Atmospheric Sciences Commons^™

Influence Of Atmospheric Circulation On Severe Flooding In The Atacama Desert, Jonathan Degraw

The Journal of Purdue Undergraduate Research

No abstract provided.

High Wind Alerts: A System Created With Observations From The X-Band Teaching And Research Radar, Lauren Warner

The Journal of Purdue Undergraduate Research

Following the August 13, 2011, Indiana State Fair stage collapse tragedy, caused by a wind gust from an approaching thunderstorm, Purdue University enforced a wind speed restriction of 30 mph (13 m s-1) for tents at outdoor events. During these events, volunteers stand outside with handheld anemometers, measuring and reporting when the wind speeds exceed this limit. In this study, we report testing of a new system to automate high-wind alerts based on observations from a Doppler radar, the X-band Teaching and Research Radar (XTRRA), near Purdue’s campus. XTRRA scans over campus at low elevations approximately every 5 minutes. Using …

Long‐Term Variations Of Quasi‐Trapped And Trapped Electrons In The Inner Radiation Belt Observed By Demeter And Sampex, Kun Zhang, Xinlin Li, Zheng Xiang, Leng Ying Khoo, Hong Zhao, Mark D. Looper, Michael A. Temerin, Jean-Andre Sauvaud

Publications

Electrons in the Earth's radiation belts can be categorized into three populations: precipitating, quasi‐trapped, and trapped. We use data from the Detection of Electro‐Magnetic Emissions Transmitted from Earthquake Regions (DEMETER) and Solar, Anomalous, and Magnetospheric Particle Explorer satellite (SAMPEX) missions and from ground‐based neutron monitors (NM) and sunspot observations to investigate the long‐term variation of quasi‐trapped and trapped sub‐MeV electrons on different L shells in the inner belt. DEMETER and SAMPEX measurements span over 17 years and show that at L ≤ 1.14 the electron flux is anticorrelated with sunspot number, but proportional to the cosmic ray intensity represented by …

Long Term Air Quality Analysis In Reference To Thermal Power Plants Using Satellite Data In Singrauli Region, India, H. K. Romana, Ramesh P. Singh, D. P. Shukla

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The exponentially growing population and related anthropogenic activities have led to modifications in local environment. The change in local environment, evolving pattern of land use, concentrations of greenhouse gases and aerosols alter the energy balance of our climate system. This alteration in climate is leading to pre-mature deaths worldwide. This study analyses the air quality of Singrauli region, Madhya Pradesh, India for the past 15 years. Otherwise known as Urjanchal “the energy capital” of India has been declared as critically polluted by CPCB. The study provides an updated list of thermal power plants in the study area and their emission …

Life In Hampton Roads Survey: Hurricanes And Covid-19, News @ Odu

News Items

No abstract provided.

Hail Detection Using Dual Polarization Weather Radar, Alfonso Ladino Rincon

International Programs

This poster highlights how active remote sensors such as weather radar are completely useful for hail detection given its feature and the information they produce. Hail detection is already well studied by the atmospheric scientific community and dual polarimetric variables values for hail signature are presented according to those advances. Then, a supervised classification technique is showed to illustrated how machine learning can be integrated to radar information for automatic hail detection. However, this fuzzy logic algorithm has the capability to distinguish between meteorological and non-meteorological echoes. This automatic information might help forecasters from National Weather Services – NWS to …

The Source Detection Of 28 September 2018 Sulawesi Tsunami By Using Ionospheric Gnss Total Electron Content Disturbance, Jann-Yenq Liu, Chi-Yen Lin, Yuh-Ing Chen, Tso-Ren Wu, Meng-Ju Chung, Tien-Chi Liu, Yu-Lin Tsai, Loren C. Chang, Chi-Kuang Chao, Dimitar Ouzounov, Katsumi Hattori

Mathematics, Physics, and Computer Science Faculty Articles and Research

The 28 September 2018 magnitude Mw7.8 Palu, Indonesia earthquake (0.178° S, 119.840° E, depth 13 km) occurred at 10:02 UTC. The major earthquake triggered catastrophic liquefaction, landslides, and a near-field tsunami. The ionospheric total electron content (TEC) derived from records of 5 ground-based global navigation satellite system (GNSS) receivers is employed to detect tsunami traveling ionospheric disturbances (TTIDs). In total, 15 TTIDs have been detected. The ray-tracing and beamforming techniques are then used to find the TTID source location. The bootstrap method is applied in order to further explore the possible location of the tsunami source based on results of …

Application Of Autoencoders For Latent Pattern Analysis In Image Time Series, Jiena He

Sustainability and Social Justice

The Earth system is considered to possess certain modes - preferred patterns of variability that can represent the latent structure of the climate system, also known as teleconnections. There are approaches to discover these patterns, Principal Components Analysis and Empirical Orthogonal Teleconnection (EOT) analysis. However, while the latter is very effective, it is computationally intensive. An autoencoder is an unsupervised neural network that learns an efficient neural representation of input data. It is considered as a dimensionality reduction tool that is highly similar to PCA and EOT. The hidden layer of an autoencoder represents the most significant information of the …

The Post-Wildfire Impact Of Burn Severity And Age On Black Carbon Snow Deposition And Implications For Snow Water Resources, Cascade Range, Washington, Ted M. Uecker, Susan D. Kaspari, Keith N. Musselman, S. Mckenzie Skiles

Geological Sciences Faculty Scholarship

Wildfires in the snow zone affect ablation by removing forest canopy, which enhances surface solar irradiance, and depositing light absorbing particles [LAPs, such as black carbon (BC)] on the snowpack, reducing snow albedo. How variations in BC deposition affects post-wildfire snowmelt timing is poorly known and highly relevant to water resources. We present a field-based analysis of BC variability across five sites of varying burn age and burn severity in the Cascade Range, Washington State, United States. Single particle soot photometer (SP2) analyses of BC snow concentrations were used to assess the impact of BC on snow albedo, and radiative …

Accumulation Of Polar Vorticity On Giant Planets: Towards A Three-Dimensional Theory, Shawn R. Brueshaber

Dissertations

My research investigates the polar atmospheric dynamics of the giant planets: Jupiter and Saturn (gas giants), and Uranus and Neptune (ice giants). I conduct my research modifying and applying the Explicit Planetary Isentropic Coordinate global circulation code to model the polar regions of the four giant planets.

The motivation behind my research is to uncover the reason why giant planet polar atmospheric dynamics differ. Jupiter features multiple circumpolar cyclones arranged in geometrical configurations, whereas Saturn features a single pole-centered cyclone. Uranus and Neptune also appear to have single pole-centered cyclones, albeit, larger than those on Saturn. …

A Comprehensive Study Of The Short-Term Variability Of The Migrating Diurnal Tide In The Mesosphere And Lower Thermosphere., Lokupatabendige Ashan Shivantha Vitharana

Electronic Theses and Dissertations

Our ability to understand and predict space weather has become vital due to its significant societal impacts on communication, transportation, and national defense. One of the most exciting discoveries in the last decade has been the realization that tropospheric weather can strongly influence space weather. It is now recognized that the atmospheric waves (gravity waves, atmospheric tides, and planetary waves) play a key role in coupling the lower and upper atmosphere. The focus of this dissertation is to study atmospheric tides. While the climatology of tides has been extensively studied, little is known about the tidal weather (tidal variability

Climate Change And Market-Based Insurance Feedbacks, Eric R. Holley, Adam Liska, Cory Walters, Geoffrey C. Friesen, Michael Hayes, Max J. Rudolph, Donald A. Wilhite

Adam Liska Papers

Climatic events have accounted for 91% of $1.05 trillion in insured costs for global catastrophic events from 1980 to 2016. Costs are driven by socio-economic development and increased frequency and severity of climatic disasters driven by climate change. Government policies to reduce systemic risk (e.g., cap-and-trade, carbon tax) have been a predominant approach for mitigation and adaptation. Alternatively, market-based incentives for climate change adaptation and mitigation already operate via the insurance industry to lessen impacts on society. Insurance feedbacks include changes in 1) premiums and insurance policies, 2) non-coverage, and 3) policy making and litigation. Alongside government policies, insurance feedbacks …

Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas

United States Fish and Wildlife Service: Publications

Dear Colleague Letter from the American Fisheries Society to fellow scientific societies, July 25, 2020, about the urgent need for responsive collective action to mitigate impending radical climate change. Includes the Statement of World Aquatic Scientific Societies on the Need to Take Urgent Action Against Human-Caused Climate Change, Based on Scientific Evidence, emphasizing the importance of aquatic ecosystems. Includes extensive citations and notes.

"Water is the most important natural resource on Earth as it is vital for life. Aquatic ecosystems, freshwater or marine, provide multiple benefits to human society, such as provisioning of oxygen, food, drinking water, genetic resources; regulation …

Odu Professors Focus On Hurricane Planning During A Pandemic, Sherry Dibari

News Items

No abstract provided.

Observations Of An Extreme Atmospheric River Storm With A Diverse Sensor Network, B. J. Hatchett, Michael L. Kaplan, Q. Cao, P. B. Dawson, C. J. Ellis, Et Al.

Publications

Observational networks enhance real‐time situational awareness for emergency and water resource management during extreme weather events. We present examples of how a diverse, multitiered observational network in California provided insights into hydrometeorological processes and impacts during a 3‐day atmospheric river storm centered on 14 February 2019. This network, which has been developed over the past two decades, aims to improve understanding and mitigation of effects from extreme storms influencing water resources and natural hazards. We combine atmospheric reanalysis output and additional observations to show how the network allows: (1) the validation of record cool season precipitable water observations over southern …

Global Atmospheric Budget Of Acetone: Air-Sea Exchange And The Contribution To Hydroxyl Radicals, Siyuan Wang, Eric C. Apel, Rebecca H. Schwantes, Kelvin H. Bates, Daniel J. Jacob, Emily V. Fischer, Rebecca S. Hornbrook, Alan J. Hills, Louisa K. Emmons, Laura L. Pan, Shawn Honomichl, Simone Tilmes, Jean‐François Lamarque, Mingxi Yang, Christa A. Marandino, E. S. Saltzman, Warren J. De Bruyn, Sohiko Kameyama, Hiroshi Tanimoto, Yuko Omori, Samuel R. Hall, Kirk Ullmann, Thomas B. Ryerson, Chelsea R. Thompson, Jeff Peischl, Bruce C. Daube, Róisín Commane, Kathryn Mckain, Colm Sweeney, Alexander B. Thames, David O. Miller, William H. Brune, Glenn S. Diskin, Joshua P. Digangi, Steven C. Wofsy

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Acetone is one of the most abundant oxygenated volatile organic compounds (VOCs) in the atmosphere. The oceans impose a strong control on atmospheric acetone, yet the oceanic fluxes of acetone remain poorly constrained. In this work, the global budget of acetone is evaluated using two global models: CAM‐chem and GEOS‐Chem. CAM‐chem uses an online air‐sea exchange framework to calculate the bidirectional oceanic acetone fluxes, which is coupled to a data‐oriented machine‐learning approach. The machine‐learning algorithm is trained using a global suite of seawater acetone measurements. GEOS‐Chem uses a fixed surface seawater concentration of acetone to calculate the oceanic fluxes. Both …

Atmospheric Contrail Detection With A Deep Learning Algorithm, Nasir Siddiqui

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

Aircraft contrail emission is widely believed to be a contributing factor to global climate change. We have used machine learning techniques on images containing contrails in hopes of being able to identify those which contain contrails and those that do not. The developed algorithm processes data on contrail characteristics as captured by long-term image records. Images collected by the United States Department of Energy’s Atmospheric Radiation Management user facility(ARM) were used to train a deep convolutional neural network for the purpose of this contrail classification. The neural network model was trained with 1600 images taken by the Total Sky Imager(TSI) …

Glyoxal’S Impact On Dry Ammonium Salts: Fast And Reversible Surface Aerosol Browning (Raw Data), David O. De Haan Phd, Lelia N. Hawkins Phd, Margaret A. Tolbert Phd, Jean-François Doussin

Chemistry and Biochemistry: Faculty Scholarship

Alpha-dicarbonyl compounds are believed to form brown carbon in the atmosphere via reactions with ammonium sulfate (AS) in cloud droplets and aqueous aerosol particles. In this work, brown carbon formation in AS and other aerosol particles was quantified as a function of relative humidity (RH) during exposure to gas-phase glyoxal (GX) in chamber experiments. Under dry conditions (RH < 5%), solid AS, AS/glycine, and methylammonium sulfate aerosol particles brown within minutes upon exposure to GX, while sodium sulfate particles do not. When GX concentrations decline, browning goes away, demonstrating that this dry browning process is reversible. Declines in aerosol albedo are found to be a function of [GX]2, and are consistent between AS and AS/glycine aerosol. Dry methylammonium sulfate aerosol browns 4´ more than dry AS aerosol, but deliquesced AS aerosol browns much less than dry AS aerosol. Optical measurements at 405, 450, and 530 nm provide an estimated Ångstrom absorbance coefficient of -16 ±4. This coefficient and the empirical relationship between GX and albedo are used to estimate an upper limit to global radiative forcing by brown carbon formed by 70 ppt GX reacting with AS (+7.6 ´10-5 W/m2). This quantity is < 1% of the total radiative forcing by secondary brown carbon, but occurs almost entirely in the ultraviolet range.

The zipped data files are in the following formats: Igor experiments (.pxp), Word documents (.docx), Excel spreadsheets (.xlsx), organized by experiment number. “Optical” files contain cavity attenuated phase shift (CAPS) extinction, scattering and albedo data; PILS/waveguide data (experiments 1,2, and 5 only); …

Glyoxal’S Impact On Dry Ammonium Salts: Fast And Reversible Surface Aerosol Browning, David O. De Haan Phd, Lelia N. Hawkins Phd, Kevin Jansen, Hannah G. Welsh, Raunak Pednekar, Alexia De Loera, Natalie G. Jimenez, Margaret A. Tolbert Phd, Mathieu Cazaunau Phd, Aline Gratien, Antonin Bergé, Edouard Pangui, Paola Formenti, Jean-François Doussin

Chemistry and Biochemistry: Faculty Scholarship

Alpha-dicarbonyl compounds are believed to form brown carbon in the atmosphere via reactions with ammonium sulfate (AS) in cloud droplets and aqueous aerosol particles. In this work, brown carbon formation in AS and other aerosol particles was quantified as a function of relative humidity (RH) during exposure to gas-phase glyoxal (GX) in chamber experiments. Under dry conditions (RH < 5%), solid AS, AS/glycine, and methylammonium sulfate aerosol particles brown within minutes upon exposure to GX, while sodium sulfate particles do not. When GX concentrations decline, browning goes away, demonstrating that this dry browning process is reversible. Declines in aerosol albedo are found to be a function of [GX]², and are consistent between AS and AS/glycine aerosol. Dry methylammonium sulfate aerosol browns 4´ more than dry AS aerosol, but deliquesced AS aerosol browns much less than dry AS aerosol. Optical measurements at 405, 450, and 530 nm provide an …

Droughtscape, Summer 2020, National Drought Mitigation Center

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

DroughtScape, Summer 2020