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Full-Text Articles in Climate

An Assessment Of Soil Erosion On Pemba Island Using The Universal Soil Loss Equation, Emily Gillispie Apr 2016

An Assessment Of Soil Erosion On Pemba Island Using The Universal Soil Loss Equation, Emily Gillispie

Independent Study Project (ISP) Collection

Healthy soil is necessary for maintaining agricultural productivity, which is the basis of the economy on Pemba Island, Tanzania. Soil erosion is a notable concern for subsidence-farming villages, as it reduces the agricultural potential of farmland through the loss of nutrients, organic matter, and depth of quality growing soil (Georhing, 2009). The island of Pemba is the perfect case study for soil erosion, as their economy is largely based in agriculture, and the combined hilly topography and monsoonal climate make it highly susceptible to soil erosion. Yet, Pemba’s main cash crops are clove and fruit trees, which have potential to …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- April 2016, Natalie A. Umphlett, Bill Sorensen, Jamie Lahowetz, Crystal J. Stiles Apr 2016

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- April 2016, Natalie A. Umphlett, Bill Sorensen, Jamie Lahowetz, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the interim director........................................1

Staff spotlight...........................1

Weather-Ready Nation Ambassador Program............2

Tribal work highlight..............2

Product highlight....................3

Partnership spotlight.............3

AWDN information.................4

Update on regional climate conditions..................................4

Outreach/engagement.........5

Recent and upcoming travel and activities.............................6


Crop Modeling For Assessing And Mitigating The Impacts Of Extreme Climatic Events On The Us Agriculture System, Zhenong Jin Apr 2016

Crop Modeling For Assessing And Mitigating The Impacts Of Extreme Climatic Events On The Us Agriculture System, Zhenong Jin

Open Access Dissertations

The US agriculture system is the world’s largest producer of maize and soybean, and typically supplies more than one-third of their global trading. Nearly 90% of the US maize and soybean production is rainfed, thus is susceptible to climate change stressors such as heat waves and droughts. Process-based crop and cropping system models are important tools for climate change impact assessments and risk management. As data- science is becoming a new frontier for agriculture growth, the incoming decade calls for operational platforms that use hyper-local growth monitoring, high-resolution real-time weather and satellite data assimilation and cropping system modeling to help …


Droughtscape, Spring 2016, National Drought Mitigation Center Apr 2016

Droughtscape, Spring 2016, National Drought Mitigation Center

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

Contents

Director’s report

First quarter drought summary

First quarter drought impacts

Drought Risk Management Research Center

Kenyan official visits

DrIVER eyes forecasting

Drought scenario exercise

Student projects

Drought tournament

Response and recovery guide

Drought Portal

Network of drought observers

Caribbean “writeshops”

Communications staff grows


The Wais Divide Deep Ice Core Wd2014 Chronology – Part 2: Annual-Layer Counting (0–31 Ka Bp), Michael Sigl, Tyler J. Fudge, Mai Winstrup, Jihong Cole-Dai, David Ferris Mar 2016

The Wais Divide Deep Ice Core Wd2014 Chronology – Part 2: Annual-Layer Counting (0–31 Ka Bp), Michael Sigl, Tyler J. Fudge, Mai Winstrup, Jihong Cole-Dai, David Ferris

Dartmouth Scholarship

We present the WD2014 chronology for the upper part (0–2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposition of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cosmogenic isotope records of Be from WAIS Divide and C for IntCal13 demonstrated …


Mapping Irrigated And Rainfed Wheat Areas Using Multi-Temporal Satellite Data, Ning Jin, Bo Tao, Wei Ren, Meichen Feng, Rui Sun, Liang He, Wei Zhuang, Qiang Yu Mar 2016

Mapping Irrigated And Rainfed Wheat Areas Using Multi-Temporal Satellite Data, Ning Jin, Bo Tao, Wei Ren, Meichen Feng, Rui Sun, Liang He, Wei Zhuang, Qiang Yu

Plant and Soil Sciences Faculty Publications

Irrigation is crucial to agriculture in arid and semi-arid areas and significantly contributes to crop development, food diversity and the sustainability of agro-ecosystems. For a specific crop, the separation of its irrigated and rainfed areas is difficult, because their phenology is similar and therefore less distinguishable, especially when there are phenology shifts due to various factors, such as elevation and latitude. In this study, we present a simple, but robust method to map irrigated and rainfed wheat areas in a semi-arid region of China. We used the Normalized Difference Vegetation Index (NDVI) at a 30 × 30 m spatial resolution …


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 …


Umphlett Qci March 2016, Natalie Umphlett Mar 2016

Umphlett Qci March 2016, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Vegetation Conditions

Early Signs of Spring

Winter Wheat Breaks Dormancy

3-Month Precipitation and Temperature Outlooks

Percent of Average Precipitation: Strong El Niños


Identifying The Relationships Of Climate And Physiological Responses Of A Beech Forest Using The Standardised Recipitation Index: A Case Study For Slovakia, Jaroslav Vido, Katarína Střelcová, Paulína Nalevanková, Adriana Leštianska, Radoslav Kandrík, Alena Pástorová, Jaroslav Škvarenina, Tsegaye Tadesse Feb 2016

Identifying The Relationships Of Climate And Physiological Responses Of A Beech Forest Using The Standardised Recipitation Index: A Case Study For Slovakia, Jaroslav Vido, Katarína Střelcová, Paulína Nalevanková, Adriana Leštianska, Radoslav Kandrík, Alena Pástorová, Jaroslav Škvarenina, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

The paper presents relationship between the Standardised Precipitation Index (SPI) and physiological responses of individual trees in a beech stand using an example of an experimental plot in Bienska valley (Zvolen, Slovakia). SPI is a widely used tool for monitoring both short-term and long-term droughts, and for the assessments of drought impacts on agriculture. Due to the complex ecosystem bonds, monitoring of drought in forests often requires a sophisticated technological approach. The aim of the paper was to correlate the SPI on the physiological responses of trees that were recorded during the performed physiological research (sap flow, and stem circumference …


Propagation Of Drought: From Meteorological Drought To Agricultural And Hydrological Drought, Wen Wang, Maurits W. Ertsen, Mark D. Svoboda, Mohsin Hafeez Jan 2016

Propagation Of Drought: From Meteorological Drought To Agricultural And Hydrological Drought, Wen Wang, Maurits W. Ertsen, Mark D. Svoboda, Mohsin Hafeez

National Drought Mitigation Center: Faculty Publications

Drought is a hazard that occurs everywhere in the world (both in dry and in wet areas). Despite the controversy regarding drought changes in the last decades [1–3], increases in drought intensity are clearly identified in some areas [4] and it is believed that although increased heating from global warming may not directly cause droughts, it is expected that when droughts occur, they are likely to set in quicker and be more intense [5].

Throughout its history, China has frequently suffered from drought disasters due to its monsoon climate and was regularly hit hard by droughts over the last decades. …


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 …


Stakeholder Coinquiries On Drought Impacts, Monitoring And Early Warning Systems, Kevin Collins, Jamie Hannaford, Mark D. Svoboda, Cody L. Knutson, Nicole A. Wall, Tonya K. Bernadt, Neville Crossman, Ian Overton, Mike Acreman, Sophie Bachmair, Kerstin Stahl Jan 2016

Stakeholder Coinquiries On Drought Impacts, Monitoring And Early Warning Systems, Kevin Collins, Jamie Hannaford, Mark D. Svoboda, Cody L. Knutson, Nicole A. Wall, Tonya K. Bernadt, Neville Crossman, Ian Overton, Mike Acreman, Sophie Bachmair, Kerstin Stahl

National Drought Mitigation Center: Faculty Publications

The goal of the DrIVER (Drought Impacts: Vulnerability thresholds in monitoring and Early-warning Research) research project is to understand the links between natural (hydro-meteorological) drought and ecological response and socio-economic impacts to aid in developing enhanced drought early warning systems (DEWS). Three stakeholder workshops were convened in the USA, UK and Australia. The USA water supply case study engaged 27 community water suppliers and state, federal and private advisors in the Neuse and Cape Fear River basins in North Carolina. The UK workshop involved 34 national and regional stakeholders across the water supply, environmental regulation, agriculture, energy and health sectors. …


Handbook Of Drought Indicators And Indices, Mark Svoboda, Brian Fuchs, Integrated Drought Management Programme (Idmp) Jan 2016

Handbook Of Drought Indicators And Indices, Mark Svoboda, Brian Fuchs, Integrated Drought Management Programme (Idmp)

National Drought Mitigation Center: Faculty Publications

The purpose of this handbook is to cover some of the most commonly used drought indicators/indices that are being applied across drought-prone regions, with the goal of advancing monitoring, early warning and information delivery systems in support of risk-based drought management policies and preparedness plans. These concepts and indicators/indices are outlined below in what is considered to be a living document that will evolve and integrate new indicators and indices as they come to light and are applied in the future. The handbook is aimed at those who want to generate indicators and indices themselves, as well as for those …


From Grassroots To National Alliance: The Emerging Trajectory For Landowner Prescribed Burn Associations, John R. Weir, Dirac L. Twidwell, Carissa L. Wonkka Jan 2016

From Grassroots To National Alliance: The Emerging Trajectory For Landowner Prescribed Burn Associations, John R. Weir, Dirac L. Twidwell, Carissa L. Wonkka

National Drought Mitigation Center: Faculty Publications

• Due to woody plant encroachment and seeing the need for fire on their lands, private landowners throughout the southern Great Plains have started forming prescribed burn associations (PBA) to assist each other with conducting prescribed fires. • Members of PBAs work together by pooling equipment and other resources, organizing training opportunities, and assisting with prescribed burns on each other’s properties, while teaching upcoming generations and inexperienced members the value of fire in grassland conservation and how to safely use it. • There are over 50 PBAs working in the southern Great Plains. As the number of PBAs has grown …


Rangeland Responses To Predicted Increases In Drought Extremity, David D. Breshears, Alan K. Knapp, Darin J. Law, Melinda D. Smith, Dirac L. Twidwell, Carissa L. Wonkka Jan 2016

Rangeland Responses To Predicted Increases In Drought Extremity, David D. Breshears, Alan K. Knapp, Darin J. Law, Melinda D. Smith, Dirac L. Twidwell, Carissa L. Wonkka

National Drought Mitigation Center: Faculty Publications

Rangeland managers actively focus on the potential to induce a shift in a site to an alternative state, but predicted changes in climate, particularly the likelihood of more extreme drought, necessitate reevaluating risks for alternative states. • Rangelands will differ in their susceptibility to undergo state changes due to climate change in general and for droughts of the future, in particular, which may be hotter. • Trees, shrubs, and grasses are expected to differ in their sensitivity to drought, with trees likely being most sensitive; this affects the likelihood for state changes in grasslands, shrublands, woodlands, and savannas. • Considering …


Climate-Relevant Land Use And Land Cover Change Policies, Rezaul Mahmood, Roger A. Pielke Sr., Clive Mcalpine Jan 2016

Climate-Relevant Land Use And Land Cover Change Policies, Rezaul Mahmood, Roger A. Pielke Sr., Clive Mcalpine

High Plains Regional Climate Center: Staff Publications

Both observational and modeling studies clearly demonstrate that land-use and land-cover change (LULCC) play an important biogeophysical and biogeochemical role in the climate system from the landscape to regional and even continental scales. Without comprehensively considering these impacts, an adequate response to the threats posed by human intervention into the climate system will not be adequate. Public policy plays an important role in shaping local- to national-scale land-use practices. An array of national policies has been developed to influence the nature and spatial extent of LULCC. Observational evidence suggests that these policies, in addition to international trade treaties and protocols, …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center: January 2016, Martha Shulski, Natalie Umphlett, Crystal J. Stiles Jan 2016

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center: January 2016, Martha Shulski, Natalie Umphlett, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the director........................................1

Staff spotlight...........................1

HPRCC staff changes..............2

Product highlight....................2

Research highlight..................2

Partnership spotlight.............3

AWDN information.................4

Update on regional climate conditions..................................4

Outreach/engagement.........5

Recent and upcoming travel and activities.............................6


Drought And Health In The Context Of Public Engagement, Nicole Wall, Michael Hayes Jan 2016

Drought And Health In The Context Of Public Engagement, Nicole Wall, Michael Hayes

National Drought Mitigation Center: Faculty Publications

Droughts have profoundly affected societies around the world from the earliest beginnings. A recent estimate from the Centre for Research on the Epidemiology of Disasters (CRED) claims that more than 1 billion people have been affected by drought during the twenty-year period between 1994 and 2013. Because of the characteristics of drought, drought impacts are often difficult to identify and quantify, and this is especially true with public health-oriented drought consequences, including those resulting from low water quantities, poor water quality, mental health and stress, dust and windblown agents, and wildlife intrusion. However, when officials emphasize adopting a proactive risk …


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

National 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.


Support For Drought Response And Community Preparedness: Filling The Gaps Between Plans And Action, Kelly Helm Smith, Crystal J. Stiles, Michael Hayes, Christopher Carparelli Jan 2016

Support For Drought Response And Community Preparedness: Filling The Gaps Between Plans And Action, Kelly Helm Smith, Crystal J. Stiles, Michael Hayes, Christopher Carparelli

High Plains Regional Climate Center: Staff Publications

This chapter examines which levels of government handle various aspects of drought, as well as interactions between levels of government, providing examples from states across the western United States. It also takes a look at aspects of drought that fall outside traditional lines of authority and disciplinary boundaries. As part of a discussion on how states support local drought response, the chapter details and contrasts how California and Colorado track public water supply restrictions, and describes Colorado’s process for incorporating input from river basins across the state into its water plan. Case studies focus on drought planning in the Klamath …


Modelling The Response Of Ice Shelf Basal Melting To Different Ocean Cavity Environmental Regimes, David E. Gwyther, Eva A. Cougnon, Benjamin K. Galton-Fenzi, Jason L. Roberts, John R. Hunter, Michael S. Dinniman Jan 2016

Modelling The Response Of Ice Shelf Basal Melting To Different Ocean Cavity Environmental Regimes, David E. Gwyther, Eva A. Cougnon, Benjamin K. Galton-Fenzi, Jason L. Roberts, John R. Hunter, Michael S. Dinniman

CCPO Publications

We present simulation results from a version of the Regional Ocean Modeling System modified for ice shelf/ocean interaction, including the parameterisation of basal melting by molecular diffusion alone. Simulations investigate the differences in melting for an idealised ice shelf experiencing a range of cold to hot ocean cavity conditions. Both the pattern of melt and the location of maximum melt shift due to changes in the buoyancy-driven circulation, in a different way to previous studies. Tidal forcing increases both the circulation strength and melting, with the strongest impact on the cold cavity case. Our results highlight the importance of including …


Droughtscape, Winter 2016, Kelly Smith Jan 2016

Droughtscape, Winter 2016, Kelly Smith

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

Contents

Director’s column

California drought FAQ

October-December 2015 drought

October-December 2015 impacts

2015 drought impacts in review

NDMC hiring geospatial analyst

CA drought exposes social vulnerability

UA helps Arizona ranchers, Forest Service work together

NDMC and partners help southern Plains ranchers manage drought

Chickasaw ranching workshop


Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi Jan 2016

Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi

Theses and Dissertations (Comprehensive)

Peatlands have a unique biogeochemical function, characterized by an imbalance between the rates of biomass accumulation and decomposition. These characteristics facilitate the ability of peatlands to support the sequestration of nutrients and carbon. In disturbed peatlands, these functions are compromised. Thus, reclamation targets amongst other key functions, the recovery of biogeochemical functioning. These functions could serve as a measure of recovery to conditions that are present in natural analogues. This thesis examines the recovery of microbially-mediated nutrient transformation processes in a fen peatland that was constructed on a post-mining landscape in the Athabasca oil sands region, Fort McMurray, Alberta. The …


Assessing The Impact Of Vertical Land Motion On Twentieth Century Global Mean Sea Level Estimates, B. D. Hamlington, P. Thompson, W. C. Hammond, G. Blewitt, R. D. Ray Jan 2016

Assessing The Impact Of Vertical Land Motion On Twentieth Century Global Mean Sea Level Estimates, B. D. Hamlington, P. Thompson, W. C. Hammond, G. Blewitt, R. D. Ray

CCPO Publications

Near-global and continuous measurements from satellite altimetry have provided accurate estimates of global mean sea level in the past two decades. Extending these estimates further into the past is a challenge using the historical tide gauge records. Not only is sampling nonuniform in both space and time, but tide gauges are also affected by vertical land motion (VLM) that creates a relative sea level change not representative of ocean variability. To allow for comparisons to the satellite altimetry estimated global mean sea level (GMSL), typically the tide gauges are corrected using glacial isostatic adjustment (GIA) models. This approach, however, does …


Mechanism Of Seasonal Arctic Sea Ice Evolution And Arctic Amplification, Kwang-Yul Kim, Benjamin D. Hamlington, Hanna Na, Jinju Kim Jan 2016

Mechanism Of Seasonal Arctic Sea Ice Evolution And Arctic Amplification, Kwang-Yul Kim, Benjamin D. Hamlington, Hanna Na, Jinju Kim

CCPO Publications

Sea ice loss is proposed as a primary reason for the Arctic amplification, although the physical mechanism of the Arctic amplification and its connection with sea ice melting is still in debate. In the present study, monthly ERA-Interim reanalysis data are analyzed via cyclostationary empirical orthogonal function analysis to understand the seasonal mechanism of sea ice loss in the Arctic Ocean and the Arctic amplification. While sea ice loss is widespread over much of the perimeter of the Arctic Ocean in summer, sea ice remains thin in winter only in the Barents-Kara seas. Excessive turbulent heat flux through the sea …


Assessing The Evolution Of Soil Moisture And Vegetation Conditions During The 2012 United States Flash Drought, Jason A. Otkin, Martha C. Anderson, Christopher R. Hain, Mark D. Svoboda, David K. Johnson, Richard Mueller, Tsegaye Tadesse, Brian D. Wardlow, Jesslyn Brown Jan 2016

Assessing The Evolution Of Soil Moisture And Vegetation Conditions During The 2012 United States Flash Drought, Jason A. Otkin, Martha C. Anderson, Christopher R. Hain, Mark D. Svoboda, David K. Johnson, Richard Mueller, Tsegaye Tadesse, Brian D. Wardlow, Jesslyn Brown

National Drought Mitigation Center: Faculty Publications

This study examines the evolution of several model-based and satellite-derived drought metrics sensitive to soil moisture and vegetation conditions during the extreme flash drought event that impacted major agricultural areas across the central U.S. during 2012. Standardized anomalies from the remote sensing based Evaporative Stress Index (ESI) and Vegetation Drought Response Index (VegDRI) and soil moisture anomalies from the North American Land Data Assimilation System (NLDAS) are compared to the United States Drought Monitor (USDM), surface meteorological conditions, and crop and soil moisture data compiled by the National Agricultural Statistics Service (NASS).

Overall, the results show that rapid decreases in …


The Implications Of Climate Change For Nebraska: Summary Report Of Sector-Based Roundtable Discussions, Donald A. Wilhite, Kimberly Morrow Jan 2016

The Implications Of Climate Change For Nebraska: Summary Report Of Sector-Based Roundtable Discussions, Donald A. Wilhite, Kimberly Morrow

National Drought Mitigation Center: Faculty Publications

This report is the result of the work of many individuals that contributed to the success of the series of eight sector-based roundtable events that were held in September and October of 2015. First and foremost, we would like to thank the organizers and the organizations they represent for their leadership in bringing together a diverse set of key stakeholders to discuss the implications of climate change on their sector. It was such a pleasure to work with such a dedicated group of individuals. Second, we would like to thank the more than 350 people who participated in these discussions …


New Tools For Assessing Drought Conditions For Rangeland Management, Cody Knutson, Brian Fuchs Jan 2016

New Tools For Assessing Drought Conditions For Rangeland Management, Cody Knutson, Brian Fuchs

National Drought Mitigation Center: Faculty Publications

Historical drought assessment and ongoingmonitoring is essential for understanding past drought occurrence, the relationships between past drought and its impacts, and for triggering action during current drought events. • A variety of new products have recently been developed to better monitor drought conditions and assess past occurrences at the local scale. • A growing number of resources are available to assist rangeland managers to develop a monitoring system and incorporate it into a drought management plan.


Optical Properties And Bioavailability Of Dissolved Organic Matter Along A Flow-Path Continuum From Soil Pore Waters To The Kolyma River Mainstem, East Siberia, Karen E. Frey, William V. Sobczak, Paul J. Mann, Robert M. Holmes Jan 2016

Optical Properties And Bioavailability Of Dissolved Organic Matter Along A Flow-Path Continuum From Soil Pore Waters To The Kolyma River Mainstem, East Siberia, Karen E. Frey, William V. Sobczak, Paul J. Mann, Robert M. Holmes

Geography

The Kolyma River in northeast Siberia is among the six largest Arctic rivers and drains a region underlain by vast deposits of Holocene-aged peat and Pleistocene-aged loess known as yedoma, most of which is currently stored in ice-rich permafrost throughout the region. These peat and yedoma deposits are important sources of dissolved organic matter (DOM) to inland waters that in turn play a significant role in the transport and ultimate remineralization of organic carbon to CO2 and CH4 along the terrestrial flow-path continuum. The turnover and fate of terrigenous DOM during offshore transport largely depends upon the composition and amount …


Evidence For The Drainage Of A Superglacial Lake As The Source Of Seismic Waves Recorded At A Regional Distance, Erik J. Orantes Jan 2016

Evidence For The Drainage Of A Superglacial Lake As The Source Of Seismic Waves Recorded At A Regional Distance, Erik J. Orantes

Dissertations and Theses

Surface melting during the summer leads to the formation of lakes on the Greenland Ice Sheet surface, known as supraglacial lakes. Some of these lakes drain through cracks in their beds and release the water into the ice sheet. Previous studies suggest that some of the water reaches the bedrock, enabling basal sliding, which could potentially increase glacial discharge (Sundal et al., 2009). Das et al. (2008) showed that supraglacial lake drainage can be accompanied by seismic activity, but little work has been done on the regional detection of such waves. The present study analyzes seismic data for the period …