Atmospheric Sciences Commons^™

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day and with great …

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

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

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; …

Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan

OES Faculty Publications

Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO₂ (pCO₂) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO₃ -], ammonium [NH₄ +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO₂. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d …

Intercomparison And Evaluation Of Satellite Peroxyacetyl Nitrate Observations In The Upper Troposphere-Lower Stratosphere, Richard J. Pope, Nigel A. D. Richards, Martyn P. Chipperfield, David P. Moore, Sarah A. Monks, Stephen R. Arnold, Norbert Glatthor, Michael Kiefer, Tom J. Breider, Jeremy J. Harrison, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Peroxyacetyl nitrate (PAN) is an important chemical species in the troposphere as it aids the long-range transport of NO_x and subsequent formation of O₃ in relatively clean remote regions. Over the past few decades observations from aircraft campaigns and surface sites have been used to better understand the regional distribution of PAN. However, recent measurements made by satellites allow for a global assessment of PAN in the upper troposphere-lower stratosphere (UTLS). In this study, we investigate global PAN distributions from two independent retrieval methodologies, based on measurements from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument, on …

The Use Of Remote Sensing Technologies And Models To Study Pollutants In Pdn Region, Suhail Mahmud

Open Access Theses & Dissertations

Using a suite of modeling techniques and instrumentation we study the atmospheric pollutants in the PdN Region. The first objective of this work was to measure hemi-spherically integrated, spectrally resolved solar photon flux (actinic flux) between the wavelengths 300 and 700 nm, and use the measured actinic flux to improve air quality simulations. Actinic flux was measured in the PdN region in order to calculate photolysis rate coefficients for different pollutants. The improved photolysis rate coefficients were then integrated into a photochemical air quality model (CAMx) in order to improve air quality forecasting. We present the simulations performed for a …

The Tropical Cyclone Diurnal Cycle, Jason Paul Dunion

Legacy Theses & Dissertations (2009 - 2024)

The research presented in this thesis explores a phenomenon referred to as the tropical cyclone (TC) diurnal cycle (TCDC) and presents satellite, numerical modeling, and observational perspectives pertaining to how it can be monitored, its evolution in time and space, its relevance to TC structure and intensity, and how it manifests in numerical simulations of TCs. Infrared satellite imagery was developed and used to investigate diurnal oscillations in TCs and finds a diurnal pulsing pattern that occurs with notable regularity through a relatively deep layer from the inner core to the surrounding environment. A combination of satellite, numerical model simulations, …

Understanding The Dependence Of Radiative Feedbacks And Clouds On The Spatial Structure Of Ocean Heat Uptake, Lance Rayborn

Legacy Theses & Dissertations (2009 - 2024)

Ocean heat uptake and radiative forcing are important for understanding transient climate change. Differences in efficacy of ocean heat uptake (suppression of surface warming per unit energy flux into the deep oceans relative to CO2 forcing) account for a substantial fraction of the spread in transient warming between models. Rose et al. (2014) studied the dependence of efficacy on the spatial pattern of ocean heat uptake in an ensemble of aquaplanet simulations with prescribed ocean heat uptake, and found large differences in model responses to high versus low latitude uptake. This study accurately quantifies these model responses through the use …

Examination Of Water Vapor Characteristics During The 2013 Colorado Flood, Hannah Kristine Huelsing

Legacy Theses & Dissertations (2009 - 2024)

During September 9-16, 2013, the Front Range region of Colorado experienced heavy rainfall which resulted in severe flooding. Precipitation totals during the event exceeded 450mm in Boulder, Colorado, 9 lives were lost, and damages to public and private properties were estimated to be over $2 billion. This study analyzes the characteristics of water vapor surrounding the event, including the abnormality of total column water vapor, the sources of moisture, and the relationship between water vapor and precipitation characteristics. It was found that the atmosphere was very near saturation during the duration of the event and monthly-averaged precipitable water (PW) was …

Air-Sea Carbon Dioxide Exchange In The Southern Ocean And Antarctic Sea Ice Zone, Brian Butterworth

Legacy Theses & Dissertations (2009 - 2024)

The Southern Ocean is an important part of the global carbon cycle, responsible for roughly half of the carbon dioxide (CO2) absorbed by the global ocean. The air-sea CO2 flux (Fc) can be expressed as the product of the water-air CO2 partial pressure difference (ΔpCO2) and the gas transfer velocity (k), an exchange coefficient which represents the efficiency of gas exchange. Generally, Fc is negative (a sink) throughout the Southern Ocean and Antarctic sea ice zone (SIZ), but uncertainty in k has made it difficult to develop an accurate regional carbon budget. Constraining the functional dependence of k on wind …

Chilean Coastal Orographic Precipitation Experiment : A Tale Of Two Rain Regimes, Adam Massmann

Legacy Theses & Dissertations (2009 - 2024)

The Chilean Coastal Orographic Precipitation Experiment Pilot Project (CCOPE-2015) was an exploratory field campaign to better understand the mechanisms of orographic precipitation enhancement in the Nahuelbuta Mountains of Southern Chile (38 deg. S.). Observations collected include: (1) surface rainfall from a network of 10 data logging rain gauges, (2) vertical precipitation profiles from a pair of K-band Micro Rain Radars, (3) rain drop size distributions from an optical disdrometer, (4) upstream wind and thermodynamic profiles from radiosonde launches, and (5) aerosol number concentration and size distribution measurements from a condensation particle counter and an ultra-high sensitivity aerosol spectrometer.

Hydroclimate Changes In The South-Central Great Plains Of The United States : A Synoptic Approach, Pawel Slaski

Legacy Theses & Dissertations (2009 - 2024)

Hydroclimate changes over the Southern Central Great Plains (SCGP) of the United States have been occurring throughout the last century. These changes have had a major impact on the local ecosystems, agriculture, and human society in the region by, e.g., producing a higher frequency of drought over the last century. Climate models project further increases of drought in the 21st century over this region under increasing greenhouse gases. This study analyzes climate model simulations to examine changes in synoptic conditions associated with the projected drought increases over the SCGP. Synoptically, mesoscale convective complexes (MCCs) produce a large portion of the …

The Network Average Gust Factor, Its Measurement And Environmental Controls, And Role In Gust Forecasting, Alexander Austin Gallagher

Legacy Theses & Dissertations (2009 - 2024)

There exists a strong, well documented linear relationship between network averaged sustained (or mean) wind and gust speeds within the San Diego Gas and Electric (SDGE) mesonet that is characterized by the slope of the linear regression between the two known as the network average gust factor (GF). The network average GF potentially contains information on the average obstruction of the stations within the network and when paired with numerical model output, may be used for gust prediction. Using the network average GF for gust prediction can also result in the correction of biases due to poorly resolved terrain or …

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

Sensitivity Of Maize Yield Potential To Regional Climate In The Southwestern U.S., Seung Hee Kim, Boksoon Myoung, David Stack, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

The sensitivity of maize yields to the regional climate in the Southwestern U.S. (SWUS) has been investigated by using the Agricultural Production Systems sIMulator (APSIM) model in conjunction with meteorological forcings [daily maximum and minimum temperature (Tmax and Tmin), precipitation, and radiation] from the North American Regional Reanalysis (NARR) dataset. Sensitivity experiments showed that potential crop production responded nonlinearly to variations in Tmax, Tmin, and downwelling solar radiation at the surface. Mean annual yield potential (Yp) was changed by -3.0 and 1.79 Mg ha-1 for the +1 and -1 standard deviations (σ) of Tmax variation for entire the SWUS. The …

Data From: How Uncertainty In The Neutral Wind Limits The Accuracy Of Ionospheric Modeling And Forecasting, Michael David, Jan Sojka, Robert W. Schunk

Browse all Datasets

Output files from runs of the TDIM ionospheric model used for the figures and calculations in the article in JGR Space Physics.

Global Stratospheric Measurements Of The Isotopologues Of Methane From The Atmospheric Chemistry Experiment Fourier Transform Spectrometer, Eric M. Buzan, Chris A. Beale, Chris. D. Boone, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

This paper presents an analysis of observations of methane and its two major isotopologues, CH₃D and ¹³CH₄, from the Atmospheric Chemistry Experiment (ACE) satellite between 2004 and 2013. Additionally, atmospheric methane chemistry is modeled using the Whole Atmospheric Community Climate Model (WACCM). ACE retrievals of methane extend from 6 km for all isotopologues to 75 km for ¹²CH₄, 35 km for CH₃D, and 50 km for ¹³CH₄. While total methane concentrations retrieved from ACE agree well with the model, values of δD-CH₄ and δ¹³C-CH …

Detailed Source-Specific Molecular Composition Of Ambient Aerosol Organic Matter Using Ultrahigh Resolution Mass Spectrometry And H Nmr, Amanda S. Willoughby, Andrew S. Wozniak, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Organic aerosols (OA) are universally regarded as an important component of the atmosphere that have far-ranging impacts on climate forcing and human health. Many of these impacts are related to OA molecular characteristics. Despite the acknowledged importance, current uncertainties related to the source apportionment of molecular properties and environmental impacts make it difficult to confidently predict the net impacts of OA. Here we evaluate the specific molecular compounds as well as bulk structural properties of total suspended particulates in ambient OA collected from key emission sources (marine, biomass burning, and urban) using ultrahigh resolution mass spectrometry (UHR-MS) and proton nuclear …

Upper Tropospheric Water Vapour Variability At High Latitudes- Part 1: Influence Of The Annular Modes, Christopher E. Sioris, Jason Zou, David A. Plummer, Chris D. Boone, C. Thomas Mcelroy, Patrick E. Sheese, Omid Moeini, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Seasonal and monthly zonal medians of water vapour in the upper troposphere and lower stratosphere (UTLS) are calculated for both Atmospheric Chemistry Experiment (ACE) instruments for the northern and southern high-latitude regions (60-90° N and 60-90°S). Chosen for the purpose of observing high-latitude processes, the ACE orbit provides sampling of both regions in 8 of 12 months of the year, with coverage in all seasons. The ACE water vapour sensors, namely MAESTRO (Measurements of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) and the Fourier Transform Spectrometer (ACE-FTS) are currently the only satellite instruments that can probe from …