, which may be attributed to price increases and the economic recession (Figure 1). During this time, the United States’ harvested area also has remained relatively constant at roughly 300 million acres. In 2010, farm diesel use was 5.4% of the total United States diesel use. Crops accounting for an estimated 65% of United States farm diesel use include corn, soybean, wheat, hay, and alfalfa, respectively, based on harvested crop area and a recent analysis of estimated fuel use by crop (Figure 2).1 …

Uncertainties In Life Cycle Greenhouse Gas Emissions From U.S. Beef Cattle, Quentin M. Dudley, Adam Liska, Andrea K. Watson, Galen E. Erickson

Adam Liska Papers

Beef cattle feedlots are estimated to contribute 26% of U.S. agricultural greenhouse gas (GHG) emissions, and future climate change policy could target reducing these emissions. Life cycle assessment (LCA) of GHG emissions from U.S. grain-fed beef cattle was conducted based on industry statistics and previous studies to identify the main sources of uncertainty in these estimations. Uncertainty associated with GHG emissions from indirect land use change, pasture soil emissions (e.g. soil carbon sequestration), enteric fermentation from cattle on pasture, and methane emissions from feedlot manure, respectively, contributed the most variability to life cycle GHG emissions from beef production. Feeding of …

Biofuels From Crop Residue Can Reduce Soil Carbon And Increase Co2 Emissions, Adam J. Liska, Haishun Yang, Maribeth Milner, Steve Goddard, Humberto Blanco-Canqui, Matthew P. Pelton, Xiao X. Fang, Haitao Zhu, Andrew E. Suyker

Adam Liska Papers

Removal of corn residue for biofuels can decrease soil organic carbon(SOC) and increase CO₂ emissions because residue C in biofuels is oxidized to CO₂ at a faster rate than when added to soil. Net CO2 emissions from residue removal are not adequately characterized in biofuel life cycle assessment (LCA). Here we used a model to estimate CO₂ emissions from corn residue removal across the US Corn Belt at 580 million geospatial cells. To test the SOC model, we compared estimated daily CO₂ emissions from corn residue and soil with CO₂ emissions measured using eddy covariance, …

Accounting For Indirect Land-Use Change In The Life Cycle Assessment Of Biofuel Supply Chains, Susan Tarka Sanchez, Jeremy Woods, Mark Akhurst, Matthew Brander, Michael O'Hare, Terence P. Dawson, Robert Edwards, Adam J. Liska, Rick Malpas

Adam Liska Papers

The expansion of land used for crop production causes variable direct and indirect greenhouse gas emissions; and other economic, social and environmental effects. We analyze the use of life cycle analysis (LCA) for estimating the carbon intensity of biofuel production from indirect land-use change (ILUC). Two approaches are critiqued; direct, attributional life cycle analysis (ALCA) and consequential life cycle analysis (CLCA). A proposed hybrid “combined model” of the two approaches for ILUC analysis relies on first defining the system boundary of the resulting full LCA. Choices are then made as to the modeling methodology (economic equilibrium or cause-effect), data inputs, …

Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer

Adam Liska Papers

Quantifying energy issues associated with agricultural systems, even for a two-crop corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) rotation, is not a simple task. It becomes even more complicated if the goal is to include all aspects of sustainability (i.e., economic, environmental, and social). This Issue Paper examines energy issues associated with and affecting corn/soybean rotations by first defining the size of the system from both a U.S. and global perspective and then establishing boundaries based on the Farm Bill definition of sustainability. This structured approach is essential to help quantify energy issues within corn/soybean …

Climate Change Policy Could Make Keystone Xl Obsolete, Adam Liska

Adam Liska Papers

Clearly the Keystone XL pipeline threatens both surface and ground water that sustains the agricultural economy of Nebraska, but the projected profitability of tar sands oil and the pipeline operation are dependent on the future economics of climate change. Three recent scientific studies estimate the total carbon intensity of tar sands-based gasoline from Alberta (from both production and burning of the fuel) at an average of roughly 22 percent higher than U.S. gasoline in 2005, with the range of average carbon intensities for tar sands-gasoline at 16 to 27 percent higher than most other sources.

Life Cycle Assessment Of Greenhouse Gas Emissions From Ethanol And Biopolymers, Adam J. Liska, Xiao Xue Fang

Adam Liska Papers

Conclusions

• Regulatory LCA is not likely to be used for non‐fuel chemicals alone in the near future

• Significant GHG emission credits for corn‐ethanol can be obtained by using only roughly 6‐9% of initial starch for production of biopolymers based on previous LCA theory

• Pay close attention to values in calculating credits per kg—these have to stand up in litigation to ensure the credit

• Credits are proportional to the mass of polymer produced

• Many theoretical issues are uncertain and credits will only be determined in conjunction with EPA

• Indirect emissions are uncertain and are a …

Effect Of Distillers Grains Moisture And Inclusion Level In Livestock Diets On Greenhouse Gas Emissions In The Corn-Ethanol-Livestock Life Cycle, Virgil R. Bremer, Andrea K. Watson, Adam J. Liska, Galen Erickson, Kenneth Cassman, Kathryn J. Hanford, Terry Klopfenstein

Adam Liska Papers

A model was previously developed (Biofuel Energy Systems Simulator; www. bess.unl.edu) to predict greenhouse gas (GHG) emissions and net energy yield when ethanol is produced from corn. The model also predicts feedlot cattle, dairy cattle, and swine performance and feed replacement value of ethanol coproducts. Updated equations that predict performance of feedlot cattle fed 0 to 40% of dietary DM as corn wet (WDGS), modified (MDGS), or dry (DDGS) distillers grains plus solubles replacing dry-rolled and high-moisture corn were developed and incorporated into the model. Equations were derived from pen-level performance for 20 finishing studies evaluating WDGS, 4 evaluating MDGS, …

Energy And Climate Implications For Agricultural Nutrient Use Efficiency, Adam J. Liska, Richard K. Perrin

Adam Liska Papers

Energy and climate change are beginning to dominate the global political agenda and will drive policy formation that will shape the future of agriculture. Energy issues threaten national security and economic stability, as well as access to low-cost nutrient inputs for agriculture. Climate change has the potential to cause serious disruption to agricultural productivity. Paradoxically, nutrient use in agriculture to increase crop yields has the potential to negatively impact climate. This chapter will discuss recent and future energy and climate trends, the relationships between agricultural nutrient use efficiency and biofuels, and how global land limitations will shape agriculture in the …

Uncertainty In Indirect Land Use Change Emissions In The Life Cycle Of Biofuels: Implications For Legislation, Adam Liska

Adam Liska Papers

Current EPA life cycle analysis (LCA) of greenhouse gas (GHG) emissions from corn-ethanol will be the foundation for regulations for advanced biofuels. It appears regulatory policies that include emissions from indirect land use change (and other indirect emissions) in the biofuel life cycle are moving faster than the underlying science; there is no comparable scientific study that approaches the complexity in methods currently used by the EPA. There is substantial uncertainty in quantifying direct and indirect emissions from fuels, as evidenced by conflicting results from state and federal regulators and from within the scientific community. If indirect emissions from land …

Life Cycle Greenhouse Gas Emissions From Biofuels: Variability, Uncertainty, And Steps Toward Accurate Regulation, Adam J. Liska, Bruce E. Dale

Adam Liska Papers

a)Variability in life cycle greenhouse gas (GHG) emissions from corn-ethanol:
biorefineries
cropping systems
co-product feeding to livestock

b) EPA regulation of life cycle GHG emissions from biofuels & use of life cycle analysis (LCA):
uncertainties & inaccuracies
indirect effects

c) Building accurate knowledge infrastructure, theory, and research teams for accurate LCA methods for biofuels

Responses To “Comment On ‘Response To Plevin: Implications For Life Cycle Emissions Regulations’” And “Assessing Corn Ethanol: Relevance And Responsibility”, Adam Liska, Kenneth Cassman

Adam Liska Papers

This letter responds to two issues concerning the greenhouse gas (GHG) emissions intensity of corn-ethanol that were raised in discussions of our response (Liska and Cassman 2009) to Plevin’s article (2009), which critiques our original research (Liska et al. 2009) published in the Journal of Industrial Ecology. ... The suggestion by Anex and Lifset (2009) that corn-ethanol does not reduce GHG emissions by 47% compared to gasoline, but instead by “somewhere between” 35 to 40%, is unsubstantiated.

Bess: BIofuel ENergy SYstems SImulator: Life Cycle Energy & Emissions Analysis Model For Corn-Ethanol Biofuel Production Systems -- User’S Guide For The Bess Model, Adam Liska, Haishun Yang, Daniel T. Walters, Kenneth Cassman, Terry Klopfenstein, Galen Erickson, Virgil R. Bremer, Richard K. Koelsch, Dan Kenney, Patrick Tracy

Adam Liska Papers

The BESS model is a software tool to calculate the energy efficiency, greenhouse gas (GHG) emissions, and natural resource requirements of corn–to-ethanol biofuel production systems. The model provides a “cradle-to-grave” analysis of the production life cycle of biofuels from the creation of material inputs to finished products, producing an inventory of distributed GHG emissions from fossil fuels and a few key indirect emissions in the production life cycle. The model parameters can be set by the user to achieve the highest accuracy in evaluating a single corn-ethanol biorefinery and its surrounding feedstock crop production zone. The model equations and summary …

Magnitude And Variability In Emissions Savings In The Corn-Ethanol Life Cycle From Feeding Co-Products To Livestock, Virgil R. Bremer, Adam Liska, Terry J. Klopfenstein, Galen E. Erickson, Haishun Yang, Daniel T. Walters, Kenneth G. Cassman

Adam Liska Papers

Conclusions

• Co-product GHG emissions credit varied by >2-fold, from 11.5 to 28.3 gCO₂e per MJ of ethanol produced

• Co-product GHG emissions credit depend on
-types of co-products produced
-proportion fed to beef cattle vs. diary or swine
-location of corn production; the CP credit is highest in regions where GHG kg^-1grain are highest

• Depending on CP production types and feeding livestock classes, corn-ethanol net life cycle GHG intensity is 44-56 gCO₂e per MJ

• Midwest corn-ethanol reduces GHG emissions compared to gasoline by 47% on average, with co-products offsetting 23% of …