Wednesdays at 12:45 p.m. – 1:45 p.m.
(UNLESS OTHERWISE NOTED.)
1/11/2017 — Air Quality Impacts from Prescribed Burning in the Southeastern U.S. – Karsten Baumann (ARA RTP Office), [V/C Mike Newchurch]
Research Relevance: Air pollution
Fire plays an important role in the ecological landscape of the South-Eastern United States, where prescribed burning (PB) is employed to manage more than 8 million acres of land every year. The evolution of fire emissions in the atmosphere due to gas/particle partitioning and photo-oxidation can substantially alter the composition of gas and particle constituents, which in turn can form secondary pollutants both in the gas-phase (e.g. ozone) and particle-phase (SOA). Assessing SOA from PB is difficult since the traditional understanding of SOA formation is insufficient to explain OA observations in photo-chemically aging smoke plumes. This talk will present results from field experiments and modeling exercises, a) characterizing the complexity of the PB emission source and b) estimating the air quality impact of the PB emissions on the local to sub-regional scales. A field experiment conducted as part of the DoD-sponsored Defense Coastal/Estuarine Research Program, demonstrates the capability of following a typical real-world PB plume during its atmospheric dispersion by measuring the physical and chemical characteristics of the emissions on the ground and above the tree canopy, employing a combination of qualified and tested tools such as highly mobile ground sampling platforms and a tethered balloon system. The modeling exercise investigates the sensitivity of ambient PM2.5 to various fire and meteorological parameters in a spatial setting that is typical for the southeastern US, using the method of principle components regression. PM2.5 showed significant sensitivity to PB: 3.6 ±2.2 µg m-3 per 1000 acres burned at the investigated distance scale of ~10-50 km. Applying this sensitivity to the available activity data, revealed a PB source contribution to measured PM2.5 of up to 25%. These results will be discussed in light of the land manager’s desire to minimize PB smoke impacts.
1/18/2017 — Assessing the Equity of Access to Greener Buildings: LEED-Certified Schools & Libraries, Their Surrounding Neighborhood and Who owns Them. – Shuang Zhao (UAH ATS & Political Science), [V/C John Mecikalski]
Research Relevance: Energy, people and sustainability topics
The Environmental Justice (EJ) literature generally focuses on negative environmental externalities and disamenities found around certain types of demographic conditions such as poor and ethnic groups. Methodologies to identify the (potentially disproportionate) relationships between environmental risks and poor and ethnic minority groups compare demographic characteristics in communities affected by environmental risks or that host noxious facilities with those communities that do not host such facilities. Communities are typically defined by counties, postal zip codes, census tracts, or other units based on a geographic information system. A very large literature of empirical analyses of the relationships between demographics and environmental burdens takes a prominent position within the enormous EJ literature. In contrast, very little research in EJ has investigated the other side of the story – whether positive environmental conditions – amenities – disproportionally favor white and affluent groups. In addition, while EJ studies typically focus on race and economic class groups, few have focused on disaggregated age groups, such as children’s exposure to environmental risks. In this analysis, we take advantage of public and private datasets covering all of the United States to analyze whether household demographics of communities hosting green buildings differ from those lacking these amenities. We pay special attention to public schools, green or not, as key institutions for a neighborhood as well as sites with particularly intense exposure for neighborhood children. We examine new construction certified as “green” under the US Green Building Council’s Leadership in Energy & Environmental Design (LEED) program, the leading certifying program in the U.S. Leveraging a dataset of LEED-certified green buildings in combination with data affords us a unique opportunity to examine whether positive environmental externalities and amenities are located disproportionately in white and affluent communities. This study also advances the methodology of defining communities in EJ studies, which typically adopts a buffer analysis. We validate the correct communities that are influenced by environmental amenities by comparing buffer results with theisian polygon analysis. The result obtained from ARCGIS analysis will then be compared with the actual school enrollments data.
Because this is a rare opportunity to present her research, Dr. Zhao will also provide two examples of her other research projects during the presentation.
 The preoccupation in the EJ literature with environmental burdens in part reflects some historical context and partly reflects a particular framing (i.e., disamenities are merely the absence of amenities, local public bads the inverse of public goods). Accordingly, some empirical studies of the distribution of environmental amenities and positive externalities can be found in literatures not labeled “EJ” or directly situated within that discourse.
1/25/2017 — NO SEMINAR – AMS Annual Meeting
2/1/2017 — Probing Interfacial Chemistry: Heterogeneous Oxidations in the Environment – Marcelo Guzman (University of Kentucky), [V/C Shanhu Li]
Research Relevance: Atmospheric Chemistry
Heterogeneous reactions occurring at the air-water interface may proceed with different rates and mechanisms from those typical of reactions in the gas-phase and (bulk) water. Ion properties and concentration effects of naturally occurring chemical species create inhomogeneous gradients at the interface, as observed by mass spectrometry (MS) during the fractionation of anions from aerosolized solutions. The enrichment of anions at the air-water interface depends on the size of ions and varies in the presence of surfactants because of different energy stabilization interactions. In this seminar, experiments exploring reactions at the air-water interface will be presented: (1) the heterogeneous oxidation of iodide in sea spray with global implications to the loss of ozone, and (2) the competitive loss of biomass burning probes by OH-initiated versus direct ozonolysis reactions. The ultrafast oxidation of iodide (I–) by 50 ppbv O3 at the air-water interface produces hypoiodous acid (HIO), iodite (IO2–), iodate (IO3–), triiodide (I3–), and molecular iodine (I2). The produced HIO and I2 are transferred to the gas-phase and participate directly in the destruction of tropospheric ozone over the open ocean. A 28 % enhancement in the uptake of O3(g) is observed at the air-water interface for increasing concentration of alkali halide salt from 10 nM to 100 μM. Finally, the attack of OH radicals on aromatic hydrocarbons emitted during combustion and biomass burning produces mono- and poly-hydroxylated aromatic compounds. A different degradation pathway exists at the air-water interface, where oxo- and di-carboxylic acids of low molecular weight (LMW) are formed by direct ozonolysis of poly-hydroxylated aromatic compounds. MS measurements confirm secondary processing showing the production of low molecular weight carboxylic acids. The proposed pathways can contribute precursors to aqueous SOA (AqSOA) formation.
2/8/2017 — Intraseasonal Variability in the Structure and Lightning Production of Tropical MCSs – Katrina Virts (USRA-NPP) [V/C John Mecikalski]
Research Relevance: Lightning, tropical meteorology, mesoscale convective systems
2/15/2017 — Research at the Surface Dynamics Lab: From Global to Reach Scale Analysis of Ravine Dynamics – Sagy Cohen (Dept. of Geography, University of Alabama), [V/C Brad Zavodsky]
Research Relevance: Remote sensing and modeling
2/22/2017 — The Role of Volcanic Ash in Lightning Discharge During Explosive Eruptions – Dr. Kimberly Genareau, (University of Alabama), [V/C Larry Carey]
Research Relevance: Lightning research, volcanogy
3/1/2017 — Fire Weather: Research Challenges and Opportunities – Alan Srock(St. Cloud State University), [V/C John Mecikalski, Emily Berndt]
Research Relevance: Fire weather research
3/8//2017 —Understanding the Surprising Variation in Storm Charge Structures on 4 June 2012 over the West Texas Lightning Mapping Array – Vanna Chmielewski (Texas Tech University), [V/C Chris Schultz]
3/15/2017 — NO SEMINAR – Spring Break
3/22/2017 — Did Ancient Costa Ricans form Alliances to Mitigate Environmental Hazards? – Payson Sheets (University of Colorado, Boulder), [V/C Tom Sever]
Research Relevance: Archeology and Remote Sensing
Multidisciplinary research near Arenal Volcano in Costa Rica, with Dr. Thomas Sever (NASAàUAH) discovered many linear anomalies in analog and digital remote sensing data. Ground truthing excavations divulged many were processional pathways linking villages with their cemeteries a few kilometers away. The earliest processional pathways date to about 500 BC. Later villages on the Caribbean and the Pacific sides apparently shared a large cemetery atop the Continental Divide. Villages on the Caribbean side faced numerous explosive eruptions from the hyperactive Arenal Volcano. Villages on the much-dryer Pacific drainage faced occasional droughts. With Dr. Sever we presently are exploring the possibility that marriage and other alliances linking villages with such different threats could have provided temporary refuge until they could reoccupy their villages, and resume their pilgrimages. We will be conducting fieldwork in June-August this year, and hopefully next year.
3/29/2017 — The Green at a Steep Price – Ramakrishna Nemani (NASA Advanced Supercomputing Division, Ames Research Center), [V/C Bill Crosson]
Research Relevance: NASA applied science
4/5/2017 —The Usage of 3D City Models in Urban Energy Analysis – Application in Smart Cities Approaches – Jochen Wendel (EIFER, European Institute for Energy Research), [V/C Leiqui Hu]
Research Relevance: Urban energy analysis
4/12/2017 — Let it Rain and Snow: Global Precipitation Measurements for Science and Society – Gail S. Jackson (GPM Project Scientist), [V/C Walt Petersen]
Research Relevance: GPM science; CaPMM Lead
4/19/2017 — Climate and Vector – borne Disease Research at NCAR – Andrew Monaghan (NCAR), [V/C Leiqui Hu]
Research Relevance: Climate and human health
4/26/2017 — ATS 781 Course Presenters – ATS Department [V/C John Mecikalski]
Research Relevance: Mixed topics
5/3/2017 — What we do not Measure Affects what we see – Thoughts on Sampling Uuncertainty in Satellite Sounding Applications – Nadia Smith (Science Technology Corporation, Inc.), [V/C Emily Berndt]
Research Relevance: CrIS Hyper-spectral IR retrievals