Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 301 - 330 of 407

Full-Text Articles in Atmospheric Sciences

The Influence Of Soil Organic Matter Stabilization Mechanisms On Carbon Mean Residence Time Within Various Ecosystems In The United States, Vicky Lynn Giese, Kate Heckman Phd Aug 2013

The Influence Of Soil Organic Matter Stabilization Mechanisms On Carbon Mean Residence Time Within Various Ecosystems In The United States, Vicky Lynn Giese, Kate Heckman Phd

STAR Program Research Presentations

Some terrestrial ecosystems and soils serve as carbon sinks, partially offsetting rising atmospheric CO2 levels. Physiochemical mechanisms of soil organic matter (SOM) stabilization affect how carbon stocks respond to global warming. In order to clarify the variance in SOM stabilization mechanisms across different soil types, SOM abundance, distribution and mean residence time (MRT) were compared for thirty-two soil samples from six ecosystems across the United States. Soils were previously described, collected and archived by the United States Geological Survey. Samples were processed by LLNL at the Center for Accelerator Mass Spectrometry (CAMS) using density fractionation to separate particulate organics …


Climate Change On The Prairie: A Basic Guide To Climate Change In The High Plains Region - Update, Lincoln, Ne Aug 2013

Climate Change On The Prairie: A Basic Guide To Climate Change In The High Plains Region - Update, Lincoln, Ne

High Plains Regional Climate Center: Staff Publications

Global Climate Change

Climate Change in the United States

Historical Climate Trends in the High Plains Region

Historical Climate Trends in the High Plains Region

High Plains Region Update: 2010-2012

New Tool: Climate Impact Reporter

Climate Change Projections and Possible Impacts

Climate Change Projections and Possible Impacts


Droughtscape, Summer 2013, National Drought Mitigation Center Jul 2013

Droughtscape, Summer 2013, National Drought Mitigation Center

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

Contents

Director’s report

July 25 webinar: Drought management database, NIDIS update

Republican River Basin workshops July 31, August 1

Summer climate outlook, spring summary

Spring impacts: wildfire, water, agriculture and business

Data help managers assess Nebraska groundwater declines after drought of 2012

Tadesse helps Mexico with Veg-DRI concept

Visiting scholar explores remote sensing of drought in forests

U.S. Drought Monitor Forum photo recap, details online

Workshop helps New Mexico ranchers cope with drought

Alabama’s new drought plan

National Drought Forum report

Drought Impacts Community of Practice report


Discontinuities And Alfvenic Fluctuations In The Solar Wind, G. Paschmann, S. Haaland, B. Sonnerup, T. Knetter May 2013

Discontinuities And Alfvenic Fluctuations In The Solar Wind, G. Paschmann, S. Haaland, B. Sonnerup, T. Knetter

Dartmouth Scholarship

We examine the Alfvenicity of a set of 188 solar wind directional discontinuities (DDs) identified in the Cluster data from 2003 by Knetter (2005), with the objective of separating rotational discontinuities (RDs) from tangential ones (TDs). The DDs occurred over the full range of solar wind velocities and magnetic shear angles. By performing the Walen test in the de Hoffmann–Teller (HT) frame, we show that 77 of the 127 crossings for which a good HT frame was found had plasma flow speeds exceeding 80 % of the Alfven speed at an average angular deviation of 7.7◦; 33 cases had speeds …


Droughtscape, Spring 2013, National Drought Mitigation Center Apr 2013

Droughtscape, Spring 2013, National Drought Mitigation Center

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

Contents

Director’s report

First quarter climate summary and outlook

Impacts: Crop indemnities set records in 2012; water conflicts escalating

International meeting recommends countries have drought policies

NDMC plays key role in international drought policy meeting

EDEN and VOAD guide helps build community drought capacity

Svoboda, other experts and policymakers focus on food and water security

New Mexico ranching workshop set for May 29 in Socorro

Ranch planning updates: archived webinars, new publications

Tune in to the US Drought Monitor Forum, April 16-18

Archived webinar looks at using drought simulations in planning

CoCoRaHS WxTalk on drought


On The Lack Of Stratospheric Dynamical Variability In Low‐Top Versions Of The Cmip5 Models, Andrew J. Charlton-Perez, Mark P. Baldwin, Thomas Birner, Robert X. Black, Amy H. Butler, Natalia Calvo, Nicholas A. Davis, Edwin P. Gerber, Nathan Gillett, Steven Hardiman, Junsu Kim, Kirsten Krüger, Yun-Young Lee, Elisa Manzini, Brent A. Mcdaniel, Lorenzo Polvani, Thomas Reichler, Tiffany A. Shaw, Michael Sigmond, Seok-Woo Son, Matthew Toohey, Laura Wilcox, Shigeo Yoden, Bo Christiansen, François Lott, Drew Shindell, Seiji Yukimoto, Shingo Watanabe Mar 2013

On The Lack Of Stratospheric Dynamical Variability In Low‐Top Versions Of The Cmip5 Models, Andrew J. Charlton-Perez, Mark P. Baldwin, Thomas Birner, Robert X. Black, Amy H. Butler, Natalia Calvo, Nicholas A. Davis, Edwin P. Gerber, Nathan Gillett, Steven Hardiman, Junsu Kim, Kirsten Krüger, Yun-Young Lee, Elisa Manzini, Brent A. Mcdaniel, Lorenzo Polvani, Thomas Reichler, Tiffany A. Shaw, Michael Sigmond, Seok-Woo Son, Matthew Toohey, Laura Wilcox, Shigeo Yoden, Bo Christiansen, François Lott, Drew Shindell, Seiji Yukimoto, Shingo Watanabe

Faculty Articles

We describe the main differences in simulations of stratospheric climate and variability by models within the fifth Coupled Model Intercomparison Project (CMIP5) that have a model top above the stratopause and relatively fine stratospheric vertical resolution (high-top), and those that have a model top below the stratopause (low-top). Although the simulation of mean stratospheric climate by the two model ensembles is similar, the low-top model ensemble has very weak stratospheric variability on daily and interannual time scales. The frequency of major sudden stratospheric warming events is strongly underestimated by the low-top models with less than half the frequency of events …


Estimating Greenhouse Gas Emissions From A Waste Lagoon, Arturo I. Quintanar, Rezaul Mamood, Nanh Lovanh, Justin M. Rawley, Evi Becerra-Acosta, John H. Loughrin Jan 2013

Estimating Greenhouse Gas Emissions From A Waste Lagoon, Arturo I. Quintanar, Rezaul Mamood, Nanh Lovanh, Justin M. Rawley, Evi Becerra-Acosta, John H. Loughrin

High Plains Regional Climate Center: Staff Publications

A cost-effective approach was used to investigate the relationship between emission of the greenhouse gases (GHG), namely, CO2, CH4, and N2O and energy fluxes from a swine waste lagoon. Energy fluxes were calculated using the Penman method. The energy fluxes showed a diurnal pattern as expected of such fluxes. We found that air temperature and latent energy, lagoon surface temperature and solar radiation, as well as air temperature and wind speed can be used to predict for CO2, CH4, and N2O emissions, respectively. Comparison of observed and predicted …


Regional Climate Trends And Scenarios For The U.S. National Climate Assessment Part 4. Climate Of The U.S. Great Plains, Kenneth E. Kunkel, Laura E. Stevens, Scott E. Stevens, Liqiang Sun, Emily Janssen, Donald Wuebbles, Michael C. Kruk, Devin Thomas, Martha Shulski, Natalie A. Umphlett, Kenneth G. Hubbard, Kevin Robbins, Luigi Romolo, Adnan Akyuz, Tapan B. Pathak, Tony R. Bergantino, J. Greg Dobson Jan 2013

Regional Climate Trends And Scenarios For The U.S. National Climate Assessment Part 4. Climate Of The U.S. Great Plains, Kenneth E. Kunkel, Laura E. Stevens, Scott E. Stevens, Liqiang Sun, Emily Janssen, Donald Wuebbles, Michael C. Kruk, Devin Thomas, Martha Shulski, Natalie A. Umphlett, Kenneth G. Hubbard, Kevin Robbins, Luigi Romolo, Adnan Akyuz, Tapan B. Pathak, Tony R. Bergantino, J. Greg Dobson

High Plains Regional Climate Center: Staff Publications

This document is one of series of regional climate descriptions designed to provide input that can be used in the development of the National Climate Assessment (NCA). As part of a sustained assessment approach, it is intended that these documents will be updated as new and well-vetted model results are available and as new climate scenario needs become clear. It is also hoped that these documents (and associated data and resources) are of direct benefit to decision makers and communities seeking to use this information in developing adaptation plans.

There are nine reports in this series, one each for eight …


Droughtscape, Winter 2013, Kelly Smith Jan 2013

Droughtscape, Winter 2013, Kelly Smith

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

Contents

Director’s report

Climatological overview of drought in 2012

Climatological overview of drought, October-December 2012

Impacts of drought in 2012

Drought planning webinars scheduled for ranch advisors

UNL honors NDMC for exceptional service

Report from the emerging community of drought planners

Feb. 6 webinar on drought simulations

Climate Masters course starting

Climate Change in the Midwest book includes drought

Video highlights from coverage of drought of 2012

U.S. Drought Monitor Forum 2013

UN’s High Level Meeting on National Drought Policy

NDMC collaboration with India, Czech Republic


Climate Change: What Does It Mean For Nebraska?, Martha D. Shulski, Natalie A. Umphlett, Tapan B. Pathak, Kenneth G. Hubbard Jan 2013

Climate Change: What Does It Mean For Nebraska?, Martha D. Shulski, Natalie A. Umphlett, Tapan B. Pathak, Kenneth G. Hubbard

High Plains Regional Climate Center: Staff Publications

Because Nebraska’s location on the North American continent is far removed from large bodies of water, Nebraskans experience a strong continental type climate. As such, residents do not benefit from the moderating influence of the ocean, and temperatures can have wide swings from day to day and season to season. Typical characteristics for a continental climate at this latitude are large temperature variability with warm summers dominated by convective thunderstorms, and cold winters influenced by snow and wind from mid-latitude cyclones.


Cave Ventilation Is Influenced By Variations In The Co2-Dependent Virtual Temperature, Enrique P. Sánchez-Cañete, Penélope Serrano-Ortiz, Francisco Domingo, Andrew S. Kowalski Jan 2013

Cave Ventilation Is Influenced By Variations In The Co2-Dependent Virtual Temperature, Enrique P. Sánchez-Cañete, Penélope Serrano-Ortiz, Francisco Domingo, Andrew S. Kowalski

International Journal of Speleology

Dynamics and drivers of ventilation in caves are of growing interest for different fields of science. Accumulated CO2 in caves can be exchanged with the atmosphere, modifying the internal CO2 content, affecting stalagmite growth rates, deteriorating rupestrian paintings or creating new minerals. Current estimates of cave ventilation neglect the role of high CO2 concentrations in determining air density – approximated via the virtual temperature (Tv) –, affecting buoyancy and therefore the release or storage of CO2. Here we try to improve knowledge and understanding of cave ventilation through the use of T …


Interactions Between African Easterly Waves And Moist Convection, Matthew Adam Janiga Jan 2013

Interactions Between African Easterly Waves And Moist Convection, Matthew Adam Janiga

Legacy Theses & Dissertations (2009 - 2024)

African easterly waves (AEWs) over tropical Africa and the East Atlantic influence and are themselves influenced by moist convection. Data from the Tropical Rainfall Measuring Mission (TRMM) satellite, reanalyses, and in-situ observations are used to examine both directions of this two-way interaction.


Black Carbon Measurements Of Snow And Ice Using The Single Particle Soot Photometer: Method Development And An Ad 1852-1999 Record Of Atmospheric Black Carbon From A Mount Logan Ice Core, James Andrew Menking Jan 2013

Black Carbon Measurements Of Snow And Ice Using The Single Particle Soot Photometer: Method Development And An Ad 1852-1999 Record Of Atmospheric Black Carbon From A Mount Logan Ice Core, James Andrew Menking

All Master's Theses

Black carbon (BC), produced by the combustion of fossil and biofuels, warms the climate by absorbing solar radiation when in the atmosphere and by reducing the albedo of snow and ice when deposited. Measuring BC in snow and ice is important for estimating albedo reduction and developing historical records of BC concentration. Experiments were conducted to further develop a method for measuring BC in snow and ice using the Single Particle Soot Photometer (SP2). Results suggest the optimal procedures for sample storage, treatment, and nebulization, and analysis and calibration of BC concentrations measured using the SP2 coupled to a CETAC …


Carbon Farming In Wa, Department Of Agriculture And Food, Western Australia, Department Of Regional Development And Lands, Western Australia Jan 2013

Carbon Farming In Wa, Department Of Agriculture And Food, Western Australia, Department Of Regional Development And Lands, Western Australia

Natural resources published reports

Fact sheets:

1. Applying biochar to improve soil quality and crop productivity

2. Reducing methane emissions from cattle using feed additives

3. Cattle breeding for lower greenhouse gas emissions

4. Managing genetic codes to reduce methane emissions from cattle

5. Managing pastures and stocking rate to reduce methane emissions from cattle

6. Claying as a method of increasing soil carbon content

7. Green and brown manuring as part of carbon farming

8. Permanent environmental plantings to earn carbon credits

9. Nitrous oxide emissions from agricultural soils

10. Sheep genetics in methane reduction

11. Managing sheep pastures to reduce methane production …


2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl Dec 2012

2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study was to determine the moisture source of winter precipitation in the central Great Basin for the past 2000 years, and to elucidate the role of Pacific Ocean and North American climate variability modes in driving observed droughts of the region around the Medieval Climatic Anomaly (MCA, ~900-1300 CE). Here a high resolution (~2-4 year) precisely dated moisture source reconstruction is presented from the δ18O values of speleothem LC-1 collected from Leviathan Cave in central Nevada, which reveals significant δ18O variability. I attribute the δ18O variability to changes in winter-season moisture circulation over the past 2000 …


Droughtscape, Fall 2012, National Drought Mitigation Center Oct 2012

Droughtscape, Fall 2012, National Drought Mitigation Center

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

Contents

Director’s report

Updated resources

Drought outlook and review

2012 and past droughters

Summer impacts summary

Urban planners and drought

USDM wins CLEAN seal

Meixiu Yu's Chinese SPEI

Ethiopian project

Mexican VegDRI

Drought monitor sculpture


Retrieval Of Sub-Pixel-Based Fire Intensity And Its Application For Characterizing Smoke Injection Heights And Fire Weather In North America, David Peterson Sep 2012

Retrieval Of Sub-Pixel-Based Fire Intensity And Its Application For Characterizing Smoke Injection Heights And Fire Weather In North America, David Peterson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

For over two decades, satellite sensors have provided the locations of global fire activity with ever-increasing accuracy. However, the ability to measure fire intensity, know as fire radiative power (FRP), and its potential relationships to meteorology and smoke plume injection heights, are currently limited by the pixel resolution. This dissertation describes the development of a new, sub-pixel-based FRP calculation (FRPf) for fire pixels detected by the MODerate Resolution Imaging Spectroradiometer (MODIS) fire detection algorithm (Collection 5), which is subsequently applied to several large wildfire events in North America. The methodology inherits an earlier bi-spectral algorithm for retrieving sub-pixel …


Accuracy Assessment Of Aqua-Modis Aerosol Optical Depth Over Coastal Regions: Importance Of Quality Flag And Sea Surface Wind Speed, Jacob Anderson Jul 2012

Accuracy Assessment Of Aqua-Modis Aerosol Optical Depth Over Coastal Regions: Importance Of Quality Flag And Sea Surface Wind Speed, Jacob Anderson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Using data collected from 62 coastal stations worldwide from the Aerosol Robotic Network (AERONET) from 2002-2011, accuracy assessments are made for coastal aerosol optical depth (AOD) retrieved from MODIS aboard the Aqua satellite. It is found that coastal AODs (at 550 nm) characterized respectively by the MODIS Dark Land (Land) surface algorithm, the Open Ocean (Ocean) algorithm, and AERONET all exhibit a log-normal distribution. After filtering by quality flags, the coastal MODIS AODs retrieved from the Land and Ocean algorithms are highly correlated with AERONET (with R2≈0.8), but only the Land algorithm AODs fall within the expected error …


Droughtscape, Summer 2012, National Drought Mitigation Center Jul 2012

Droughtscape, Summer 2012, National Drought Mitigation Center

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

Contents

Director’s report 1

Drought expanse 1

Upcoming ranch workshops. 3

Drought outlook and review 4

Spring impacts summary 6

Hawaii impact workshops 9

Remote sensing of drought. 10

China workshop . 12


Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin May 2012

Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin

All Faculty Scholarship for the College of the Sciences

Continuous measurements of both δD and δ18O were performed along a 108.8 m ice core recovered from the East Rongbuk Glacier on the northeast saddle of Mt. Qomolangma (Everest) (28.03° N, 86.96° E, 6518 m above sea level) in September 2002. They provide the first high-resolution historical record of deuterium excess (d) in the central Himalayas. In this paper, we focus on d variability from 1951 to 2001 and its relationship with large scale atmospheric circulation. The d record exhibits significant seasonal variations, with low values in summer and high values in winter, reflecting the atmospheric circulation shift between winter …


An Assessment Of The Relationship Between Air Mass Frequency And Extreme Drought In The Midwest United States, Curtis Walker, Erin Potter, Nicholas Esposito, Melissa Godek Apr 2012

An Assessment Of The Relationship Between Air Mass Frequency And Extreme Drought In The Midwest United States, Curtis Walker, Erin Potter, Nicholas Esposito, Melissa Godek

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Midwest of the United States is a region extensively utilized for agriculture and livestock production despite great susceptibility to widespread and persistent drought. While the location and duration of droughts are related to dynamic meteorological factors, pinpointing when and where a drought will commence, how long it will persist, and when the drought will end, remains a challenge. This investigation examines significant Midwest drought events from a synoptic meteorological perspective through an assessment of air mass frequency over the past decade. A synoptic approach is useful since air masses characteristically describe multiple weather and climate parameters at the same …


Periodicities Of Peak Current And Flash Multiplicity In Cloud To Ground Lightning, Alexander R. Gibbs Apr 2012

Periodicities Of Peak Current And Flash Multiplicity In Cloud To Ground Lightning, Alexander R. Gibbs

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Research on lightning has been conducted on various topics including thunderstorm electrification and climatology of lightning strikes however; there are still some characteristics of lightning that are not well known, such as flash multiplicity and peak current as a function of individual thunderstorms. These characteristics are the leading cause of injuries and damage each year. This study examines a severe weather event in Minnesota on 16 September 2006, in order to determine what may cause peak current and flash multiplicity. Cycles in peak current and flash multiplicity are identified and then associated with CAPE to determine if a thunderstorm’s updraft …


Droughtscape, Spring 2012, National Drought Mitigation Center Apr 2012

Droughtscape, Spring 2012, National Drought Mitigation Center

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

Contents

Director’s report.

Climate Masters 1

Ranch plan workshop . 3

Winter climate summary 4

Winter impacts summary . 6

Zhao research.

Getachew research 0

Other international news

Wardlow move 13

IPCC disaster report .


Water And Energy Balance Response Of A Riparian Wetland To The Removal Of Phragmites Australis, Phillip Mykleby Apr 2012

Water And Energy Balance Response Of A Riparian Wetland To The Removal Of Phragmites Australis, Phillip Mykleby

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Vegetation and climate both play integral roles in water availability, particularly for arid to semi-arid regions. Changes in these variables can lead to extreme shortages in water for regions that rely on water for crop irrigation (i.e., the Great Plains). The objective of this study is to evaluate the impacts of vegetation on water availability in the Republican River basin in central Nebraska. Decreases in streamflow have been observed in the river basin for many years and, as a result, an invasive riparian plant species (Phragmites australis) is being removed in an effort to reduce evapotranspiration and reclaim …


Interannual And Spatial Impacts Of Phenological Transitions, Growing Season Length, And Spring And Autumn Temperatures On Carbon Sequestration: A North America Flux Data Synthesis, Chaoyang Wu, Alemu Gonsamo, Jing Ming Chen, Werner A. Kurz, David T. Price, Peter M. Lafleur, Rachhpal S. Jassal, Danilo Dragoni, Gil Bohrer, Christopher M. Gough, Shashi B. Verma, Andrew E. Suyker, J. William Munger Jan 2012

Interannual And Spatial Impacts Of Phenological Transitions, Growing Season Length, And Spring And Autumn Temperatures On Carbon Sequestration: A North America Flux Data Synthesis, Chaoyang Wu, Alemu Gonsamo, Jing Ming Chen, Werner A. Kurz, David T. Price, Peter M. Lafleur, Rachhpal S. Jassal, Danilo Dragoni, Gil Bohrer, Christopher M. Gough, Shashi B. Verma, Andrew E. Suyker, J. William Munger

School of Natural Resources: Faculty Publications

Understanding feedbacks of ecosystem carbon sequestration to climate change is an urgent step in developing future ecosystem models. Using 187 site-years of flux data observed at 24 sites covering three plant functional types (i.e. evergreen forests (EF), deciduous forests (DF) and non-forest ecosystems (NF) (e.g., crop, grassland, wetland)) in North America, we present an analysis of both interannual and spatial relationships between annual net ecosystem production (NEP) and phenological indicators, including the flux-based carbon uptake period (CUP) and its transitions, degree-day-derived growing season length (GSL), and spring and autumn temperatures. Diverse responses were acquired between annul NEP and these indicators …


A Synoptic Perspective Of The Record 1-2 May 2010 Mid-South Heavy Precipitation Event, Joshua D. Durkee, Lee Campbell, Kyle Berry, Dustin Jordan, Gregory Goodrich, Rezaul Mahmood, Stuart Foster Jan 2012

A Synoptic Perspective Of The Record 1-2 May 2010 Mid-South Heavy Precipitation Event, Joshua D. Durkee, Lee Campbell, Kyle Berry, Dustin Jordan, Gregory Goodrich, Rezaul Mahmood, Stuart Foster

High Plains Regional Climate Center: Staff Publications

During 1–2 May 2010, a series of strong thunderstorms led to 41, 57, and 43 tornado, severe wind, and severe hail reports, respectively, across portions of the southern United States. In addition to severe weather, these storms also distributed recordsetting rainfall amounts across the mid-South region, which contributed to historic flooding across portions of central and western Kentucky and Tennessee (Fig. 1). This heavy precipitation event was sampled by multiple surface observational networks, including (but not limited to) 48 research-grade automated stations from the Kentucky Mesonet (www.kymesonet .org), first-order automated stations from the National Weather Service (NWS; www.ncdc.noaa.gov /oa/ncdc.html), and …


Droughtscape, Winter 2012, National Drought Mitigation Center Jan 2012

Droughtscape, Winter 2012, National Drought Mitigation Center

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

Drought Planning for Kansas Ranchers Jan. 21

South Hoping La Niña Dryness Stays Away

2011 Brought Record-Breaking Extent of D4

Reported Impacts Ease as Growing Season Ends

Disaster Planning in Nanjing at Hohai U

Ag, Fire and Water Supply Topped 2011 Impacts


Assessing Delta Oxygen-18 In The Coral Genus Isopora For Reconstructing Indo-Pacific Regional And Seasonal Climate, Gavin Lemley Jan 2012

Assessing Delta Oxygen-18 In The Coral Genus Isopora For Reconstructing Indo-Pacific Regional And Seasonal Climate, Gavin Lemley

Legacy Theses & Dissertations (2009 - 2024)

Paleoclimate reconstructions often utilize coral reefs with very long time spans such as the genus Porites and Diploastrea, because of their potential to provide centuries of continuous climate records via geochemical signatures. Smaller corals, such as the genus Isopora, have been essentially unexplored as climate archives because their small skeletons (<1 m) and short lifespans (years to decades) do not provide such continuous geochemical records. There has not been a practical application for such corals until recently. In early 2010, the Integrated Ocean Drilling Program Leg 325 (IODP-325) cored drowned fossil reefs off the Great Barrier Reef (GBR) with the objectives of reconstructing sea level and surface ocean conditions since the Last Glacial Maximum. Out of 213 massive fossil corals that were recovered, most were massive Isoporan colonies. A 30-specimen subset of these fossils range in age from ~32,000 to ~11,500 years before present with even temporal spacing, based on preliminary U/Th dating of core catcher samples. This age distribution is excellent for meeting IODP-325 objectives, but the suitability of Isopora for paleoclimate analyses remains unknown.


Net Ecosystem Production (Nep) Of The Great Plains, United States, Daniel Howard, Tagir Gilmanov, Yingxin Gu, Bruce Wylie, Li Zhang Jan 2012

Net Ecosystem Production (Nep) Of The Great Plains, United States, Daniel Howard, Tagir Gilmanov, Yingxin Gu, Bruce Wylie, Li Zhang

Natural Resource Management Faculty Publications

Gross primary production (GPP) and ecosystem respiration (Re) are the fundamental environmental characteristics that promote carbon exchanges with the atmosphere (Chapin and others, 2009), although other exchanges of carbon, such as direct oxidation (Lovett and others, 2006), can modify net ecosystem production (NEP). The accumulation of carbon in terrestrial ecosystems results in systems in which soil organic matter (SOM) carbon often exceeds biomass carbon (Post and Kwon, 2000). This SOM pool exists at a steady state between GPP and Re in ecosystems unless drivers change or the ecosystem endures environmental perturbations (for example, climatic). As indicated by Wilhelm and others …


Impact Of Vegetation On Land-Atmosphere Coupling Strength And Its Implication For Desertification Mitigation Over East Asia, Boksoon Myoung, Yong-Sang Choi, Suk-Jin Choi, Seon Ki Park Jan 2012

Impact Of Vegetation On Land-Atmosphere Coupling Strength And Its Implication For Desertification Mitigation Over East Asia, Boksoon Myoung, Yong-Sang Choi, Suk-Jin Choi, Seon Ki Park

Mathematics, Physics, and Computer Science Faculty Articles and Research

Desertification of the East Asian drylands and the consequent dust transport have been serious concerns for adjacent Asian countries as well as the western United States. Tree planting has been considered one applicable strategy to mitigate the desertification. However, the desired effect of the tree planting would not be brought to fruition unless the newly planted trees change the coupling characteristics between the land and the atmosphere. Based on this perception, we attempt to clarify the effects of vegetation on the coupling strength between the atmosphere and land surface, and we suggest the most efficient areas of tree planting for …