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Full-Text Articles in Physical Sciences and Mathematics

Effects Of Climate Variability On Wild Edible Plant Products: A Coping Strategy Applied By Pastoralists Of Northern Kenya, A. W. Kagunyu, J. W. Wanjohi Feb 2022

Effects Of Climate Variability On Wild Edible Plant Products: A Coping Strategy Applied By Pastoralists Of Northern Kenya, A. W. Kagunyu, J. W. Wanjohi

IGC Proceedings (1997-2023)

Drought which is a manifestation of climate variability has become a perennial problem in Kenya with chronic vulnerability being concentrated in Arid and Semi-Arid lands (ASALs). Traditionally, pastoralists have used wild edible plant products namely; fruits, vegetables and seeds as a coping strategy while faced by climate related calamities. However, recent studies have shown that pastoralists’ traditional coping strategies have become weak as a result of recurrent droughts. The overall objective of this study was to investigate the effects of climate variability on wild edible plant products. This study applied; household interviews (n=400), focus group discussions and key informant interviews …


Sources Of Variability And Uncertainty In Food-Energy-Water Nexus Systems, Heydi Calderon-Ambelis, Deepak R. Keshwani Jan 2022

Sources Of Variability And Uncertainty In Food-Energy-Water Nexus Systems, Heydi Calderon-Ambelis, Deepak R. Keshwani

Department of Biological Systems Engineering: Papers and Publications

A nexus approach contributes to the strategic allocation of resources to secure food, energy, and water for the world population. Integrated models considering the complex interactions across food, energy, and water (FEW) enhance decision-making and strategic planning towards resilience. However, a significant number of the existing integrated models leave unaddressed the inherent variability and uncertainty present in the FEW sectors. Here, we review the importance of characterizing variability over spatial and temporal scales and the importance of decreasing the uncertainty present within a FEW nexus systems. The review also discusses existing modeling tools that address variability and uncertainty on single …


Risk Of Climate-Related Impacts On Global Rangelands – A Review And Modelling Study, C. M. Godde, R. B. Boone, A. Ash, K. Waha, L. Sloat, P. Thornton, D. Mason-D’Croz, D. Mayberry, M. Herrero Oct 2021

Risk Of Climate-Related Impacts On Global Rangelands – A Review And Modelling Study, C. M. Godde, R. B. Boone, A. Ash, K. Waha, L. Sloat, P. Thornton, D. Mason-D’Croz, D. Mayberry, M. Herrero

IGC Proceedings (1997-2023)

Climate change threatens the ability of global rangelands to provide food, support livelihoods and deliver important ecosystems services. The extent and magnitude of potential impacts are however poorly understood. In this study, we review the risk of climate impacts along the rangeland systems food supply chain. We also present results from biophysical modelling simulations and spatial data analyses to identify where and to what extent rangelands may be at climatic risk. Although a quantification of the net impacts of climate change on rangeland production systems is beyond the reach of our current understanding, there is strong evidence that there will …


Collaborative Construction Of A Method That Contributes To Improve The Decision Making In Associative Ranches By Controlling The Grass Allowance In A Context Of Climate Variability, Emilio Duarte Esteves, Rómulo Cesar, Javier Fernández, Marcelo Ghelfi, Valentina Herrera, Virginia Caravia, Rodrigo Iribarne, Federico De Brum, Héctor Rodríguez, Marcelo Pereira Machín Oct 2021

Collaborative Construction Of A Method That Contributes To Improve The Decision Making In Associative Ranches By Controlling The Grass Allowance In A Context Of Climate Variability, Emilio Duarte Esteves, Rómulo Cesar, Javier Fernández, Marcelo Ghelfi, Valentina Herrera, Virginia Caravia, Rodrigo Iribarne, Federico De Brum, Héctor Rodríguez, Marcelo Pereira Machín

IGC Proceedings (1997-2023)

Pasture management and the particular conditions of each year are responsible for productive results, farm income, and condition of the pasture. A simple and robust method that relates the available grass and the required grass was built in a participatory manner, and contributes to a critical reflection process among the group of decision-making, adapting to their context. In 17 farms from the Basalt region in Uruguay, grass and animals were monitored seasonally. A simple method was developed with farmers, and from de offer needed to meet production targets (KgMS/KgPV) the amount of grass requires was calculated. The grass height was …


Response Of Coastal Ichthyoplankton Assemblages Off Northern California To Seasonal Oceanographic And Climate Variability, Blair M. Winnacott Jan 2021

Response Of Coastal Ichthyoplankton Assemblages Off Northern California To Seasonal Oceanographic And Climate Variability, Blair M. Winnacott

Cal Poly Humboldt theses and projects

This study analyzed samples collected along the Trinidad Head Line (41°N) to characterize variability in the ichthyoplankton assemblage in coastal waters off northern California from late 2007 through 2019, a period during which a major marine heatwave (MHW; late 2014-16) strongly perturbed the ecosystem. I augmented visual identification with genetic techniques to resolve the species composition of visually cryptic larval rockfishes (Sebastes spp.). While taxonomic composition off northern California was largely similar to studies off Oregon and Washington, and cross-shelf structure and seasonal patterns in species’ abundance were generally consistent with the distribution and phenology of parental stocks, interannual …


Productive And Sustainable Pasture Systems: Responding To Climate Variability In The South West Of Australia, Ned Crossley Dec 2020

Productive And Sustainable Pasture Systems: Responding To Climate Variability In The South West Of Australia, Ned Crossley

IGC Proceedings (1997-2023)

No abstract provided.


Socio‐Ecological Influences On Grazier Uptake Of Seasonal Climate Forecasts On The Rangelands In Australia, Nadine A. Marshall, A. J. Ash, I. J. Gordon, C. K. Mcdonald Nov 2020

Socio‐Ecological Influences On Grazier Uptake Of Seasonal Climate Forecasts On The Rangelands In Australia, Nadine A. Marshall, A. J. Ash, I. J. Gordon, C. K. Mcdonald

IGC Proceedings (1997-2023)

No abstract provided.


Inter-Annual Variability In Pasture Herbage Accumulation In Temperate Dairy Regions: Causes, Consequences, And Management Tools, David F. Chapman, Richard P. Rawnsley, Brendan R. Cullen, David A. Clark Jan 2020

Inter-Annual Variability In Pasture Herbage Accumulation In Temperate Dairy Regions: Causes, Consequences, And Management Tools, David F. Chapman, Richard P. Rawnsley, Brendan R. Cullen, David A. Clark

IGC Proceedings (1997-2023)

Inter-annual variation in pasture herbage accumulation rate (HAR) is common in temperate dairy regions, posing challenges for farmers in the management of dairy cow feeding and of pasture state. This paper reviews the biophysical factors that cause inter-annual variation, considers some of its consequences for the efficient harvest of pasture, and discusses the basis for decision rules and support tools that are available to assist New Zealand and Australian farmers to help manage the consequences of an imbalance between feed supply and demand. These tools are well-grounded in scientific research and farmer experience, but are not widely used in the …


Symmetry Of Energy Divergence Anomalies Associated With The El Niño-Southern Oscillation, Evan Kutta, Jason A. Hubbart, Timothy P. Eichler, Anthony R. Lupo Jan 2018

Symmetry Of Energy Divergence Anomalies Associated With The El Niño-Southern Oscillation, Evan Kutta, Jason A. Hubbart, Timothy P. Eichler, Anthony R. Lupo

Faculty & Staff Scholarship

The El Niño-Southern Oscillation (ENSO) is a dominant source of global climate variability. The effects of this phenomenon alter the flow of heat from tropical to polar latitudes, resulting in weather and climate anomalies that are difficult to forecast. The current work quantified two components of the vertically integrated equation for the total energy content of an atmospheric column, to show the anomalous horizontal redistribution of surface heat flux anomalies. Symmetric and asymmetric components of the vertically integrated latent and sensible heat flux divergence were quantified using ERA-Interim atmospheric reanalysis output on 30 model layers between 1979 and 2016. Results …


Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera Apr 2017

Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera

Geography and the Environment Faculty Publications

The Amazon basin has been subjected to unprecedented rates of land-use change over the past several decades, primarily as a result of the expansion of agriculture. Enhanced rain forest conservation efforts toward the end of the twentieth century slowed deforestation of the Amazon but, in turn, increased demand for land repurposing in the adjacent Cerrado (savanna) region, where conservation regulations are less strict. To maintain or increase yields while minimizing the need for additional land, agricultural producers adopted a form of intensification in which two rain-fed crops are planted within a single growing season (double cropping). Using 10 years (August …


Regional Variations Of Optimal Sowing Dates Of Maize For The Southwestern U.S., Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos Jan 2016

Regional Variations Of Optimal Sowing Dates Of Maize For The Southwestern U.S., Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Sowing date (SD) is sensitive to regional climate characteristics; thus, it is critical to systematically examine the effects of SD on crop yields for various temperature regimes. We performed a sensitivity study of SD for maize in the southwestern U.S. using the regionally extended version of the Agricultural Production Systems sIMulator (APSIM) model. The model was run utilizing North American Regional Reanalysis at a 32 km resolution from 1991 to 2011, with an irrigation threshold at 95% of the soil water-holding capacity. Two types of SD optimizations maximizing yield potential (Yp), varying spatially or interannually, revealed that the optimal SD …


Slides: Ag Water Sharing: Legal Challenges And Considerations, Peter D. Nichols Jun 2015

Slides: Ag Water Sharing: Legal Challenges And Considerations, Peter D. Nichols

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Peter D. Nichols, Esq., Partner, Berg, Hill, Greenleaf and Ruscitti, Boulder, CO

25 slides


Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group Jan 2015

Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group

Books, Reports, and Studies

40 pages (includes color illustrations).


Slides: Climate Comments, Bob Gough Jun 2008

Slides: Climate Comments, Bob Gough

Shifting Baselines and New Meridians: Water, Resources, Landscapes, and the Transformation of the American West (Summer Conference, June 4-6)

Presenter: Bob Gough, NativeEnergy, Inc.

11 slides


Crop Updates 2007 - Farming Systems, David Jeffries, A. Loi, B. J. Nutt, C. K. Revell, Yvette Oliver, Michael Robertson, Bill Bowden, Kit Leake, Ashley Bonser, Ian Maling, Bindi Isbister, Garren Knell, Alison Slade, David Stephens, Michael Meuleners, David Beard, Nicolyn Short, Rob Grima, Ingrid Richardson, Ruhi Ferdowsian, Geoff Bee, David Evans, Bob Gilkes, Senthold Asseng, Jim Dixon, Felicity Byrne, Mike Ewing, Dennis Van Gool, Louise Barton, Ralf Kiese, David Gatter, Klaus Butterbach-Bahl, Renee Buck, Christoph Hinz, Daniel Murphy, Cameron Weeks, Meredith Fairbanks, John Peirce, Brad Rayner, Sandy White, Paul Damon, Qifa Ma, Zed Rengel, Ed Barrett-Lennard, Meir Altman, Tracey M. Gianatti, Lindsay Bell, Ben Webb, Caroline Peek, Paul Sanford, Paul Blackwell, Glen Riethmuller, Darshan Sharma, Mike Collins, Frank D'Emden, David Hall, G. P. Manango, D. L. Steverson, Vanessa Stewart, Julie Roche, Peter Rutherford, Imma Farré, Ian Foster, Stephen Charles, Frances Hoyle, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Rob Sands, David Mccarthy, Paul Carmody, J. Russell, J. Eyres, G. Fosbery, A. Roe, Phil Nichols, Andrew Bathgate, Anne Wilkins Feb 2007

Crop Updates 2007 - Farming Systems, David Jeffries, A. Loi, B. J. Nutt, C. K. Revell, Yvette Oliver, Michael Robertson, Bill Bowden, Kit Leake, Ashley Bonser, Ian Maling, Bindi Isbister, Garren Knell, Alison Slade, David Stephens, Michael Meuleners, David Beard, Nicolyn Short, Rob Grima, Ingrid Richardson, Ruhi Ferdowsian, Geoff Bee, David Evans, Bob Gilkes, Senthold Asseng, Jim Dixon, Felicity Byrne, Mike Ewing, Dennis Van Gool, Louise Barton, Ralf Kiese, David Gatter, Klaus Butterbach-Bahl, Renee Buck, Christoph Hinz, Daniel Murphy, Cameron Weeks, Meredith Fairbanks, John Peirce, Brad Rayner, Sandy White, Paul Damon, Qifa Ma, Zed Rengel, Ed Barrett-Lennard, Meir Altman, Tracey M. Gianatti, Lindsay Bell, Ben Webb, Caroline Peek, Paul Sanford, Paul Blackwell, Glen Riethmuller, Darshan Sharma, Mike Collins, Frank D'Emden, David Hall, G. P. Manango, D. L. Steverson, Vanessa Stewart, Julie Roche, Peter Rutherford, Imma Farré, Ian Foster, Stephen Charles, Frances Hoyle, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Rob Sands, David Mccarthy, Paul Carmody, J. Russell, J. Eyres, G. Fosbery, A. Roe, Phil Nichols, Andrew Bathgate, Anne Wilkins

Crop Updates

This session covers forty papers from different authors:

1. Quality Assurance and industry stewardship, David Jeffries, Better Farm IQ Manager, Cooperative Bulk Handling

2. Sothis: Trifolium dasyurum (Eastern Star clover), A. Loi, B.J. Nutt and C.K. Revell, Department of Agriculture and Food

3. Poor performing patches of the paddock – to ameliorate or live with low yield? Yvette Oliver1, Michael Robertson1, Bill Bowden2, Kit Leake3and Ashley Bonser3, CSIRO Sustainable Ecosystems1, Department of Food and Agriculture2, Kellerberrin Farmer3

4. What evidence is there that …


Agenda: Water And Growth In The West, University Of Colorado Boulder. Natural Resources Law Center, The William And Flora Hewlett Foundation Jun 2000

Agenda: Water And Growth In The West, University Of Colorado Boulder. Natural Resources Law Center, The William And Flora Hewlett Foundation

Water and Growth in the West (Summer Conference, June 7-9)

1 v. (various pagings) : ill., maps ; 29 cm. + 1 CD-ROM (4 3/4 in.) + supplement (207 p. ; 29 x 24 cm.)

"Conference co-sponsor The William and Flora Hewlett Foundation."

Conference moderators included University of Colorado School of Law professors Gary C. Bryner, James N. Corbridge, Jr., David H. Getches, Douglas S. Kenney, Kathryn M. Mutz, Peter D. Nichols and Charles F. Wilkinson.

Accompanied by: CD-ROM (4 3/4 in.) and supplement (xiv, 140, [49] p.)

Includes bibliographical references

The event will cover a breadth of issues, including demographics and water-use trends, improved planning and efficient use, implementation …


A Search For Average, Extremes, And Runs Of Unusual Weather In Iowa, R. E. Carlson, D. P. Todey Jan 1997

A Search For Average, Extremes, And Runs Of Unusual Weather In Iowa, R. E. Carlson, D. P. Todey

Journal of the Iowa Academy of Science: JIAS

Temperature and precipitation during the past decade have exhibited wide variation throughout Iowa. Is this unusual? An attempt was made to answer this question by computing various statistical parameters that characterize variation in Iowa's long term climatic record. Absolute deviations were used to identify the most and least variable months and years since 1900. Overall, 1936 with a very cold winter and very warm summer was the least normal year. Runs of daily weather showed that heat and cold stress could often persist for more than 1 month. Runs of dry days were much longer than runs of wet days. …


Analysis Of An Iowa Aridity Index In Relationship To Climate And Crop Yield, Soumare Harouna, R. E. Carlson Jan 1994

Analysis Of An Iowa Aridity Index In Relationship To Climate And Crop Yield, Soumare Harouna, R. E. Carlson

Journal of the Iowa Academy of Science: JIAS

An aridity index and its components, temperature and precipitation, for the period from 1900 through April 1993 were defined and characterized. This index describes the anomalous behavior of both temperature and precipitation over time. Our intent was to examine climate variability in Iowa. Moving mean and standard deviations over various lengths of time were calculated from three time series. We found that these indices fluctuate considerably from year to year and from month to month. The lowest aridity index values occurred in the recent summer of 1992, and the highest occurred during the very drought-prone 1930s. The 12-month moving mean …


Iowa's Climate As Projected By The Global Climate Model Of The Goddard Institute For Space Studies For A Doubling Of Atmospheric Carbon Dioxide, E. S. Takle, S. Zhong Jan 1991

Iowa's Climate As Projected By The Global Climate Model Of The Goddard Institute For Space Studies For A Doubling Of Atmospheric Carbon Dioxide, E. S. Takle, S. Zhong

Journal of the Iowa Academy of Science: JIAS

Results of a global climate model that simulates climate under a doubling of atmospheric carbon dioxide (estimated to occur by the latter half of the twenty first century) have been interpolated to Iowa. Summer temperatures under such a doubling are projected to rise by 4 to 7°F (2.2 to 3.9°C) and winter temperatures by 10 to 11° (5.6 to 6.1°C). Estimates of space heating and cooling demands from these data suggest a 30 to 35% decrease in space heat demand and a 200 to 300% increase in space cooling demand. Temperature variability is projected to decrease. Precipitation estimates from global …


Climate Trends In Iowa, Richard E. Carlson Jan 1990

Climate Trends In Iowa, Richard E. Carlson

Journal of the Iowa Academy of Science: JIAS

Long-term trends for various weather elements are presented for the period 1900-1988. Summer and winter season, and annual air temperature patterns are statistically weak because of large inrerannual variability, but trends are evident. There was a general warming from 1900 until the 40's, with a leveling or slight cooling following. Since the mid-70's, a warming trend seems to be taking place, but this cannot be confirmed. Spring season air temperatures showed no trend except that the most recent 4 years (1985-1988) were decidedly warmer than normal. Winter season air temperatures showed a change in trend in the 30's, but the …