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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Drought Analyses Of The Horn´E PoˇZitavie Region (Slovakia) In The Period 1966–2013, Jaroslav Vido, Paulina Nalevankova, Jan Valach, Zbysek Sustek, Tsegaye Tadesse Jul 2019

Drought Analyses Of The Horn´E PoˇZitavie Region (Slovakia) In The Period 1966–2013, Jaroslav Vido, Paulina Nalevankova, Jan Valach, Zbysek Sustek, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

+is study focuses on the characterization of historical drought occurrences in the Horn´e Poˇzitavie region of Slovakia over the period 1966–2013 using Standardized Precipitation-Evapotranspiration Index (SPEI). Trend analyses were evaluated by the Mann–Kendall (MK) test as well as cumulative sum of rank difference (CRD) test. +e results showed that drought occurs in the region regularly (recurrent climate feature), while the trend analysis indicated the trend toward more arid climatic conditions. However, CRD trend analyses showed that the subtrend changed direction toward less drier conditions in the late 1980s and early 1990s. Analyses of SPEI trends in individual months showed a …


Sediment Monitoring To Support Modeling A Reservoir Sediment Flush On A Sand-Bed River In Northern Nebraska, Nathaniel J. Schaepe, Paul M. Boyd Jul 2019

Sediment Monitoring To Support Modeling A Reservoir Sediment Flush On A Sand-Bed River In Northern Nebraska, Nathaniel J. Schaepe, Paul M. Boyd

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS) in cooperation with the United States Army Corps of Engineers (USACE), monitored a sediment flush event from Spencer Dam located on the Niobrara River near Spencer, Nebraska, during the fall of 2014. Data collected during the flush was used to validate a one-dimensional sediment transport model developed by the USACE. The USACE surveyed 26 cross sections within the reservoir and as far as 1 kilometer (km) upstream from the reservoir pool to about 10 km downstream from the dam before and after the flushing event to measure erosion and deposition. They also collected surficial …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2019, Natalie Umphlett, Rezaul Mamood, Paul Flanagan, Emily Brown, Gannon Rush, Crystal J. Stiles Jul 2019

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2019, Natalie Umphlett, Rezaul Mamood, Paul Flanagan, Emily Brown, Gannon Rush, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the director........................................1

Staff spotlight...........................1

Spirit Lake workshop..............2

Product highlight....................3

Outreach events......................3

Research highlight..................4

Update on regional climate conditions..................................4

Northern Plains drought assessment................................5

Recent and upcoming travel and activities.............................6


Droughtscape, Fall 2019, Cory Matteson Jul 2019

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 Jul 2019

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


The Effects Of Economic Factors And Groundwater Policies On The Timing Of Well Drilling, Qianyu Zhang Jul 2019

The Effects Of Economic Factors And Groundwater Policies On The Timing Of Well Drilling, Qianyu Zhang

Department of Agricultural Economics: Dissertations, Theses, and Student Research

Understanding the factors that affect farmers’ irrigation decisions is critical for a better groundwater management. This study addresses the question of how economic, agronomic, and policy variables affect the timing of irrigation adoption in Nebraska. The key contribution of this paper is to identify farmers’ strategic responses to a particular type of policy intervention, a moratorium on well drilling. Our results estimate how farmers respond when a moratorium is announced but not enforced yet, and when neighboring areas implement a moratorium, which we refer as pre-regulation effect and policy spillover effect, respectively. Results show that farmers are more likely to …


Major And Trace Element Analyses For Studying Oceanic Crustal Construction And Ridge Morphology Along The Kane–Atlantis Supersegment Of The Mid-Atlantic Ridge, Yitong Lyu Jul 2019

Major And Trace Element Analyses For Studying Oceanic Crustal Construction And Ridge Morphology Along The Kane–Atlantis Supersegment Of The Mid-Atlantic Ridge, Yitong Lyu

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

Faulting style along slow-spreading ridge segments exerts a major control over oceanic crustal construction and ridge morphology. Seafloor spreading along slow-spreading ridges is classified into asymmetrical detachment faulting and symmetrical spreading styles. Magma supply variations may influence the formation of symmetric versus asymmetric segments, but the factors that derive such variations remain unclear. We present U and Th concentration data by isotope dilution for basalts from 24 to 30 oN MAR, of which 18 samples were retrieved from detachment faulted and 10 from symmetrical segments. The U-Th concentration results from this study are further compiled with prior published data …


Evaluation Of Viirs Nightfire Product And Comparison With Modis And Viirs Active Fire Products In A Russian Gas Flaring Region, Ambrish Sharma Jul 2019

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 …


Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang Jul 2019

Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang

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

This research derives z-score monthly groundwater storage (GWS) anomalies and z-score monthly root zone soil moisture (RZSM) anomalies from products of Gravity Recovery and Climate Experiment Data Assimilation (GRACE-DA). Z-score monthly GWS and RZSM anomalies are compared to two drought indicators: Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI) to investigate the usefulness of GRACE-DA information to detect drought conditions at tree-ring sites. This study also compares z-score monthly GWS and RZSM anomalies with the Tree Ring Standardized Growth Index (TRSGI) that is resampled by bootstrapping to investigate the capability of monitoring forest drought stress. Finally, this research uses …


Groundwater Movement And Interaction With Surface Water Near The Confluence Of The Platte And Elkhorn Rivers, Nebraska, 2016–18, Christopher M. Hobza, Mason J. Johnson, Paul W. Woodward, Kellan R. Strauch, Aaron R. Schepers Jun 2019

Groundwater Movement And Interaction With Surface Water Near The Confluence Of The Platte And Elkhorn Rivers, Nebraska, 2016–18, Christopher M. Hobza, Mason J. Johnson, Paul W. Woodward, Kellan R. Strauch, Aaron R. Schepers

United States Geological Survey: Water Reports and Publications

Document abstract

The State of Nebraska requires a sustainable balance between long-term water supplies and uses of groundwater and surface water and requires Natural Resources Districts to include the effect of groundwater use on surface-water systems as part of their respective integrated management plans. Recent droughts in Nebraska (2000–6; 2012–13) have amplified concerns about the long-term sustainability of groundwater and surface-water resources in the state, and concerns about the effect of groundwater irrigation on both streamflow and the water supplies needed to meet wildlife, recreational, and municipal needs. The lower Platte River provides nearly 100 percent of drinking-water supplies to …


The Antiquity Of The Sahara Desert: New Evidence From The Mineralogy And Geochemistry Of Pliocene Paleosols On The Canary Islands, Spain, Daniel R. Muhs, Joaquín Meco, James R. Budahn, Gary L. Skipp, Juan F. Betancort, Alejandro Lomoschitz Jun 2019

The Antiquity Of The Sahara Desert: New Evidence From The Mineralogy And Geochemistry Of Pliocene Paleosols On The Canary Islands, Spain, Daniel R. Muhs, Joaquín Meco, James R. Budahn, Gary L. Skipp, Juan F. Betancort, Alejandro Lomoschitz

United States Geological Survey: Staff Publications

The Sahara is the largest warm desert in the world, but its age has been controversial, with estimates ranging from Miocene to Holocene. Mineralogical and geochemical data show that paleosols of Pliocene to mid- Pleistocene age on Fuerteventura and Gran Canaria in the Canary Islands have developed in part from inputs of dust from Africa. These paleosols contain quartz and mica, minerals that are abundant in African dust but are rare in the basaltic rocks that dominate the Canary Islands. Trace elements with minimal mobility, Sc, Cr, Hf, Th, and Ta as well as the rare earth elements, show that …


Umphlett Qci June 2019, Natalie Umphlett Jun 2019

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


An Analysis Of Differential Reflectivity Arc Characteristics In 109 Supercell Storms, Matthew Wilson Jun 2019

An Analysis Of Differential Reflectivity Arc Characteristics In 109 Supercell Storms, Matthew Wilson

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

Differential reflectivity (ZDR)arcs are one of the most prominent dual-polarization features of supercell storms, and are manifest as an arc-shaped area of high ZDR along a supercell’s forward flank reflectivity gradient. Since previous modelling studies have hypothesized that the magnitude of the drop-size sorting by the storm-relative wind which creates the arc signature is related to the strength of the low-level shear and SRH in a storm’s environment, the presence of a strong ZDR arc is often said to indicate that a storm may have the potential to develop strong low-level rotation and potentially become tornadic. …


Growth, Condition, And Trophic Relations Of Stocked Trout In Southern Appalachian Mountain Streams, Jesse R. Fischer, Thomas J. Kwak, H. Jared Flowers, W. Gregory Cope, Jacob M. Rash, Douglas A. Besler Apr 2019

Growth, Condition, And Trophic Relations Of Stocked Trout In Southern Appalachian Mountain Streams, Jesse R. Fischer, Thomas J. Kwak, H. Jared Flowers, W. Gregory Cope, Jacob M. Rash, Douglas A. Besler

United States Geological Survey: Staff Publications

Stream trout fisheries are among the most popular and valuable in the United States, but many are dependent on hatcheries to sustain fishing and harvest. Thus, understanding the ecology of hatchery‐reared trout stocked in natural environments is fundamental to management. We evaluated the growth, condition, and trophic relations of Brook Trout Salvelinus fontinalis, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss that were stocked in southern Appalachian Mountain streams in western North Carolina. Stocked and wild (naturalized) trout were sampled over time (monthly; September 2012–June 2013) to compare condition and diet composition and to evaluate temporal dynamics of trophic …


Notes And Discussion Piece: Status Of The Topeka Shiner In Iowa, Clay L. Pierce, Nicholas T. Simpson, Alexander P. Bybel, Courtney L. Zambory, Michael J. Weber, Kevin J. Roe Apr 2019

Notes And Discussion Piece: Status Of The Topeka Shiner In Iowa, Clay L. Pierce, Nicholas T. Simpson, Alexander P. Bybel, Courtney L. Zambory, Michael J. Weber, Kevin J. Roe

United States Geological Survey: Staff Publications

The Topeka shiner Notropis topeka is native to Iowa, Kansas, Minnesota, Missouri, Nebraska, and South Dakota and has been federally listed as endangered since 1998. Our goals were to determine the present distribution and qualitative status of Topeka shiners throughout its current range in Iowa and characterize the extent of decline in relation to its historic distribution. We compared the current (2016–2017) distribution to distributions portrayed in three earlier time periods. In 2016–2017 Topeka shiners were found in 12 of 20 HUC10 watersheds where they occurred historically. Their status was classified as stable in 21% of the HUC10 watersheds, possibly …


Establishing Relationships Between Drought Indices And Wildfire Danger Outputs: A Test Case For The California-Nevada Drought Early Warning System, Daniel J. Mcevoy, Mike Hobbins, Timothy J. Brown, Kristin Vander Molen, Tamara Wall, Justin L. Huntington, Mark D. Svoboda Apr 2019

Establishing Relationships Between Drought Indices And Wildfire Danger Outputs: A Test Case For The California-Nevada Drought Early Warning System, Daniel J. Mcevoy, Mike Hobbins, Timothy J. Brown, Kristin Vander Molen, Tamara Wall, Justin L. Huntington, Mark D. Svoboda

National Drought Mitigation Center: Faculty Publications

Relationships between drought indices and fire danger outputs are examined to (1) incorporate fire risk information into the National Integrated Drought Information System California–Nevada Drought EarlyWarning System and (2) provide a baseline analysis for application of drought indices into a fire risk management framework. We analyzed four drought indices that incorporate precipitation and evaporative demand (E0) and three fire indices that reflect fuel moisture and potential fire intensity. Seasonally averaged fire danger outputs were most strongly correlated to multi-scalar drought indices that use E0 (the Evaporative Demand Drought Index (EDDI) and the Standardized Precipitation Evapotranspiration Index (SPEI)) at approximately annual …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- April 2019, Natalie Umphlett, Rezaul Mamood, Warren Pettee, Paul Flanagan, Bill Sorensen, Jamie Lahowetz, Emily Brown, Crystal J. Stiles Apr 2019

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- April 2019, Natalie Umphlett, Rezaul Mamood, Warren Pettee, Paul Flanagan, Bill Sorensen, Jamie Lahowetz, Emily Brown, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the director........................................1

Staff spotlight...........................1

Climate4Cities.......................2-3

Product highlight....................4

Update on regional climate conditions..................................4

THREDDS workshop...............5

AASC webinar...........................5

Recent and upcoming travel and activities.............................6


Droughtscape, Spring 2019, Cory Matteson Apr 2019

Droughtscape, Spring 2019, Cory Matteson

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

Contents

From the Director

Wet and cool conditions bring drought relief to the West

Notable numbers from Q1

Drought impact summary, 1st quarter 2019

New research examines drought effects on state recreation areas

At Ethiopian space science workshop, NDMC climatologist sees promise in preparing for drought

U.S.- affiliated Pacific Islands now part of U.S. Drought Monitor

Water conservation tips for drought, flood and other disasters

Upcoming events


Examining The Capacity Of Nebraska Rangelands For Cattle Production And Evaluating Drought Management Strategies, Kaitlyn L. Cumming Apr 2019

Examining The Capacity Of Nebraska Rangelands For Cattle Production And Evaluating Drought Management Strategies, Kaitlyn L. Cumming

Department of Agricultural Economics: Dissertations, Theses, and Student Research

This thesis has two chapters focusing on the grazing capacity of Nebraska rangelands, and drought management strategies. The first chapter conducts a gap analysis comparing forage supplied by perennial grasslands to the animal unit months (AUMs) required by the cattle. The purpose of this research was to quantify potential AUM supply (i.e., carrying capacity) of grazing lands dominated by perennial grasses on a regional basis in Nebraska to the AUM demand based on cattle inventories and standard production practices in each region of Nebraska. The results suggest that Nebraska is operating at 100% of potential carrying capacity. Harvest efficiency for …


A Case Study Analysis Of Two Heavy Snowfall Events And Road Weather Implications In 2018 For Nebraska, Nancy Barnhardt Apr 2019

A Case Study Analysis Of Two Heavy Snowfall Events And Road Weather Implications In 2018 For Nebraska, Nancy Barnhardt

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

Weather-related car accidents make up approximately a quarter of all crashes even though the amount of time during the year in which they can occur is minimal in comparison to fair weather day crashes. Maintenance Decision Support Systems (MDSS) were developed to help mitigate the number of crashes that occur during winter weather through improved operations along with reducing chemical usage. An MDSS uses weather information to recommend road treatments based on current and future weather conditions. To evaluate the limitations and capabilities of the Nebraska Department of Transportation Maintenance Decision Support System (NDOT-MDSS), case study analysis was performed on …


Flow Alteration-Ecology Relationships In Ozark Highland Streams: Consequences For Fish, Crayfish And Macroinvertebrate Assemblages, Dustin Thomas Lynch, Douglas R. Leasure, Daniel D. Magoulick Mar 2019

Flow Alteration-Ecology Relationships In Ozark Highland Streams: Consequences For Fish, Crayfish And Macroinvertebrate Assemblages, Dustin Thomas Lynch, Douglas R. Leasure, Daniel D. Magoulick

United States Geological Survey: Staff Publications

We examined flowalteration-ecology relationships in benthic macroinvertebrate, fish, and crayfish assemblages in Ozark Highland streams, USA, over two years with contrasting environmental conditions, a drought year (2012) and a flood year (2013). We hypothesized that: 1) there would be temporal variation in flow alteration-ecology relationships between the two years, 2) flow alteration-ecology relationshipswould be stronger during the drought year vs the flood year, and 3) fish assemblages would show the strongest relationships with flow alteration. We used a quantitative richest-targeted habitat (RTH) method and a qualitative multihabitat (QMH) method to collect macroinvertebrates at 16 USGS gaged sites during both years. …


Flow Alteration-Ecology Relationships In Ozark Highland Streams: Consequences For Fish, Crayfish And Macroinvertebrate Assemblages, Dustin T. Lynch, Douglas R. Easure, Daniel D. Magoulick Mar 2019

Flow Alteration-Ecology Relationships In Ozark Highland Streams: Consequences For Fish, Crayfish And Macroinvertebrate Assemblages, Dustin T. Lynch, Douglas R. Easure, Daniel D. Magoulick

United States Geological Survey: Staff Publications

We examined flowalteration-ecology relationships in benthic macroinvertebrate, fish, and crayfish assemblages in Ozark Highland streams, USA, over two years with contrasting environmental conditions, a drought year (2012) and a flood year (2013). We hypothesized that: 1) there would be temporal variation in flow alteration-ecology relationships between the two years, 2) flow alteration-ecology relationshipswould be stronger during the drought year vs the flood year, and 3) fish assemblages would show the strongest relationships with flow alteration. We used a quantitative richest-targeted habitat (RTH) method and a qualitative multihabitat (QMH) method to collect macroinvertebrates at 16 USGS gaged sites during both years. …


Flood-Inundation Maps Of The Meramec River From Eureka To Arnold, Missouri, 2018, Benjamin J. Dietsch, Kellan R. Strauch Mar 2019

Flood-Inundation Maps Of The Meramec River From Eureka To Arnold, Missouri, 2018, Benjamin J. Dietsch, Kellan R. Strauch

United States Geological Survey: Water Reports and Publications

Document abstract

Libraries of digital flood-inundation maps that spanned a combined 37.2-mile reach of the Meramec River that extended upstream from Eureka, Missouri, to downstream near the confluence of the Meramec and Mississippi Rivers were created by the U.S. Geological Survey (USGS) in cooperation with the United States Army Corps of Engineers, Metropolitan St. Louis Sewer District, Missouri Department of Transportation, Missouri American Water, Federal Emergency Management Agency Region 7, and the cities of Pacific, Eureka, Wildwood, and Arnold. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at https://water.usgs.gov/osw/flood_inundation/, depict estimates of …


Earth Observation And Climate Services For Food Security And Agricultural Decision Making In South And Southeast Asia, Faisal M. Qamer, Tsegaue Tadesse, Mir Matin, Walter L. Ellenburg, Benjamin Zaitchik Mar 2019

Earth Observation And Climate Services For Food Security And Agricultural Decision Making In South And Southeast Asia, Faisal M. Qamer, Tsegaue Tadesse, Mir Matin, Walter L. Ellenburg, Benjamin Zaitchik

National Drought Mitigation Center: Faculty Publications

Deliberations on new developments in the use of Earth observation for agriculture and food security in South and Southeast Asia gathered 120 participants to discuss i) agricultural and hydrological drought monitoring and early warning systems, ii) crop mapping and yield estimation, and iii) risk financing and agrometeorological advisory services.


Umphlett Qci March 2019, Natalie Umphlett Mar 2019

Umphlett Qci March 2019, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature Anomalies

Plains Snowpack

Agriculture

Energy

Transportation

Temperature

Precipitation


Newgeochemical Evidence For The Origin Of North America's Largest Dune Field, The Nebraska Sand Hills, Central Great Plains, Usa, Daniel R. Muhs, James R. Budahn Feb 2019

Newgeochemical Evidence For The Origin Of North America's Largest Dune Field, The Nebraska Sand Hills, Central Great Plains, Usa, Daniel R. Muhs, James R. Budahn

United States Geological Survey: Staff Publications

The Nebraska SandHills region is the largest dune field inNorthAmerica and has diverse aeolian landforms. It has been active during both the late Pleistocene and late Holocene. Despite decades of study, the source of sediment for this large sand sea is still controversial. Here we report new trace element compositions of aeolian sand that are compared to four hypothesized sediment sources, Tertiary rocks of the Arikaree Group and Ogallala Group, unconsolidated sands of Pliocene age, and Platte River systemsands. All four potential sources have amineralogy that is similar to the Nebraska Sand Hills. K/Rb, K/Ba, Sc-Th-La, Eu/Eu*, LaN/YbN, As/Sb, and …


Building A High-Resolution Vegetation Outlook Model To Monitor Agricultural Drought For The Upper Blue Nile Basin, Ethiopia, Yared Bayissa, Tsegaye Tadesse, Getachew B. Demisse Feb 2019

Building A High-Resolution Vegetation Outlook Model To Monitor Agricultural Drought For The Upper Blue Nile Basin, Ethiopia, Yared Bayissa, Tsegaye Tadesse, Getachew B. Demisse

National Drought Mitigation Center: Faculty Publications

To reduce the impacts of drought, developing an integrated drought monitoring tool and early warning system is crucial and more effective than the crisis management approach that is commonly used in developing countries like Ethiopia. The overarching goal of this study was to develop a higher-spatial-resolution vegetation outlook (VegOut-UBN) model that integrates multiple satellite, climatic, and biophysical input variables for the Upper Blue Nile (UBN) basin. VegOut-UBN uses current and historical observations in predicting the vegetation condition at multiple leading time steps of 1, 3, 6, and 9 dekades. VegOut-UBN was developed to predict the vegetation condition during the main …


Incorporating Uh Occurrence Time To Ensemble-Derived Tornado Probabilities, Burkely T. Gallo, Adam J. Clark, Bryan T. Smith, Richard L. Thompson, Israel Jirak, Scott R. Dembek Feb 2019

Incorporating Uh Occurrence Time To Ensemble-Derived Tornado Probabilities, Burkely T. Gallo, Adam J. Clark, Bryan T. Smith, Richard L. Thompson, Israel Jirak, Scott R. Dembek

United States Department of Commerce: Staff Publications

Probabilistic ensemble-derived tornado forecasts generated from convection-allowing models often use hourly maximum updraft helicity (UH) alone or in combination with environmental parameters as a proxy for right-moving (RM) supercells. However, when UH occurrence is a condition for tornado probability generation, false alarm areas can occur from UH swaths associated with nocturnal mesoscale convective systems, which climatologically produce fewer tornadoes than RM supercells. This study incorporates UH timing information with the forecast near-storm significant tornado parameter (STP) to calibrate the forecast tornado probability. To generate the probabilistic forecasts, three sets of observed climatological tornado frequencies given an RM supercell and STP …


Insights Into Paleoenvironmental Conditions, Relative Sea-Level, And Carbonate Reservoir Quality Using Ichnology: Middle–Upper Miocene Slope Deposits, Great Bahama Bank, Ryan M. Mustacato Feb 2019

Insights Into Paleoenvironmental Conditions, Relative Sea-Level, And Carbonate Reservoir Quality Using Ichnology: Middle–Upper Miocene Slope Deposits, Great Bahama Bank, Ryan M. Mustacato

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

Detailed ichnological and petrographic analyses were conducted on two biostratigraphically-constrained intervals (11.9-11.3 Ma and 10.7-9.4 Ma) from the Middle-Upper Miocene stratigraphy of the Great Bahama Bank’s leeward margin to assess spatiotemporal trends in paleoenvironmental conditions and reservoir properties in carbonate slope deposits. Six ichnofacies, varied in expression, are documented: the Skolithos Ichnofacies (distal and impoverished expressions) the Cruziana Ichnofacies (proximal, archetypal, distal and impoverished expressions), the Zoophycos Ichnofacies, the Nereites Ichnofacies, the Glossifungites Ichnofacies, and the Trypanites Ichnofacies. An analysis of spatiotemporal ichnofacies trends reveals two distinct responses of the benthic community to significant environmental perturbations on the slope. An …


Spatial Heterogeneity Of Temporal Shifts In Extreme Precipitation Across India, Manas Khan, Francisco Munoz-Arriola, Rehana Shaik, Penny Greer Jan 2019

Spatial Heterogeneity Of Temporal Shifts In Extreme Precipitation Across India, Manas Khan, Francisco Munoz-Arriola, Rehana Shaik, Penny Greer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

When analyzing trends and patterns of extreme precipitation, one can easily generalize the shifts caused by external climate forcings and map a single temporal shift of annual precipitation. However, the complexity of a changing environment evidences spatially distributed shifts particularly those of extreme precipitation which are essential in planning and designing enterprises and, ultimately, in managing infrastructure across scales. The goal of this study is to characterize the spatial heterogeneity of shifts in the increasing pace of extreme events over India. The study has a two-part hypothesis: (1) the number of grid cells with significant trends in annual precipitation (P), …