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Full-Text Articles in Physical Sciences and Mathematics

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

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

Plant and Soil Sciences Faculty Publications

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


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

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

Masters Theses & Specialist Projects

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


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

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

United States Geological Survey: Staff Publications

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


Agenda: Coping With Water Scarcity In River Basins Worldwide: Lessons Learned From Shared Experiences, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment Jun 2016

Agenda: Coping With Water Scarcity In River Basins Worldwide: Lessons Learned From Shared Experiences, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment

Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)

Water scarcity is increasingly dominating headlines throughout the world. In the southwestern USA, the looming water shortages on the Colorado River system and the unprecedented drought in California are garnering the greatest attention. Similar stories of scarcity and crisis can be found across the globe, suggesting an opportunity for sharing lessons and innovations. For example, the Colorado River and Australia's Murray-Darling Basin likely can share many lessons, as both systems were over-allocated, feature multiple jurisdictions, face similar climatic risks and drought stresses, and struggle to balance human demands with environmental needs. In this conference we cast our net broadly, exploring …


Twentieth-Century Warming Preserved In A Geladaindong Mountain Ice Core, Central Tibetan Plateau, Yulan Zhang, Shichang Kang, Bjorn Grigholm, Yongjun Zhang, Susan Kaspari, Uwe Morgenstern, Jiawen Ren, Dahe Qin, Paul A. Mayewski, Qianggong Zhang, Zhiyuan Cong, Mika Sillanpää, Margit Schwikowski, Feng Chen Mar 2016

Twentieth-Century Warming Preserved In A Geladaindong Mountain Ice Core, Central Tibetan Plateau, Yulan Zhang, Shichang Kang, Bjorn Grigholm, Yongjun Zhang, Susan Kaspari, Uwe Morgenstern, Jiawen Ren, Dahe Qin, Paul A. Mayewski, Qianggong Zhang, Zhiyuan Cong, Mika Sillanpää, Margit Schwikowski, Feng Chen

All Faculty Scholarship for the College of the Sciences

High-resolution δ18O records from a Geladaindong mountain ice core spanning the period 1477-1982 were used to investigate past temperature variations in the Yangtze River source region of the central Tibetan Plateau (TP). Annual ice-core δ18O records were positively correlated with temperature data from nearby meteorological stations, suggesting that the δ18O record represented the air temperature in the region. A generally increasing temperature trend over the past 500 years was identified, with amplified warming during the 20th century. A colder stage, spanning before the 1850s, was found to represent the Little Ice Age with colder …


Influence Of Sea Ice On Arctic Precipitation, Ben G. Kopec, Xiahong Feng, Fred A. Michel, Eric S. Posmentier Jan 2016

Influence Of Sea Ice On Arctic Precipitation, Ben G. Kopec, Xiahong Feng, Fred A. Michel, Eric S. Posmentier

Dartmouth Scholarship

Global climate is influenced by the Arctic hydrologic cycle, which is, in part, regulated by sea ice through its control on evaporation and precipitation. However, the quantitative link between precipitation and sea ice extent is poorly constrained. Here we present observational evidence for the response of precipitation to sea ice reduction and assess the sensitivity of the response. Changes in the proportion of moisture sourced from the Arctic with sea ice change in the Canadian Arctic and Greenland Sea regions over the past two decades are inferred from annually averaged deuterium excess (d-excess) measurements from six sites. Other influences on …


Assessing Drought Vulnerability Using A Socioecological Framework, Joel R. Brown, Doug Kluck, Chad Mcnutt, Michael J. Hayes Jan 2016

Assessing Drought Vulnerability Using A Socioecological Framework, Joel R. Brown, Doug Kluck, Chad Mcnutt, Michael J. Hayes

Drought Mitigation Center: Faculty Publications

Drought is a persistent problem on rangelands and adjusting management to respond appropriately is critical to both preserving natural resources and to maintaining financial viability. • We explore the value of using a structured assessment approach to determining both social and ecological vulnerability. • This approach allows for the identification of vulnerable ecosystems and business operations at regional and local scales as a basis for developing effective policies and programs.


Trade-Offs Between Three Forest Ecosystem Services Across The State Of New Hampshire, Usa: Timber, Carbon, And Albedo, David A. Lutz, Elizabeth A. Burakowski, Mackenzie B. Murphy, Mark E. Borsuk Jan 2016

Trade-Offs Between Three Forest Ecosystem Services Across The State Of New Hampshire, Usa: Timber, Carbon, And Albedo, David A. Lutz, Elizabeth A. Burakowski, Mackenzie B. Murphy, Mark E. Borsuk

Dartmouth Scholarship

Forests are more frequently being managed to store and sequester carbon for the purposes of climate change mitigation. Generally, this practice involves long-term conservation of intact mature forests and/or reductions in the frequency and intensity of timber harvests. However, incorporating the influence of forest surface albedo often suggests that long rotation lengths may not always be optimal in mitigating climate change in forests characterized by frequent snowfall. To address this, we investigated trade-offs between three ecosystem services: carbon storage, albedo-related radiative forcing, and timber provisioning. We calculated optimal rotation length at 498 diverse Forest Inventory and Analysis forest sites in …


Synergistic Effects Of Climate Change And Grazing On Net Primary Production Of Mongolian Grasslands, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Shufen Pan, Neil Pederson, Amy Hessl Jan 2016

Synergistic Effects Of Climate Change And Grazing On Net Primary Production Of Mongolian Grasslands, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Shufen Pan, Neil Pederson, Amy Hessl

Faculty & Staff Scholarship

In arid and semi-arid regions, grassland degradation has become a major environmental and economic problem, but little information is available on the response of grassland productivity to both climate change and grazing intensity. By developing a grazing module in a process-based ecosystem model, the dynamic land ecosystem model (DLEM), we explore the roles of climate change, elevated CO2, and varying grazing intensities in affecting aboveground net primary productivity (ANPP) across different grassland sites in Mongolia. Our results show that both growing season precipitation totals and average temperature exert important controls on annual ANPP across six sites over a precipitation gradient, …


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

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

United States Geological Survey: Staff Publications

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


Beyond Just Sea-Level Rise: Considering Macroclimatic Drivers Within Coastal Wetland Vulnerability Assessments To Climate Change, Michael J. Osland, Nicholas M. Enwright, Richard H. Day, Christopher A. Gabler, Camille L. Stagg, James B. Grace Jan 2016

Beyond Just Sea-Level Rise: Considering Macroclimatic Drivers Within Coastal Wetland Vulnerability Assessments To Climate Change, Michael J. Osland, Nicholas M. Enwright, Richard H. Day, Christopher A. Gabler, Camille L. Stagg, James B. Grace

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate change-related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would …


Carbon Uptake And Water Use In Woodlands And Forests In Southern Australia During An Extreme Heat Wave Event In The "Angry Summer" Of 2012/2013, Eva Van Gorsel, Sebastian Wolf, James Cleverly, Peter Isaac, Vanessa Haverd, Caecilia M. Ewenz, Stefan Arndt, Jason Beringer, Victor R. De Dios, Bradley John Evans, Anne Griebel, Lindsay B. Hutley, Trevor F. Keenan, Natascha Kljun, Craig Macfarlane, Wayne S. Meyer, Ian Mchugh, E. G. Pendall, Suzanne M. Prober, Richard P. Silberstein Jan 2016

Carbon Uptake And Water Use In Woodlands And Forests In Southern Australia During An Extreme Heat Wave Event In The "Angry Summer" Of 2012/2013, Eva Van Gorsel, Sebastian Wolf, James Cleverly, Peter Isaac, Vanessa Haverd, Caecilia M. Ewenz, Stefan Arndt, Jason Beringer, Victor R. De Dios, Bradley John Evans, Anne Griebel, Lindsay B. Hutley, Trevor F. Keenan, Natascha Kljun, Craig Macfarlane, Wayne S. Meyer, Ian Mchugh, E. G. Pendall, Suzanne M. Prober, Richard P. Silberstein

Research outputs 2014 to 2021

As a result of climate change warmer temperatures are projected through the 21st century and are already increasing above modelled predictions. Apart from increases in the mean, warm/hot temperature extremes are expected to become more prevalent in the future, along with an increase in the frequency of droughts. It is crucial to better understand the response of terrestrial ecosystems to such temperature extremes for predicting land-surface feedbacks in a changing climate. While land-surface feedbacks in drought conditions and during heat waves have been reported from Europe and the US, direct observations of the impact of such extremes on the carbon …