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Department of Earth and Atmospheric Sciences: Faculty Publications

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Articles 121 - 150 of 670

Full-Text Articles in Earth Sciences

Early Miocene Quantitative Calcareous Nannofossil Biostratigraphy From The Tropical Atlantic, Waheed A. Albasrawi, David K. Watkins Jan 2017

Early Miocene Quantitative Calcareous Nannofossil Biostratigraphy From The Tropical Atlantic, Waheed A. Albasrawi, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

A quantitative analysis of calcareous nannofossils was conducted on lower Miocene sediments from Ocean Drilling Program Hole 959A on the West African margin. Combined with data from previous investigations of the lower Miocene from the tropical Atlantic, this research identifies and tests the viability of markers used in current zonation schemes, identifies alternative markers for age boundaries, and examines statistically the most probable order of events in the lower Miocene with the use of the ranking and scaling method (RASC).

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Interactions Of A Paleocene River, A Rising Fold, And Early-Diagenetic Concretions, David B. Loope, Ross Secord Jan 2017

Interactions Of A Paleocene River, A Rising Fold, And Early-Diagenetic Concretions, David B. Loope, Ross Secord

Department of Earth and Atmospheric Sciences: Faculty Publications

The relative rates of sediment accumulation, erosion, and structural uplift determine whether a growing fold develops positive topographic relief, is beveled by antecedent streams, or is buried under thick growth strata. When folds rise in subsiding basins, upward, convergent flow of groundwater through the permeable growth strata that underlie antecedent streams enhances the flux of ions required for concretion growth. Early diagenetic concretions that grow in such alluvial strata may constitute the only clasts larger than sand size available for transport when antecedent streams become erosive. The first reworked concretions deposited by these streams should accurately mark the transition from …

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Polarimetric Radar Metrics Related To Tornado Life Cycles And Intensity In Supercell Storms, Matthew S. Van Den Broeke Jan 2017

Polarimetric Radar Metrics Related To Tornado Life Cycles And Intensity In Supercell Storms, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Polarimetric radar signatures have been related to the typical evolution of supercell storms, including through tornado life cycles. Now that polarimetric radar observations are available for a large sample of supercell storms, time series of new radar metrics can be derived. These metrics can be compared with phases of known tornado life cycles in an effort to develop new methods of anticipating tornadoes and to increase understanding of storm-scale structural and microphysical changes through supercell and tornado life cycles. In this paper, radar metrics including measures of differential reflectivity ZDR columns, ZDR arcs, polarimetrically inferred hailfall regions, and …

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The Possible Role Of Density Current Dynamics In The Generation Of Low-Level Vertical Vorticity In Supercells, Adam L. Houston Jan 2017

The Possible Role Of Density Current Dynamics In The Generation Of Low-Level Vertical Vorticity In Supercells, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

A physical mechanism based on density current dynamics is proposed to explain the generation of low-level vertical vorticity in supercells. This mechanism may serve as one explanation for the associative relationship between environmental low-level vertical shear and the occurrence of significant tornadoes. The mechanism proposed herein represents an indirect connection to the generation of strong surface-based rotation: the barotropic horizontal vorticity associated with the vertical shear acts to amplify existing rotation but does not directly contribute to surface rotation. The proposed mechanism couples the likelihood of a tornado to the vertical shear through the pattern of vertical motion induced through …

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Tornado Warning Response And Perceptions Among Undergraduates In Nebraska, Sabrina T. Jauernic, Matthew S. Van Den Broeke Jan 2017

Tornado Warning Response And Perceptions Among Undergraduates In Nebraska, Sabrina T. Jauernic, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Few studies show how university students perceive and respond to tornado warnings. Lacking in the literature are investigations of what influences perceptions of tornado risk among this population and how these perceptions may influence actions. Through an online survey of 640 undergraduates enrolled at a large university in Nebraska, significant relationships were found between student demographics, perceptions, and response actions. Tornado mythology relevant to the local city influenced perceptions so that students felt the city was less at risk than surrounding rural land. Confirming risk before sheltering remained popular, with some students choosing to never seek shelter during a warning. …

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Tropospheric Emissions: Monitoring Of Pollution (Tempo), P. Zoogman, X. Liu, R. M. Suleiman, W. F. Pennington, D. E. Flittner, J. A. Al-Saadi, B. B. Hinton, D. K. Nicks, M. J. Newchurch, J. L. Carr, S. J. Janz, M. R. Andraschko, A. Arola, B. D. Baker, B. P. Canova, C. Chan Miller, R. C. Cohen, J. E. Davis, M. E. Dussault, D. P. Edwards, J. Fishman, A. Ghulam, G. Gonzalez Abad, M. Grutter, J. R. Herman, J. Houck, D. J. Jacob, J. Joiner, B. J. Kerridge, J. Kim, N. A. Krotkov, L. Lamsal, C. Li, A. Lindfors, R. V. Martin, C. T. Mcelroy, C. Mclinden, V. Natraj, D. O. Neil, C. R. Nowlan, E. J. O'Sullivan, P. I. Palmer, R. B. Pierce, M. R. Pippin, A. Saiz-Lopez, R. J. D. Spurr, J. J. Szykman, O. Torres, J. P. Veefkind, B. Veihelmann, H. Wang, J. Wang Jan 2017

Tropospheric Emissions: Monitoring Of Pollution (Tempo), P. Zoogman, X. Liu, R. M. Suleiman, W. F. Pennington, D. E. Flittner, J. A. Al-Saadi, B. B. Hinton, D. K. Nicks, M. J. Newchurch, J. L. Carr, S. J. Janz, M. R. Andraschko, A. Arola, B. D. Baker, B. P. Canova, C. Chan Miller, R. C. Cohen, J. E. Davis, M. E. Dussault, D. P. Edwards, J. Fishman, A. Ghulam, G. Gonzalez Abad, M. Grutter, J. R. Herman, J. Houck, D. J. Jacob, J. Joiner, B. J. Kerridge, J. Kim, N. A. Krotkov, L. Lamsal, C. Li, A. Lindfors, R. V. Martin, C. T. Mcelroy, C. Mclinden, V. Natraj, D. O. Neil, C. R. Nowlan, E. J. O'Sullivan, P. I. Palmer, R. B. Pierce, M. R. Pippin, A. Saiz-Lopez, R. J. D. Spurr, J. J. Szykman, O. Torres, J. P. Veefkind, B. Veihelmann, H. Wang, J. Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

TEMPO was selected in 2012 by NASA as the first Earth Venture Instrument, for launch between 2018 and 2021. It will measure atmospheric pollution for greater North America from space using ultraviolet and visible spectroscopy. TEMPO observes from Mexico City, Cuba, and the Bahamas to the Canadian oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution (~2.1kmN/S x 4.4 kmE/W at 36.5°N, 100°W). TEMPO provides a tropospheric measurement suite that includes the key elements of tropospheric air pollution chemistry, as well as contributing to carbon cycle knowledge. Measurements are made hourly from geostationary (GEO) …

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Intercomparison Of Modis And Viirs Fire Products In Khanty-Mansiysk Russia: Implications For Characterizing Gas Flaring From Space, Ambrish Sharma, Jun Wang, Elizabeth M. Lennartson Jan 2017

Intercomparison Of Modis And Viirs Fire Products In Khanty-Mansiysk Russia: Implications For Characterizing Gas Flaring From Space, Ambrish Sharma, Jun Wang, Elizabeth M. Lennartson

Department of Earth and Atmospheric Sciences: Faculty Publications

Gas flaring is commonly used by industrial plants for processing oil and natural gases in the atmosphere, and hence is an important anthropogenic source for various pollutants including CO2, CO, and aerosols. This study evaluates the feasibility of using satellite data to characterize gas flaring from space by focusing on the Khanty-Mansiysk Autonomous Okrug in Russia, a region that is well known for its dominant gas flaring activities. Multiple satellite-based thermal anomaly data products at night are intercompared and analyzed, including MODIS (Moderate Resolution Imaging Spectroradiometer) Terra level 2 Thermal Anomalies product (MOD14), MODIS Aqua level 2 Thermal …

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Evaporation From A Shallow, Saline Lake In The Nebraska Sandhills: Energy Balance Drivers Of Seasonal And Interannual Variability, Diego Andrés Riveros-Iregui, John Lenters, Colin Peake, John T. Ong, Nathan C. Healey, Vitaly A. Zlotnik Jan 2017

Evaporation From A Shallow, Saline Lake In The Nebraska Sandhills: Energy Balance Drivers Of Seasonal And Interannual Variability, Diego Andrés Riveros-Iregui, John Lenters, Colin Peake, John T. Ong, Nathan C. Healey, Vitaly A. Zlotnik

Department of Earth and Atmospheric Sciences: Faculty Publications

Despite potential evaporation rates in excess of the local precipitation, dry climates often support saline lakes through groundwater inputs of water and associated solutes. These groundwater-fed lakes are important indicators of environmental change, in part because their shallow water levels and salinity are very sensitive to weather and climatic variability. Some of this sensitivity arises from high rates of open-water evaporation, which is a dominant but poorly quantified process for saline lakes. This study used the Bowen ratio energy budget method to calculate open-water evaporation rates for Alkali Lake, a saline lake in the Nebraska Sandhills region (central United States), …

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Evaluation Of Aerosol Optical Depth And Aerosol Models From Viirs Retrieval Algorithms Over North China Plain, Jun Zhu, Xiangao Xia, Jun Wang, Huizheng Che, Hongbin Chen, Jinqiang Zhang, Xiaoguang Xu, Robert Levy, Min Oo, Robert Holz, Mohammed Ayoub Jan 2017

Evaluation Of Aerosol Optical Depth And Aerosol Models From Viirs Retrieval Algorithms Over North China Plain, Jun Zhu, Xiangao Xia, Jun Wang, Huizheng Che, Hongbin Chen, Jinqiang Zhang, Xiaoguang Xu, Robert Levy, Min Oo, Robert Holz, Mohammed Ayoub

Department of Earth and Atmospheric Sciences: Faculty Publications

The first Visible Infrared Imaging Radiometer Suite (VIIRS) was launched on Suomi National Polar-orbiting Partnership (S-NPP) satellite in late 2011. Similar to the Moderate resolution Imaging Spectroradiometer (MODIS), VIIRS observes top-of-atmosphere spectral reflectance and is potentially suitable for retrieval of the aerosol optical depth (AOD). The VIIRS Environmental Data Record data (VIIRS_EDR) is produced operationally by NOAA, and is based on the MODIS atmospheric correction algorithm. The “MODIS-like” VIIRS data (VIIRS_ML) are being produced experimentally at NASA, from a version of the “dark-target” algorithm that is applied to MODIS. In this study, the AOD and aerosol model types from these …

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Evolution Of A Long-Track Violent Tornado Within A Simulated Supercell, Leigh Orf, Robert Wilhelmson, Bruce Lee, Catherine Finley, Adam L. Houston Jan 2017

Evolution Of A Long-Track Violent Tornado Within A Simulated Supercell, Leigh Orf, Robert Wilhelmson, Bruce Lee, Catherine Finley, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

Utilizing state-of-the-art visualization and analysis software, we explore the evolution of a violent tornado within a simulated supercell thunderstorm and describe associated computational challenges.

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The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu Jun 2016

The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu

Department of Earth and Atmospheric Sciences: Faculty Publications

The reactivation potential of pre-existing deep-seated structures influences deformation structures produced in subsequent compression. This contribution investigates thrust geometries produced in surface thrust sheets of the Sawtooth Range, Montana, USA, deforming over a previously faulted sedimentary section. Surface thrust fault patterns were picked using existing maps and remote sensing. Thrust location and regional transport direction was also verified in the field. These observations were used to design a series of analogue models, involving deformation of a brittle cover sequence over a lower section with varying numbers of vertical faults. A final model tested the effect of decoupling the upper cover …

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Potential Application Of Viirs Day/Night Band For Monitoring Nighttime Surface Pm2.5 Air Quality From Space, Jun Wang, Clint Aegerter, Xiaoguang Xu, James J. Szykman Jan 2016

Potential Application Of Viirs Day/Night Band For Monitoring Nighttime Surface Pm2.5 Air Quality From Space, Jun Wang, Clint Aegerter, Xiaoguang Xu, James J. Szykman

Department of Earth and Atmospheric Sciences: Faculty Publications

A pilot study is conducted to illustrate the potential of using radiance data collected by the Day/Night Band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polarorbiting Partnership (S-NPP) satellite for particulate matter (PM) air quality monitoring at night. The study focuses on the moonless and cloudless nights in Atlanta, Georgia during August-October 2012.We show with radiative transfer calculations that DNB at night is sensitive to the change of aerosols and much less sensitive to the change of water vapor in the atmosphere illuminated by common outdoor light bulbs at the surface. We further show …

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Sandstones And Utah’S Canyon Country: Deposition, Diagenesis, Exhumation, And Landscape Evolution, David Loope, Richard Kettler, Kendra Murray, Joel Pederson, Peter Reiners Jan 2016

Sandstones And Utah’S Canyon Country: Deposition, Diagenesis, Exhumation, And Landscape Evolution, David Loope, Richard Kettler, Kendra Murray, Joel Pederson, Peter Reiners

Department of Earth and Atmospheric Sciences: Faculty Publications

South-central Utah’s prominent sandstones and deeply dissected landscapes are the focus of this four-day trip, which begins and ends in Grand Junction, Colorado. Studies of the apatite grains in sandstones adjacent to igneous intrusions are revealing new information on the timing and rate of Cenozoic erosion. Iron-oxide-cemented concretions in other rocks record how reduced-iron carbonates and subsurface microbes interacted when near-surface, oxygenated waters started to flush the reducing, CO2-rich waters from Colorado Plateau aquifers. New geochronologic techniques that are being applied to the plateau rocks have the potential to expand our knowledge of how diagenetic episodes relate to …

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Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Experiments. Part Ii: North American Precipitation, Q. Steven Hu, Michael C. Veres Jan 2016

Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Experiments. Part Ii: North American Precipitation, Q. Steven Hu, Michael C. Veres

Department of Earth and Atmospheric Sciences: Faculty Publications

This is the second part of a two-part paper that addresses deterministic roles of the sea surface temperature (SST) anomalies associated with the Atlantic multidecadal oscillation (AMO) in variations of atmospheric circulation and precipitation in the Northern Hemisphere, using a sequence of idealized model runs at the spring equinox conditions. This part focuses on the effect of the SST anomalies on North American pre- cipitation. Major results show that, in the model setting closest to the real-world situation, a warm SST anomaly in the North Atlantic Ocean causes suppressed precipitation in central, western, and northern North America but more precipitation …

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Intercomparison Of Unmanned Aircraftborne And Mobile Mesonet Atmospheric Sensors, Adam L. Houston, Roger J. Laurence Iii, Tevis W. Nichols, Sean Waugh, Brian Argrow, Conrad L. Ziegler Jan 2016

Intercomparison Of Unmanned Aircraftborne And Mobile Mesonet Atmospheric Sensors, Adam L. Houston, Roger J. Laurence Iii, Tevis W. Nichols, Sean Waugh, Brian Argrow, Conrad L. Ziegler

Department of Earth and Atmospheric Sciences: Faculty Publications

Results are presented from an intercomparison of temperature, humidity, and wind velocity sensors of the Tempest unmanned aircraft system (UAS) and the National Severe Storms Laboratory (NSSL) mobile mesonet (NSSL-MM). Contemporaneous evaluation of sensor performance was facilitated by mounting the Tempest wing with attached sensors to the NSSL-MM instrument rack such that the Tempest and NSSL-MM sensors could collect observations within a nearly identical airstream. This intercomparison was complemented by wind tunnel simulations designed to evaluate the impact of the mobile mesonet vehicle on the observed wind velocity. The intercomparison revealed strong correspondence between the temperature and relative humidity (RH) …

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Satellite-Based Global Volcanic So2 Emissions And Sulfate Direct Radiative Forcing During 2005–2012, Cui Ge, Jun Wang, Simon Carn, Kai Yang, Paul Ginox, Nickolay Krotkov Jan 2016

Satellite-Based Global Volcanic So2 Emissions And Sulfate Direct Radiative Forcing During 2005–2012, Cui Ge, Jun Wang, Simon Carn, Kai Yang, Paul Ginox, Nickolay Krotkov

Department of Earth and Atmospheric Sciences: Faculty Publications

An 8 year volcanic SO2 emission inventory for 2005–2012 is obtained based on satellite measurements of SO2 from OMI (Ozone Monitoring Instrument) and ancillary information from the Global Volcanism Program. It includes contributions from global volcanic eruptions and from eight persistently degassing volcanoes in the tropics. It shows significant differences in the estimate of SO2 amount and injection height for medium to large volcanic eruptions as compared to the counterparts in the existing volcanic SO2 database. Emissions from Nyamuragira (DR Congo) in November 2006 and Grímsvötn (Iceland) in May 2011 that were not included in the …

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A Multi-Sensor View Of The 2012 Central Plains Drought From Space, Jun Wang, Amy L. Kessner, Clint Aegerter, Ambrish Sharma, Laura Judd, Brian D. Wardlow, Jinsheng You, Martha Shulski, Suat Irmak, Ayse Kilic, Jing Zeng Jan 2016

A Multi-Sensor View Of The 2012 Central Plains Drought From Space, Jun Wang, Amy L. Kessner, Clint Aegerter, Ambrish Sharma, Laura Judd, Brian D. Wardlow, Jinsheng You, Martha Shulski, Suat Irmak, Ayse Kilic, Jing Zeng

Department of Earth and Atmospheric Sciences: Faculty Publications

In summer of 2012, the Central Plains of the United States experienced its most severe drought since the ground-based data record began in the late 1900s. By using comprehensive satellite data from MODIS (Moderate Resolution Imaging Spectroradiometer) and TRMM (Tropical Rainfall Measuring Mission), along with in-situ observations, this study documents the geophysical parameters associated with this drought, and thereby providing, for the first time, a large-scale observation-based view of the extent to which the land surface temperature and vegetation can likely be affected by both the severe drought and the agricultural response (irrigation) to the drought. Over non-irrigated area, 2012 …

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Accommodation Of Penetrative Strain During Deformation Above A Ductile Décollement, Bailey A. Lathrop, Caroline M. Burberry Jan 2016

Accommodation Of Penetrative Strain During Deformation Above A Ductile Décollement, Bailey A. Lathrop, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

The accommodation of shortening by penetrative strain is widely considered as an important process during contraction, but the distribution and magnitude of penetrative strain in a contractional system with a ductile décollement are not well understood. Penetrative strain constitutes the proportion of the total shortening across an orogen that is not accommodated by the development of macroscale structures, such as folds and thrusts. In order to create a framework for understanding penetrative strain in a brittle system above a ductile décollement, eight analog models, each with the same initial configuration, were shortened to different amounts in a deformation apparatus. Models …

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The Geologic Context Of Wonderstone: A Complex, Outcrop-Scaled Pattern Of Ironoxide Cement, Derek T. Burgess, Richard M. Kettler, David B. Loope Jan 2016

The Geologic Context Of Wonderstone: A Complex, Outcrop-Scaled Pattern Of Ironoxide Cement, Derek T. Burgess, Richard M. Kettler, David B. Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

Although siderite is a widespread early diagenetic mineral in fluvial systems, it is unstable in oxidizing environments and destroyed in permeable rocks that experience uplift and exhumation. The products of siderite oxidation, however, (mm- to cm-scale rhombs, concretions, and complex bands of iron-oxide cement) are widespread in the rock record of fluvial systems. The fluvial channels of the Shinarump Member of the Chinle Formation in southern Utah and northern Arizona, U.S.A., provide an excellent suite of examples of diagenetic features produced by Triassic and Neogene oxidation of early diagenetic siderite. These diagenetic features also provide direct evidence of the level …

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Polarimetric Remote Sensing In Oxygen A And B Bands: Sensitivity Study And Information Content Analysis For Vertical Profile Of Aerosols, Shouguo Ding, Jun Wang, Xiaoguang Xu Jan 2016

Polarimetric Remote Sensing In Oxygen A And B Bands: Sensitivity Study And Information Content Analysis For Vertical Profile Of Aerosols, Shouguo Ding, Jun Wang, Xiaoguang Xu

Department of Earth and Atmospheric Sciences: Faculty Publications

Theoretical analysis is conducted to reveal the information content of aerosol vertical profile in space-borne measurements of the backscattered radiance and degree of linear polarization (DOLP) in oxygen (O2) A and B bands. Assuming a quasi-Gaussian shape for aerosol vertical profile characterized by peak height H and half width y (at half maximum), the Unified Linearized Vector Radiative Transfer Model (UNL-VRTM) is used to simulate the Stokes fourvector elements of upwelling radiation at the top of atmosphere (TOA) and their Jacobians with respect to H and y. Calculations for different aerosol types and different combinations of H …

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Polarimetric Radar Observations Of Precipitation Type And Rate From The 2–3 March 2014 Winter Storm In Oklahoma And Arkansas, Matthew S. Van Den Broeke, Dana M. Tobin, Matthew R. Kumjian Jan 2016

Polarimetric Radar Observations Of Precipitation Type And Rate From The 2–3 March 2014 Winter Storm In Oklahoma And Arkansas, Matthew S. Van Den Broeke, Dana M. Tobin, Matthew R. Kumjian

Department of Earth and Atmospheric Sciences: Faculty Publications

A powerful winter storm affected the south-central United States in early March 2014, accompanied by elevated convective cells with hail and high rates of sleet, freezing rain, and snow. During portions of the event the thermal profile exhibited a shallow surface cold layer and warm, unstable air aloft. Precipitation falling into the cold layer refroze into ice pellets and was accompanied by a polarimetric refreezing signature and numerous crowdsourced surface ice pellet reports. Quasi-vertical profiles of the polarimetric variables indicated an enhanced reflectivity factor ZHH below the melting layer bright band and enhanced low-level differential reflectivity ZDR values …

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Polarimetric Variability Of Classic Supercell Storms As A Function Of Environment, Matthew S. Van Den Broeke Jan 2016

Polarimetric Variability Of Classic Supercell Storms As A Function Of Environment, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Classic supercell storms occur in a generally well understood environment characterized by instability and vertical wind shear. Within this broadly favorable environment, large day-to-day variability in environmental parameters may lead to widely varying radar presentation of storms. Of interest here is whether specific storm structures exhibit repeatable characteristics in similar environments and whether radar presentation can be predicted with knowledge of environmental characteristics. Specifically, this paper focuses on (i) updraft characteristics inferred using differential reflectivity ZDR columns, (ii) characteristics of storm-relative inflow inferred using ZDR arcs, and (iii) areal extent and cyclicality of polarimetrically inferred hailfall at low levels. Variability …

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Climatology, Synoptic Conditions, And Misanalyses Of Mississippi River Valley Drylines, Rebecca S. Duell, Matthew S. Van Den Broeke Jan 2016

Climatology, Synoptic Conditions, And Misanalyses Of Mississippi River Valley Drylines, Rebecca S. Duell, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

The dryline is an important focal point for convection initiation. Although drylines most commonly occur on the southern Great Plains, dryline passages and subsequent severe weather outbreaks have been documented in the Mississippi River valley. This study presents a 15-yr (1999–2013) climatology of these Mississippi River valley drylines and associated severe weather. Additionally, synoptic patterns are identified that may result in drylines moving atypically far eastward into the Mississippi River valley. In total, 39 Mississippi River valley drylines (hereafter referred to as MRV drylines) were identified from the North American Regional Reanalysis (NARR) dataset through the study period. Mean and …

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Applying Advanced Ground-Based Remote Sensing In The Southeast Asian Maritime Continent To Characterize Regional Proficiencies In Smoke Transport Modeling, James R. Campbell, Cui Ge, Jun Wang, Ellsworth J. Welton, Anthony Bucholtz, Edward J. Hyer, Elizabeth A. Reid, Boon Ning Chew, Soo-Chin Liew, Santo V. Salinas, Simon Lolli, Kathleen C. Kaku, Peng Lynch, Mastura Mahmud, Maznorizan Mohamad, Brent N. Holben Jan 2016

Applying Advanced Ground-Based Remote Sensing In The Southeast Asian Maritime Continent To Characterize Regional Proficiencies In Smoke Transport Modeling, James R. Campbell, Cui Ge, Jun Wang, Ellsworth J. Welton, Anthony Bucholtz, Edward J. Hyer, Elizabeth A. Reid, Boon Ning Chew, Soo-Chin Liew, Santo V. Salinas, Simon Lolli, Kathleen C. Kaku, Peng Lynch, Mastura Mahmud, Maznorizan Mohamad, Brent N. Holben

Department of Earth and Atmospheric Sciences: Faculty Publications

This work describes some of the most extensive ground-based observations of the aerosol profile collected in Southeast Asia to date, highlighting the challenges in simulating these observations with amesoscale perspective. An 84-hWRFModel coupled with chemistry (WRF-Chem)mesoscale simulation of smoke particle transport at Kuching, Malaysia, in the southern Maritime Continent of Southeast Asia is evaluated relative to a unique collection of continuous ground-based lidar, sun photometer, and 4-h radiosonde profiling. The period was marked by relatively dry conditions, allowing smoke layers transported to the site unperturbed by wet deposition to be common regionally. The model depiction is reasonable overall. Core thermodynamics, …

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Did The Widespread Haze Pollution Over China Increase During The Last Decade? A Satellite View From Space, Minghui Tao, Liangfu Chen, Zifeng Wang, Jun Wang, Jinhua Tao, Xinhui Wang Jan 2016

Did The Widespread Haze Pollution Over China Increase During The Last Decade? A Satellite View From Space, Minghui Tao, Liangfu Chen, Zifeng Wang, Jun Wang, Jinhua Tao, Xinhui Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

Widespread haze layers usually cover China like low clouds, exerting marked influence on air quality and regional climate. With recent Collection 6 MODISDeep Blue aerosol data in 2000–2015, we analyzed the trends of regional haze pollution and the corresponding influence of atmospheric circulation in China. Satellite observations show that regional haze pollution is mainly concentrated in northern and central China. The annual frequency of regional haze in northern China nearly doubles between 2000 and 2006, increasing from30–50 to 80–90 days. Though there is amarked decrease in annual frequency during 2007–2009 due to both reduction of anthropogenic emissions and changes of …

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Satellite-Based Global Volcanic So2 Emissions And Sulfate Direct Radiative Forcing During 2005–2012, Cui Ge, Jun Wang, Simon Carn, Kai Yang, Paul Ginoux, Nickolay Krotkov Jan 2016

Satellite-Based Global Volcanic So2 Emissions And Sulfate Direct Radiative Forcing During 2005–2012, Cui Ge, Jun Wang, Simon Carn, Kai Yang, Paul Ginoux, Nickolay Krotkov

Department of Earth and Atmospheric Sciences: Faculty Publications

An 8 year volcanic SO2 emission inventory for 2005–2012 is obtained based on satellite measurements of SO2 from OMI (Ozone Monitoring Instrument) and ancillary information from the Global Volcanism Program. It includes contributions from global volcanic eruptions and from eight persistently degassing volcanoes in the tropics. It shows significant differences in the estimate of SO2 amount and injection height for medium to large volcanic eruptions as compared to the counterparts in the existing volcanic SO2 database. Emissions fromNyamuragira (DR Congo) in November 2006 and Grímsvötn (Iceland) in May 2011 that were not included in the Intergovernmental …

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Biomass Burning, Land-Cover Change, And The Hydrological Cycle In Northern Sub-Saharan Africa, Charles Ichoku, Luke T. Ellison, K. Elena Willmot, Toshihisa Matsui, Amin K. Dezfuli, Charles K. Gatebe, Jun Wang, Eric M. Wilcox, Jejung Lee, Jimmy Adegoke, Churchill Okonkwo, John Bolten, Frederick S. Policelli, Shahid Habib Jan 2016

Biomass Burning, Land-Cover Change, And The Hydrological Cycle In Northern Sub-Saharan Africa, Charles Ichoku, Luke T. Ellison, K. Elena Willmot, Toshihisa Matsui, Amin K. Dezfuli, Charles K. Gatebe, Jun Wang, Eric M. Wilcox, Jejung Lee, Jimmy Adegoke, Churchill Okonkwo, John Bolten, Frederick S. Policelli, Shahid Habib

Department of Earth and Atmospheric Sciences: Faculty Publications

The Northern Sub-Saharan African (NSSA) region, which accounts for 20%–25%of the global carbon emissions from biomass burning, also suffers from frequent drought episodes and other disruptions to the hydrological cycle whose adverse societal impacts have been widely reported during the last several decades. This paper presents a conceptual framework of the NSSA regional climate system components that may be linked to biomass burning, as well as detailed analyses of a variety of satellite data for 2001–2014 in conjunction with relevant model-assimilated variables. Satellite fire detections in NSSA show that the vast majority (>75%) occurs in the savanna and woody …

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8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble Nov 2015

8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

The rocky and indented coast of NW Iberia is characterized by the presence of highly valuable and vulnerable, small and shallow barrier– lagoon systems structurally controlled. The case study was selected to analyse barrier–lagoon evolution based on detailed sedimentary architecture, chronology, geochemical and biological proxies. The main objective is to test the hypothesis of structural control and the significance at regional scale of any highenergy event recorded. This work is also aimed at identifying general patterns and conceptualizing the formation and evolution of this type of coastal systems. The results allowed us to establish a conceptual model of Holocene evolution …

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Integration And Delivery Of Interferometric Synthetic Aperture Radar [Insar] Data Into Stormwater Planning Within Karst Terranes, Brian Bruckno, Andrea Vaccari, Edward Hoppe, Scott Acton, Elizabeth Campbell Oct 2015

Integration And Delivery Of Interferometric Synthetic Aperture Radar [Insar] Data Into Stormwater Planning Within Karst Terranes, Brian Bruckno, Andrea Vaccari, Edward Hoppe, Scott Acton, Elizabeth Campbell

Department of Earth and Atmospheric Sciences: Faculty Publications

As part of two USDOT-funded studies focused on the development of satellite-based Interferometric Synthetic Aperture Radar (InSAR) technology, the researchers integrated InSAR-derived point cloud data into the transportation design process to optimize the location of a stormwater management system in a karst terrane. After initial validation, the InSAR data (over 1.67 million data points comprising various “scatterers”) were brought into a GIS dataframe and georeferenced to locations of known sinkholes. This dataset was then used to evaluate karst hazard within a 40x40km data frame located in the Valley and Ridge Province of Virginia. The group identified systematic kinematic differences in …

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Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide Oct 2015

Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide

Department of Earth and Atmospheric Sciences: Faculty Publications

A new species of Aulacoseira Thwaites is described from piston core samples from Ho Ba Bê in the karst region of northern Viêt Nam. Although it closely resembles Aulacoaseira subborealis (Nygaard) Denys, Muylaert & Krammer, A. stevensiae Weide sp. nov. is designated a new species based mainly on morphological differences in the spines, including invariably inclined spines that are rounded, differences in the Ringleiste, areola pattern and overall size. Aulacoseira stevensiae is present throughout a core that spans the last 500 years. It was a major component of the diatom community, but the populations have recently decreased, possibly being outcompeted …

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