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Full-Text Articles in Atmospheric Sciences

Modeling And Satellite Remote Sensing Of The Meteorological Impacts Of Irrigation During The 2012 Central Plains Drought, Clint Aegerter Jun 2016

Modeling And Satellite Remote Sensing Of The Meteorological Impacts Of Irrigation During The 2012 Central Plains Drought, Clint Aegerter

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

As irrigation is increasingly needed for agricultural production, it is becoming progressively more important to understand not only how irrigation impacts water availability, but how the introduction of this water into the soil impacts weather and climate through land-atmosphere interactions. In the summer of 2012, the Central Plains of the United States experienced one of its most severe droughts on record. This study examines the meteorological impacts of irrigation during this drought through observations and model simulations using the Community Land Model (CLM) coupled to the Weather Research and Forecasting (WRF) model. A simple parameterization of irrigation processes is added …


Umphlett Qci June 2016, Natalie Umphlett Jun 2016

Umphlett Qci June 2016, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Snowpack and Streamflow

Limited Frost Damage to Crops this Spring

Wet Conditions Cause Mixed Impacts

3-Month Precipitation and Temperature Outlooks

U.S. Seasonal Drought Outlook


Differing Roles Of The Great Plains Low-Level Jet In Producing Warm Season Precipitation Over The Central United States In 2002, Mengyuan Shang May 2016

Differing Roles Of The Great Plains Low-Level Jet In Producing Warm Season Precipitation Over The Central United States In 2002, Mengyuan Shang

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

The purpose of this research is to describe and compare different roles of the Great Plains low-level jet (GPLLJ) in producing warm season precipitation over the central United States by model simulation. After going through 35 years’ (from 1979- 2013) NCEP North American Regional Reanalysis (NARR) data, year 2002 was selected for model simulation as it contained a “wet period” (May- June) and a “dry period” (July- August). The model simulation was done by using Weather Research and Forecasting (WRF) Regional Model. In this study, the GPLLJ was defined by the low-level wind at 925 hPa. The results showed the …


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


Polarimetric Radar Signatures Of Supercell Thunderstorms In Tropical Cyclones, Emily Paltz, Matthew Van Den Broeke Apr 2016

Polarimetric Radar Signatures Of Supercell Thunderstorms In Tropical Cyclones, Emily Paltz, Matthew Van Den Broeke

UCARE: Research Products

Background It is necessary for operational meteorologists to forecast quickly and accurately when storms have the potential of producing severe weather such as tornadoes or hail. Presently, radar represents the most effective way to monitor storms in real time. The National Weather Service recently upgraded the national radar network to polarimetric capability. Much time and resources have been devoted to understanding the development of Great Plains supercells such that polarimetric radar schematics have been developed for them. Little, however, has been done for tropical cyclone supercells. In this study we wish to determine typical polarimetric radar structure for supercells in …


Effects Of Meteorological Conditions On Sulfur Dioxide Air Pollution In The North China Plain During Winter Of 2006–2015, Chase C. Calkins Mar 2016

Effects Of Meteorological Conditions On Sulfur Dioxide Air Pollution In The North China Plain During Winter Of 2006–2015, Chase C. Calkins

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

The last decade has seen frequent occurrences of severe air pollution episodes of high concentration in SO2 during winters in the North China Plain (NCP). Using satellite data from the Ozone Monitoring Instrument (OMI), chemistry transport model (GEOS-Chem) simulations, and National Center for Environmental Predication (NCEP) meteorological reanalyzes, this study examines meteorological and synoptic conditions associated with these air pollution episodes during winters of 2006-2015. OMI-based data suggest a large decrease (~30% in area average) of emission since 2010. Statistical analyzes show that meteorological conditions associated with the top 10% of OMI-based high days are found in average to …


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


Air Quality Related Values (Aqrvs) For Northern Great Plains Network (Ngpn) Parks, Effects From Ozone; Visibility Reducing Particles; And Atmospheric Deposition Of Acids, Nutrients And Toxics, Timothy J. Sullivan Mar 2016

Air Quality Related Values (Aqrvs) For Northern Great Plains Network (Ngpn) Parks, Effects From Ozone; Visibility Reducing Particles; And Atmospheric Deposition Of Acids, Nutrients And Toxics, Timothy J. Sullivan

United States National Park Service: Publications

Summary

This report describes the Air Quality Related Values (AQRVs) of the Northern Great Plains Network (NGPN). AQRVs are those resources sensitive to air quality and include streams, lakes, soils, vegetation, fish and wildlife, and visibility. This report also describes air pollutant emissions and air quality in NGPN, and their effects on AQRVs. The primary pollutants likely to affect AQRVs include nitrogen (N) and sulfur (S) compounds (nitrate [NO3-], ammonium [NH4+], and sulfate [SO42-]); ground-level ozone (O3); haze-causing particles; and airborne toxics.

The 13 parks that are included in …


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, …


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 …


Nres/Metr/Bsen 479/879: Hydroclimatology—A Peer Review Of Teaching Project Benchmark Portfolio, Francisco Munoz-Arriola Jan 2016

Nres/Metr/Bsen 479/879: Hydroclimatology—A Peer Review Of Teaching Project Benchmark Portfolio, Francisco Munoz-Arriola

UNL Faculty Course Portfolios

Rising temperatures and extreme hydrometeorological and climate events are evidences of a changing climate. An increasing population together with their demands for food, energy and water make changes in climate evidence the need to train a new generation of multidisciplinary professionals with a clear understanding of the effects of a changing climate in their activities. Historically, climate sciences were used for scientific and weather operational contexts and engineers applied stationary assumptions for multi-term planning. My goal is to identify elements built from classroom experiences about (a) the suitability of a hydroclimatology course for engineers and scientists; (b) the multidisciplinary skills; …


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


Three-Dimensional Wind Speed And Flux Measurements Over A Rain-Fed Soybean Field Using Orthogonal And Non-Orthogonal Sonic Anemometer Designs, Taylor Thomas Dec 2015

Three-Dimensional Wind Speed And Flux Measurements Over A Rain-Fed Soybean Field Using Orthogonal And Non-Orthogonal Sonic Anemometer Designs, Taylor Thomas

School of Natural Resources: Dissertations, Theses, and Student Research

The eddy covariance method for estimating fluxes of trace gases, energy and momentum in the constant flux layer above a plant canopy fundamentally relies on accurate measurements of the vertical wind speed. This wind speed is typically measured using a three-dimensional ultrasonic anemometer. Previous studies comparing anemometers with orthogonal transducer sets to those with non-orthogonal transducer sets suggest differences in measured 3D wind speed components, particularly for a vertical component. These differences, attributed to additional flow distortion caused by the non-orthogonal transducer arrangement and support structure, directly affect fluxes of trace gases, energy and momentum. A field experiment was conducted …


Umphlett Qci 2015, Natalie A. Umphlett Dec 2015

Umphlett Qci 2015, Natalie A. Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Late Hard Freeze

Late Freezes Extended Growing Season

Warm Fall Delays Bird Migrations

Monitoring Water Resources Across the Basin

3-Month Precipitation and Temperature Outlooks


Droughtscape, Fall 2015, Kelly Smith Oct 2015

Droughtscape, Fall 2015, Kelly Smith

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

Contents

Director’s column.

NDMC 20th anniversary 2

Employment opportunity

Third quarter 2015 climate summary

Third quarter 2015 impacts summary

Workshop in Ethiopia

San Antonio multi-hazard tournament

Healthy soil is drought buffer

U2U Award

Cost-benefit analysis for utilities managing drought

NDMC helps with rural poll questions on climate

Introducing our post-docs

South Korean visitors


Umphlett Qci Sept 2015, Natalie Umphlett Sep 2015

Umphlett Qci Sept 2015, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalie

Streamflow

Heavy Rains Continued

Positive and Negative Impacts to Agriculture

Persistent Smoke from Wildfires

3-Month Precipitation and Temperature Outlooks


Retrieval Of Aerosol Microphysical Properties From Aeronet Photopolarimetric Measurements, Xiaoguang Xu Aug 2015

Retrieval Of Aerosol Microphysical Properties From Aeronet Photopolarimetric Measurements, Xiaoguang Xu

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

Atmospheric aerosols play an important role in earth climate by scattering and absorbing solar and terrestrial radiation, and indirectly through altering the cloud formation, life- time, and radiative properties. However, accurate quantification of these effects is in no small part hindered by our limited knowledge about the particle size distribution (PSD) and refractive index, the aerosol microphysical properties essentially pertain to aerosol optical and cloud-forming properties. The research goal of this thesis is to obtain the aerosol microphysical properties of both fine and coarse modes from the polarimetric solar radiation measured by the SunPhotometer of the Aerosol Robotic Network (AERONET). …


Improving Nocturnal Fire Detection With The Viirs Day–Night Band, Thomas N. Polivka Jul 2015

Improving Nocturnal Fire Detection With The Viirs Day–Night Band, Thomas N. Polivka

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

As an important component in the Earth-atmosphere system, wildfires are a serious threat to life and property that—despite improving warning systems—have exacted greater costs in recent years. In addition, they impact global atmospheric chemistry by releasing potent trace gasses and aerosols. Using the Visible Infrared Imaging Radiometer Suite (VIIRS), this study investigates the adjustment of fire pixel selection criteria to include visible light signatures at night, creating the Firelight Detection Algorithm (FILDA). This allows for greatly improved detection of smaller and cooler fires from satellite observations. VIIRS scenes with coincident Advanced Spaceborne Thermal Emission and Reflection (ASTER) overpasses are examined …


Modeling Gross Primary Production Of Maize And Soybean Croplands Using Light Quality, Temperature, Water Stress, And Phenology, Anthony L. Nguy-Robertson, Andrew E. Suyker, Xiangming Xiao Jul 2015

Modeling Gross Primary Production Of Maize And Soybean Croplands Using Light Quality, Temperature, Water Stress, And Phenology, Anthony L. Nguy-Robertson, Andrew E. Suyker, Xiangming Xiao

School of Natural Resources: Faculty Publications

Vegetation productivity metrics, such as gross primary production (GPP) may be determined from the efficiency with which light is converted into photosynthates, or light use efficiency (ϵ). Therefore, accurate measurements and modeling of ϵ is important for estimating GPP in each ecosystem. Previous studies have quantified the impacts of biophysical parameters on light use efficiency based GPP models. Here we enhance previous models utilizing four scalars for light quality (i.e., cloudiness), temperature, water stress, and phenology for data collected from both maize and soybean crops at three Nebraska AmeriFlux sites between 2001 and 2012 (maize: 26 field-years; soybean: …


Droughtscape, Summer 2015, Kelly Smith Jul 2015

Droughtscape, Summer 2015, Kelly Smith

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

Contents

Director’s column

New Drought Risk Management Research Center

Second quarter 2015 climate summary

Second quarter 2015 impacts summary

Caribbean region an innovator in drought early warning

Wind River Reservation tribes move toward drought planning

Ranchers, U.S. Forest Service, University of Arizona co-develop drought plans

Summer blockbuster from CoCoRaHS: Assessing Drought in the U.S

Western states drought coordinators meet


Umphlett Qci June 2015, Natalie A. Umphlett Jun 2015

Umphlett Qci June 2015, Natalie A. Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Drought Conditions

Water Supplies Recovering

Heavy Rains Cause Flooding

Agriculture Impacts

3-Month Precipitation and Temperature Outlooks


Springtime Melt Onset On Arctic Sea Ice From Satellite Observations And Related Atmospheric Conditions, Angela C. Bliss May 2015

Springtime Melt Onset On Arctic Sea Ice From Satellite Observations And Related Atmospheric Conditions, Angela C. Bliss

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

The timing of snowmelt onset (MO) on Arctic sea ice derived from passive microwave satellite data is examined by determining the melting area (in km2) on a daily basis for the spring and summer melt season months over the 1979 – 2012 data record. The date of MO on Arctic sea ice has important implications for the amount of total solar energy absorbed by the ice-ocean system in a given year. Increasingly early mean MO dates have been recorded over the 34-year data record as evidenced by statistically significant trends of 6.6 days decade-1 over the extent …


Drougthscape, Spring 2015, Kelly Smith Apr 2015

Drougthscape, Spring 2015, Kelly Smith

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

Contents

Director’s column.

South Plains ranch workshops 3

First quarter drought summary

First quarter impacts summary

Gary’s favorite pond, D1-4

NDMC’s Haigh leads U2U pubs

SW Montana watersheds convene

Wind River monitors drought

Morocco’s new drought index

Northeast Brazil drought monitoring

EU’s drought initiative

U.S. Drought Monitor Forum

How Colorado tourism coped in 2012


Umphlett Qci March 2015, Natalie Umphlett Mar 2015

Umphlett Qci March 2015, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Mountain Snowpack

Agriculture

Recreation and Tourism

Forestry

Drought Impacts Continue

3-Month Precipitation and Temperature Outlooks

U.S. Seasonal Drought Outlook


Productivity, Absorbed Photosynthetically Active Radiation, And Light Use Efficiency In Crops: Implications For Remote Sensing Of Crop Primary Production, Anatoly A. Gitelson, Yi Peng, Timothy J. Arkebauer, Andrew E. Suyker Feb 2015

Productivity, Absorbed Photosynthetically Active Radiation, And Light Use Efficiency In Crops: Implications For Remote Sensing Of Crop Primary Production, Anatoly A. Gitelson, Yi Peng, Timothy J. Arkebauer, Andrew E. Suyker

School of Natural Resources: Faculty Publications

Vegetation productivity metrics such as gross primary production (GPP) at the canopy scale are greatly affected by the efficiency of using absorbed radiation for photosynthesis, or light use efficiency (LUE). Thus, close investigation of the relationships between canopy GPP and photosynthetically active radiation absorbed by vegetation is the basis for quantification of LUE. We used multiyear observations over irrigated and rainfed contrasting C3 (soybean) and C4 (maize) crops having different physiology, leaf structure, and canopy architecture to establish the relationships between canopy GPP and radiation absorbed by vegetation and quantify LUE. Although multiple LUE definitions are reported in the literature, …


Drougthscape, Winter 2015, Kelly Smith Jan 2015

Drougthscape, Winter 2015, Kelly Smith

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

Contents

Director’s report

Central U.S. 2012 report

October-December drought summary

2014 drought summary

Caribbean capacity building

Drought impacts in 2014

California timeline 2014

UC Davis ranching workshop

NASA SMAP data

Global drought info system

Community Capitals

Evaluation and assessment

Indicator-impact research

NDMC on YouTube


A Fast Visible Infrared Imaging Radiometer Suite Simulator For Cloudy Atmospheres, Chao Liu, Ping Yang, Steven Platnick, Kerry G. Meyer, Chenxi Wang, Shouguo Ding Jan 2015

A Fast Visible Infrared Imaging Radiometer Suite Simulator For Cloudy Atmospheres, Chao Liu, Ping Yang, Steven Platnick, Kerry G. Meyer, Chenxi Wang, Shouguo Ding

Department of Earth and Atmospheric Sciences: Faculty Publications

A fast instrument simulator is developed to simulate the observations made in cloudy atmospheres by the Visible Infrared Imaging Radiometer Suite (VIIRS). The correlated k distribution technique is used to compute the transmissivities associated with absorbing atmospheric gases. The bulk scattering properties of ice clouds are based on the ice model used for the Moderate Resolution Imaging Spectroradiometer Collection 6 ice cloud products, and those ofwater clouds are computedwith the Lorenz-Mie theory. Two fast radiative transfer models based on precomputed ice cloud look-up tables are used for the VIIRS solar and infrared channels. The accuracy and efficiency of the fast …


The Gravity Environment Of Zhouqu Debris Flow Of August 2010 And Its Implication For Future Recurrence, Diandong Ren, Lance M. Leslie, Xinyi Shen, Yang Hong, Qingyun Duan, Rezaul Mahmood, Yun Li, Gang Huang, Weidong Guo, Mervyn J. Lynch Jan 2015

The Gravity Environment Of Zhouqu Debris Flow Of August 2010 And Its Implication For Future Recurrence, Diandong Ren, Lance M. Leslie, Xinyi Shen, Yang Hong, Qingyun Duan, Rezaul Mahmood, Yun Li, Gang Huang, Weidong Guo, Mervyn J. Lynch

High Plains Regional Climate Center: Staff Publications

This study investigates the geological background of the August 7-8, 2010 Zhouqu debris flows in the northwestern Chinese province of Gansu, and possible future occurrence of such hazards in the peri-Tibetan Plateau (TP) regions. Debris flows are a more predictable type of landslide because of its strong correlation with extreme precipitation. However, two factors affecting the frequency and magnitude of debris flows: very fine scale precipitation and degree of fracture of bedrock, both defy direct observations. Annual mean Net Primary production (NPP) is used as a surrogate for regional precipitation with patchiness filtered out, and gravity satellite measured regional mass …


Development Of A Long-Term (1884-2006) Serially Complete Dataset Of U.S. Temperatures And Precipitation For Climate Services, Jinshing You, Kenneth G. Hubbard, Martha Shulski, Mark D. Svoboda, Michael J. Hayes Jan 2015

Development Of A Long-Term (1884-2006) Serially Complete Dataset Of U.S. Temperatures And Precipitation For Climate Services, Jinshing You, Kenneth G. Hubbard, Martha Shulski, Mark D. Svoboda, Michael J. Hayes

High Plains Regional Climate Center: Staff Publications

Serially complete climate datasets with no missing data are necessary for a diverse group of users working in many economic sectors. In this article we describe the procedures used to create a Serially Complete Data set (SCD) for the U.S. We include the selection criterion applied to potential SCD stations, the various procedural steps and the details applied to each step. A few observations that were not previously digitized were obtained from observers official paper reports. The methods used to estimate missing data are the Spatial Regression Test and the Inverse Distance Weighting technique. Using the criterion for selecting stations …


A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett Jan 2015

A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett

High Plains Regional Climate Center: Staff Publications

Nebraska is situated at the intersection of the northern and southern Great Plains, exhibiting a dramatic longitudinal gradient for precipitation and humidity, and benefiting from groundwater resources. The continental climate is highly variable temporally both for temperature and precipitation. Our assessment of long-term meteorological observations shows that over the last century the annual average temperature in Nebraska has warmed approximately 0.6°C, which is similar to the increase in the global average temperature over the same time period. Furthermore, we found minimum temperatures have warmed more than maximum temperatures, and winter and spring show the strongest warming. We found no significant …