Atmospheric Sciences Commons^™

Analysis Of Hurricane Track Forecast Accuracy During The 2018 Season, Jonathan D. Unger

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Hurricane track forecasting has become more accurate in recent years due to technological advances in modeling methods. However, due to the complex nature of the relationship between oceanic and atmospheric variables and hurricane tracks, noteworthy errors in track prediction, especially for predictions several days into the future, still remain. In this study, two different methods of forecasting hurricane tracks are compared. Using the four United States landfalling hurricanes of the 2018 season as a sample, the official forecast tracks published by the National Hurricane Center (NHC) and hypothetical tracks based purely on climatology were mapped simultaneously with the preliminary best …

An Overview Of Handheld Sun Photometer Measurements Of Atmospheric Aerosols In New Orleans, Louisiana: A Case Study Of The Xavier University Study Site., M. Bradley, B. Sevalia, M. Gasseller

Faculty and Staff Publications

Aerosol optical depth (AOT) was measured at Xavier University of Louisiana (XULA, 29.96ᵒ N, 90.11° W and 3m above sea level) using a GLOBE handheld sun photometer. The measurements were done at two different wavelengths, 505nm and 625nm. The measured values were used to extrapolate the AOT values for wavelengths 667nm, 551nm, 532nm and 490nm at the XULA site. The measured and calculated AOT values were then compared with values from the nearest AERONET station at Wave CIS site 6 (AERONET, 28.87ᵒ N, 90.48° W and 33m above sea level), which is 60 miles south of XULA. In this study …

Odu Expert Invited To Testify At Legislative Hearing On Coastal Resilience, Sarah Huddle

News Items

No abstract provided.

An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp

Earth and Planetary Sciences ETDs

Recent studies have shown water vapor isotopologues to be sensitive tracers of mixing processes that govern low-cloud feedback in climate models. In this study, we develop an inverse model (MBL Mix inverse model) that uses one year of isotope and humidity observations from Graciosa Island, Azores to estimate mixing for four seasons. We show the dry end-member of the model, the lower free troposphere (LFT), can be represented using Rayleigh fractionation. Isotope observations from Graciosa Island are compared to other field locations to discuss controls on isotopic variability other than mixing. Output from the MBL Mix inverse model shows the …

The Impact Of Energetic Neutral Particles Raining Down On The Thermosphere Due To Charge Exchange Reactions In The Upper Ionosphere And Polar Wind, Larry Gardner

Funded Research Records

No abstract provided.

An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp

Earth and Planetary Sciences ETDs

Recent studies have shown water vapor isotopologues to be sensitive tracers of mixing processes that govern low-cloud feedback in climate models. In this study, we develop an inverse model (MBL Mix inverse model) that uses one year of isotope and humidity observations from Graciosa Island, Azores to estimate mixing for four seasons. We show the dry end-member of the model, the lower free troposphere (LFT), can be represented using Rayleigh fractionation. Isotope observations from Graciosa Island are compared to other field locations to discuss controls on isotopic variability other than mixing. Output from the MBL Mix inverse model shows the …

Droughtscape, Fall 2019, Cory Matteson

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

Contents

From the Director

Quarterly drought summary

Quarterly drought impacts

Ranchers delayed response to drought

Drought Monitor celebrates 20 years

Drought Monitor state impact tables

Directorcontributesto U.N.droughtproject

Updated Drought Risk Atlas

New fact sheet lists recovery resources

Droughtscape, Summer 2019, Cory Matteson

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

Contents

From the Director

Quarterly drought summary

Quarterly drought impacts

NDMC welcomes African visitors

Ready for Drought game debuts

U.S. Virgin Islands added to USDM

Australian programmer visits NDMC

Upcoming events

Partnerships with NDMC extended

Evaluation Of Viirs Nightfire Product And Comparison With Modis And Viirs Active Fire Products In A Russian Gas Flaring Region, Ambrish Sharma

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

Gas flaring is a commonly used practice for disposing of waste gases emerging from industrial oil drilling and production processes. It is a serious environmental and economic hazard with adverse impacts on air quality, climate, and the public health. Accurate determination of flare locations and estimation of associated emissions are therefore of prime importance. Recently developed Visible Infrared Imaging Radiometer Suite (VIIRS) Nightfire product (VNF) has shown remarkable efficiency in detecting gas flares globally, owing primarily to its use of Shortwave Infrared (SWIR) band in its detection algorithm. This study compares and contrast nocturnal hot source detection by VNF to …

Application Of The Optimal Estimation Method (Oem) To Retrieve Relative Humidity From Raman Lidar Backscatter Measurements., Shayamila N. Mahagammulla Gamage, Robert Sica, Alexander Haefele

Western Research Forum

Accurate measurements of relative humidity (RH) vertical profiles in the atmosphere is important for understanding the earth's weather and the climate system. RH represent the current state of the water vapor in the atmosphere with respect to the ambient air related to saturation. Even minor changes of the RH in the lower atmosphere has a large impact of the global circulation and cloud formation. Due to its high variability RH measurements in the lower atmosphere is significantly challenging. Raman lidar is one of the potential tools that can provide vertical profiles of RH. Typically, temperature and water vapor mixing ratios …

Integrated Raman Lidar And Microwave Radiometer Retrieval Of Atmospheric Water Vapor, Jeffrey Vankerkhove, Robert Sica, Alexander Haefele

Western Research Forum

Water vapor plays a critically important role in many atmospheric processes. However, it is poorly characterized throughout much of the atmosphere, particularly in the UTLS (Upper Troposphere Lower Stratosphere) region, due to lack of accurate measurements. Raman lidar boasts the capacity for excellent spatial and temporal resolution, but requires an external calibration. Microwave radiometers can be calibrated in absolute terms, but have poor height resolution. In this study, we introduce an integrated water vapor retrieval using an optimal estimation method, where the measurements from the Raman Lidar for Meteorological Observation (RALMO) and a RPG-HATPRO radiometer, both located at the MeteoSwiss …

Odu Study Puts The Estimated Price Tag Of A Major Hurricane In Hampton Roads At $40 Billion Or More, News @ Odu

News Items

No abstract provided.

Science Pubs Will Focus On Climate Related Resilience And Communication, Amy Matzke-Fawcett

News Items

No abstract provided.

Asian Long-Range Transport In Relation To Atmospheric Rivers In Northern California, Catherine Liu, Sen Chiao, Ju-Mee Ryoo

Faculty Publications, Meteorology and Climate Science

The study investigates the effect of aerosol long-range transport on precipitation over Northern California during atmospheric river (AR) events in the 2017 cold season (January–April). ARs in 2017 were one of the strongest to date, and the intense precipitation associated with the ARs resulted in flooding, destruction of property, and contamination of water supplies. The Aerosol Optical Depth (AOD) from Moderate Resolution Imaging Spectroradiometer (MODIS) data shows Asian dust traveling across the Northern Pacific Ocean along with AR events. Aerosol measurements in California, provided by the Interagency Monitoring of Protected Visual Environments (IMPROVE), show that more Asian dust tends to …

Parameterizing Wave‐Driven Vertical Constituent Transport In The Upper Atmosphere, Alan Z. Liu, Chester S. Gardner, Yafang Guo

Publications

Dissipating waves contribute to vertical mixing of the atmosphere, alter molecular and eddy diffusion, and induce chemical transport of reactive species. These processes induce strong vertical transport of atmospheric constituents in regions where wave dissipation is significant. The effective wave diffusivity is proportional to the Stokes drift velocity imparted by the spectrum of vertically propagating waves, which is related to the vertical heat and wave energy fluxes. Because the heat flux cannot be derived from wave parameterization schemes employed in most atmospheric models, wave‐driven constituent transport has not been fully incorporated. However, we show in this paper that wave diffusivity …

Umphlett Qci June 2019, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Soil Moisture Conditions

Delayed/Prevented Planting

Impacts to Cattle

Damage to Infrastructure

Temperature

Precipitation

Power-Law Scaling In The Internal Variability Of Cumulus Cloud Size Distributions Due To Subsampling And Spatial Organization, R. A. J. Neggers, P. J. Griewank, Thijs Heus

Physics Faculty Publications

In this study, the spatial structure of cumulus cloud populations is investigated using three-dimensional snapshots from large-domain LES experiments. The aim is to understand and quantify the internal variability in cloud size distributions due to subsampling effects and spatial organization. A set of idealized shallow cumulus cases is selected with varying degrees of spatial organization, including a slowly organizing marine precipitating case and five more quickly organizing diurnal cases over land. A subdomain analysis is applied, yielding cloud number distributions at sample sizes ranging from severely undersampled to nearly complete. A strong power-law scaling is found in the relation between …

Microcontroller Differential Gps To Subtract Signal Delay Due To Ambient Free Electrons In The Ionosphere, Diana Jane Swanson

Physics

The goal of this project is to create a Global Positioning System (GPS) receiver that is more precise than one GPS receiver on its own. The technique is to take the difference between a GPS receiver’s measured position and its actual position, then use radio frequency (RF) communication to send that differential value to another microcontroller GPS receiver. This differential value will be added to the measured second location to get a more accurate position for the second GPS receiver, thus creating a differential GPS.

Tdim Ionospheric Model Tec Maps Of The High-Latitude Northern Hemisphere, Used In The Paper Titled "Hemispherical Shifted Symmetry In Polar Cap F-Region Patch Occurrence: A Survey Of Gps Tec Data From 2015 To 2018", Michael David, Jan J. Sojka

Browse all Datasets

TDIM ionospheric model was run for the year 2018 at 10-day intervals and 2-hr intervals in UT.

Effects Of The Hall Conductivity In Ionospheric Heating Experiments, B. Tulegenov, A. V. Streltsov

Publications

We investigate the role of Hall conductivity in ionospheric heating experiments. Ionosphericheating by powerful X-mode waves changes the Hall and Pedersen conductances in theEandDregions,which lead to the generation of ultra-low frequency (ULF)/extremely-low frequency/very low frequencywaves, when the electric field exists in the ionosphere. The importance of the Hall currents in themagnetosphere-ionosphere interactions, carried by ULF waves and field-aligned currents, has beenconsistently overlooked in studies devoted tothe active experiments. Simulations of the three-dimensionaltwo-fluid magnetohydrodynamic (MHD) model, presented in this paper, demonstrate that the Hallconductivity changes (1) the growth rate and the amplitude of ULF waves generated by the heating and (2)the …