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Droughtscape- Fall 2012, National Drought Mitigation Center 2012 University of Nebraska-Lincoln

Droughtscape- Fall 2012, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

CONTENTS

Director’s report ....................... 1

Updated resources ................... 1

Drought outlook and review... 2

2012 and past droughters..... 4

Summer impacts summary.... 6

Urban planners and drought..... 9

USDM wins CLEAN seal... 10

Meixiu Yu's Chinese SPEI... 11

Ethiopian project..... 12

Mexican VegDRI.... 13

Drought monitor sculpture.... 14


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

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 …


A Statistical Model To Forecast Short-Term Atlantic Hurricane Intensity, Kevin Law, Jay Hobgood 2012 Marshall University

A Statistical Model To Forecast Short-Term Atlantic Hurricane Intensity, Kevin Law, Jay Hobgood

Kevin Law

An alternative 24-h statistical hurricane intensity model is presented and verified for 13 hurricanes during the 2004–05 seasons. The model uses a new method involving a discriminant function analysis (DFA) to select from a collection of multiple regression equations. These equations were developed to predict the future 24-h wind speed increase and the 24-h pressure drop that were constructed from a dataset of 103 hurricanes from 1988 to 2003 that utilized 25 predictors of rapid intensification. The accuracy of the 24-h wind speed increase models was tested and compared with the official National Hurricane Center (NHC) 24-h intensity forecasts, which …


The Impact Of Oceanic Heat Content On The Rapid Intensification Of Atlantic Hurricanes, Kevin Law 2012 Marshall University

The Impact Of Oceanic Heat Content On The Rapid Intensification Of Atlantic Hurricanes, Kevin Law

Kevin Law

With the increased infrastructure and amount of people living along the United States coastline, it is imperative to improve the accuracy of Atlantic hurricane intensity forecasts. Over the last 10 years, there have been many Atlantic hurricanes, including Hurricanes Katrina and Charley that surprised many forecasters with their rapid intensification and power. The rapid intensification of tropical cyclones is the most serious aspect, when it comes to forecasting. It is generally accepted that sufficient surface ocean temperatures (approximately 26°C) are needed to produce and sustain tropical cyclone formation. However, the sea-surface temperature (SST) has shown not to be critical in …


A New Nonlinear Analytical Model For Canopy Flow Over A Forested Hill, Weiguo Wang, Chuixiang Yi 2012 National Oceanic and Atmospheric Administration

A New Nonlinear Analytical Model For Canopy Flow Over A Forested Hill, Weiguo Wang, Chuixiang Yi

Publications and Research

A new nonlinear analytical model for canopy flow over gentle hills is presented. This model is established based on the assumption that three major forces (pressure gradient, Reynolds stress gradient, and nonlinear canopy drag) within canopy are in balance for gentle hills under neutral conditions. The momentum governing equation is closed by the velocity-squared law. This new model has many advantages over the model developed by Finnigan and Belcher (2004, hereafter referred to as FB04) in predicting canopy wind velocity profiles in forested hills in that: (1) this model predictions are more realistic because the surface drag can be taken …


Coastal Hurricane Damage Assessment Via Wavelet Transform Of Remotely Sensed Imagery, Ricky Carl Crowsey 2012 University of Southern Mississippi

Coastal Hurricane Damage Assessment Via Wavelet Transform Of Remotely Sensed Imagery, Ricky Carl Crowsey

Dissertations

This dissertation uses post storm imagery processed using wavelet transforms to investigate the capability of wavelet transform-based methods to classify post storm damage of residential areas. Five level Haar, Meyer, Symlets, and Coiflets wavelet transform decompositions of the post storm imagery are inputs to damage classification models of post hurricane and tornado damage. Hurricanes Ike, Rita, Katrina, and Ivan are examined as are the 2011 Joplin and Tuscaloosa tornadoes.

Wavelet transform-based classification methods yielded varying classification accuracies for the four hurricanes examined, ranging from 67 percent to 89 percent classification accuracy for classification models informed by samples from the storms …


An Analysis Of Fast Photochemistry Over High Northern Latitudes During Spring And Summer Using In-Situ Observations From Arctas And Topse, J R. Olson, J H. Crawford, William H. Brune, J Mao, Xinrong Ren, A Fried, B Anderson, E C. Apel, M Beaver, D R. Blake, G Chen, John D. Crounse, Jack E. Dibb, Glenn Diskin, S R. Hall, L Gregory Huey, D Knapp, D Richter, D Riemer, J St. Clair, Kirk Ullman, J Walega, P Weibring, Andrew Weinheimer, Paul Wennberg, Armin Wisthaler 2012 NASA

An Analysis Of Fast Photochemistry Over High Northern Latitudes During Spring And Summer Using In-Situ Observations From Arctas And Topse, J R. Olson, J H. Crawford, William H. Brune, J Mao, Xinrong Ren, A Fried, B Anderson, E C. Apel, M Beaver, D R. Blake, G Chen, John D. Crounse, Jack E. Dibb, Glenn Diskin, S R. Hall, L Gregory Huey, D Knapp, D Richter, D Riemer, J St. Clair, Kirk Ullman, J Walega, P Weibring, Andrew Weinheimer, Paul Wennberg, Armin Wisthaler

Earth Sciences

Observations of chemical constituents and meteorological quantities obtained during the two Arctic phases of the airborne campaign ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) are analyzed using an observationally constrained steady state box model. Measurements of OH and HO2 from the Penn State ATHOS instrument are compared to model predictions. Forty percent of OH measurements below 2 km are at the limit of detection during the spring phase (ARCTAS-A). While the median observed-to-calculated ratio is near one, both the scatter of observations and the model uncertainty for OH are at the magnitude of …


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

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 …


Modeling Chemistry In And Above Snow At Summit, Greenland – Part 2: Impact Of Snowpack Chemistry On The Oxidation Capacity Of The Boundary Layer, J L. Thomas, Jack E. Dibb, L Gregory Huey, J Liao, D Tanner, Barry Lefer, R von Glasow, J Stutz 2012 Universite de Versailles Saint-Quentin-en-Yvelines

Modeling Chemistry In And Above Snow At Summit, Greenland – Part 2: Impact Of Snowpack Chemistry On The Oxidation Capacity Of The Boundary Layer, J L. Thomas, Jack E. Dibb, L Gregory Huey, J Liao, D Tanner, Barry Lefer, R Von Glasow, J Stutz

Earth Sciences

The chemical composition of the boundary layer in snow covered regions is impacted by chemistry in the snowpack via uptake, processing, and emission of atmospheric trace gases. We use the coupled one-dimensional (1-D) snow chemistry and atmospheric boundary layer model MISTRA-SNOW to study the impact of snowpack chemistry on the oxidation capacity of the boundary layer. The model includes gas phase photochemistry and chemical reactions both in the interstitial air and the atmosphere. While it is acknowledged that the chemistry occurring at ice surfaces may consist of a true quasi-liquid layer and/or a concentrated brine layer, lack of additional knowledge …


Ionospheric Signatures Of Tohoku-Oki Tsunami Of March 11, 2011: Model Comparisons Near The Epicenter, David A. Galvan, Attila Komjathy, Michael P. Hickey, Philip Stephens, Jonathan Snively, Y. Tony Song, Mark D. Butala, Anthony J. Mannucci 2012 RAND Corporation

Ionospheric Signatures Of Tohoku-Oki Tsunami Of March 11, 2011: Model Comparisons Near The Epicenter, David A. Galvan, Attila Komjathy, Michael P. Hickey, Philip Stephens, Jonathan Snively, Y. Tony Song, Mark D. Butala, Anthony J. Mannucci

Publications

We observe ionospheric perturbations caused by the Tohoku earthquake and tsunami of March 11, 2011. Perturbations near the epicenter were found in measurements of ionospheric total electron content (TEC) from 1198 GPS receivers in the Japanese GEONET network. For the first time for this event, we compare these observations with the estimated magnitude and speed of a tsunami-driven atmospheric gravity wave, using an atmosphere-ionosphere-coupling model and a tsunami model of sea-surface height, respectively. Traveling ionospheric disturbances (TIDs) were observed moving away from the epicenter at approximate speeds of 3400 m/s, 1000 m/s and 200–300 m/s, consistent with Rayleigh waves, acoustic …


Halogen Activation Via Interactions With Environmental Ice And Snow In The Polar Lower Troposphere And Other Regions, J. P. D. Abbatt, J. L. Thomas, K. Abrahamsson, Chris Boxe, A. Granfors, A. E. Jones, M. D. King, A. Saiz-Lopez, P. B. Shepson, J. Sodeau, D. W. Toohey, C. Toubin, R. von Glasow, S. N. Wren, X. Yang 2012 University of Toronto

Halogen Activation Via Interactions With Environmental Ice And Snow In The Polar Lower Troposphere And Other Regions, J. P. D. Abbatt, J. L. Thomas, K. Abrahamsson, Chris Boxe, A. Granfors, A. E. Jones, M. D. King, A. Saiz-Lopez, P. B. Shepson, J. Sodeau, D. W. Toohey, C. Toubin, R. Von Glasow, S. N. Wren, X. Yang

Publications and Research

The role of ice in the formation of chemically active halogens in the environment requires a full understanding because of its role in atmospheric chemistry, including controlling the regional atmospheric oxidizing capacity in specific situations. In particular, ice and snow are important for facilitating multiphase oxidative chemistry and as media upon which marine algae live. This paper reviews the nature of environmental ice substrates that participate in halogen chemistry, describes the reactions that occur on such substrates, presents the field evidence for ice-mediated halogen activation, summarizes our best understanding of ice-halogen activation mechanisms, and describes the current state of modeling …


Near-Real-Time Global Biomass Burning Emissions Product From Geostationary Satellite Constellation, Xiaoyang Zhang, Shobha Kondragunta, Jessica Ram, Christopher Schmidt, Ho-Chung Huang 2012 South Dakota State University

Near-Real-Time Global Biomass Burning Emissions Product From Geostationary Satellite Constellation, Xiaoyang Zhang, Shobha Kondragunta, Jessica Ram, Christopher Schmidt, Ho-Chung Huang

GSCE Faculty Publications

Near-real-time estimates of biomass burning emissions are crucial for air quality monitoring and forecasting. We present here the first near-real-time global biomass burning emission product from geostationary satellites (GBBEP-Geo) produced from satellite-derived fire radiative power (FRP) for individual fire pixels. Specifically, the FRP is retrieved using WF_ABBA V65 (wildfire automated biomass burning algorithm) from a network of multiple geostationary satellites. The network consists of two Geostationary Operational Environmental Satellites (GOES) which are operated by the National Oceanic and Atmospheric Administration, the Meteosat second-generation satellites (Meteosat-09) operated by the European Organisation for the Exploitation of Meteorological Satellites, and the Multifunctional Transport …


Droughtscape- Summer 2012, National Drought Mitigation Center 2012 University of Nebraska-Lincoln

Droughtscape- Summer 2012, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

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


Optimal Control Of Katabatic Flows Within Canopies, Hongbin Chen, Chuixiang Yi 2012 CUNY Queens College

Optimal Control Of Katabatic Flows Within Canopies, Hongbin Chen, Chuixiang Yi

Publications and Research

What slope angle favours the development of katabatic flow is still an open question. Some studies have clarified that katabatic winds are stronger on steep slopes, while others have demonstrated that katabatic winds are stronger on gentle slopes. Here, we explore the control mechanisms of katabatic flow using a simplified theoretical model in an attempt to clarify the causes of the paradoxical findings. Our results indicate that optimal conditions for katabatic flows within canopies are synergistically controlled by terrain angle, canopy structure and thermal condition through a simple equation:

LcVT-2 sin3 α = b,

where …


Life Cycle Boundaries And Greenhouse Gas Emissions From Beef Cattle, Quentin M. Dudley 2012 University of Nebraska-Lincoln

Life Cycle Boundaries And Greenhouse Gas Emissions From Beef Cattle, Quentin M. Dudley

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Beef cattle are estimated to directly contribute 26% of U.S. agricultural greenhouse gas (GHG) emissions, and future climate change policy may target reducing these emissions. Life cycle assessment (LCA) of GHG emissions from U.S. feedlot beef cattle was conducted to compare methods of the U.S. Environmental Protection Agency (EPA) with a more complete evaluation of emissions. The inclusion of emissions from crop production for feed, associated land use change, and other minor factors nearly doubled GHG emissions associated with beef feedlots from the EPA Annual Inventory estimate of 1611 kgCO2e hd-1 yr-1 to 3182 ± 167 …


Upgraded Alo Rayleigh Lidar System And Its Improved Gravity Wave Measurements, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham 2012 Utah State University

Upgraded Alo Rayleigh Lidar System And Its Improved Gravity Wave Measurements, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham

Leda Sox

The Rayleigh-Scatter lidar system at the Atmospheric Lidar Observatory (ALO) on the Utah State campus is currently going through a series of upgrades to significantly improve its observational abilities. A specific objective of these upgrades is to expand the altitude range over which backscattered photons can be collected. A second objective is to increase the sensitivity of the instrument to be able to analyze the raw data at finer temporal and/or spatial resolutions. By measuring relative densities, the system will be able to produce absolute temperatures and relative density perturbations, which illustrate gravity wave structures. Gravity wave studies will significantly …


Upgraded Alo Rayleigh Lidar System And Its Improved Gravity Wave Measurements, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham 2012 Utah State University

Upgraded Alo Rayleigh Lidar System And Its Improved Gravity Wave Measurements, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham

Graduate Student Posters

The Rayleigh-Scatter lidar system at the Atmospheric Lidar Observatory (ALO) on the Utah State campus is currently going through a series of upgrades to significantly improve its observational abilities. A specific objective of these upgrades is to expand the altitude range over which backscattered photons can be collected. A second objective is to increase the sensitivity of the instrument to be able to analyze the raw data at finer temporal and/or spatial resolutions. By measuring relative densities, the system will be able to produce absolute temperatures and relative density perturbations, which illustrate gravity wave structures. Gravity wave studies will significantly …


Estimating Annual Precipitation For The Colorado River Basin Using Oceanic-Atmospheric Oscillations, Ajay Kalra, Sajjad Ahmad 2012 University of Nevada, Las Vegas

Estimating Annual Precipitation For The Colorado River Basin Using Oceanic-Atmospheric Oscillations, Ajay Kalra, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Estimating long-lead time precipitation under the stress of increased climatic variability is a challenging task in the field of hydrology. A modified Support Vector Machine (SVM) based framework is proposed to estimate annual precipitation using oceanic-atmospheric oscillations. Oceanic-atmospheric oscillations, consisting of Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), Atlantic Multidecadal Oscillation (AMO), and El Niño–Southern Oscillation (ENSO) for a period of 1900–2008, are used to generate annual precipitation estimates with a 1 year lead time. The SVM model is applied to 17 climate divisions encompassing the Colorado River Basin in the western United States. The overall results revealed that …


Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock 2012 Air Force Institute of Technology

Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock

Theses and Dissertations

Branch points arise in optical transmissions due to strong atmospheric turbulence, long propagation paths, or a combination of both. Unfortunately, these conditions are very often present in desired operational scenarios for laser weapon systems, optical communication, and covert imaging, which suffer greatly when traditional adaptive optics systems either cannot sense branch points or implement non-optimal methods for sensing and correcting branch points. Previous research by Pellizzari presented a thorough analysis of various novel branch point tolerant reconstructors in the absence of noise. In this research a realistic model of the Air Force Institute of Technology's adaptive optics system is developed …


Ionospheric Plasma Transport And Loss In Auroral Downward Current Regions, M. Zettergren, J. L. Semeter 2012 Embry-Riddle Aeronautical University

Ionospheric Plasma Transport And Loss In Auroral Downward Current Regions, M. Zettergren, J. L. Semeter

Publications

A detailed study of the effects of auroral current systems on thermal ionospheric plasma transport and loss is conducted using a new ionospheric model. The mathematical formulation of the model is a variation on the 5‐moment approximation which describes the temporal evolution of density, drift, and temperature for five different ion species in two spatial dimensions. The fluid system is closed through a 2‐D electrostatic treatment of the auroral currents. This model is used to examine the interplay between ion heating, perpendicular transport, molecular ion generation, and type‐1 ion upflows in a self‐consistent way for the first time. Simulations confirm …


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