Physical Sciences and Mathematics Commons^™

Atmospheric Circulation And Cyclone Frequency Variations Linked To The Primary Modes Of Greenland Snow Accumulation, Jeffrey C. Rogers, Deborah J. Bathke, Ellen Mosley-Thompson, Sheng-Hung Wang

School of Natural Resources: Faculty Publications

Data from 34 Greenland firn cores, extending from 1982 to 1996, are used to identify spatial accumulation variability patterns and their associated atmospheric circulation and cyclone frequencies. The first principal component, representing west-central Greenland accumulation, is correlated to NAO variability, having increased southwesterly (northeasterly) flow over that area during high (low) accumulation winters. The flow is linked to a relative increase in cyclone activity on the west central region of the ice sheet during high accumulation periods. The second principal component represents accumulation over southeastern Greenland where strong westerly flow leads to high accumulation and an increase in lee cyclones …

On The Uscrn Temperature System, Kenneth Hubbard, X. Lin, C.B. Baker

School of Natural Resources: Faculty Publications

In 2004 a new aspirated surface air temperature system was officially deployed nationally in the U.S. Climate Reference Network (USCRN) commissioned by the National Oceanic and Atmospheric Admin- istration. The primary goal of the USCRN is to provide future long-term and high-quality homogeneous observations of surface air temperature and precipitation that can be coupled to past long-term observations for the detection and attribution of present and future climate change. In this paper two precision air temperature systems are included for evaluating the new USCRN air temperature system based on a 1-yr side-by-side field comparison. The measurement errors of the USCRN …

Efficacy Of Offshore Breakwater Structures In A Eutrophic Midwestern Reservoir, Larry D. Pape

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

No abstract provided.

Mesopredator Movement, Abundance, And Habitat Selection In The Rainwater Basins Of Nebraska, Christina J. Kocer

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

No abstract provided.

Air Temperature Comparison Between The Mmts And The Uscrn Temperature Systems, K. G. Hubbard, X. Lin

School of Natural Resources: Faculty Publications

A new U.S. Climate Reference Network (USCRN) was officially and nationally commissioned by the Department of Commerce and the National Oceanic and Atmospheric Administration in 2004. During a 1-yr side-by-side field comparison of USCRN temperatures and temperatures measured by a maximum-minimum temperature system (MMTS), analyses of hourly data show that the MMTS temperature performed with biases: 1) a systematic bias–ambient-temperature-dependent bias and 2) an ambient-solar-radiation- and ambient-wind- speed-dependent bias. Magnitudes of these two biases ranged from a few tenths of a degree to over 1􏰈C compared to the USCRN temperatures. The hourly average temperatures for the USCRN were the dependent …

Structures And Dynamics Of Quasi-2d Mesoscale Convective Systems, Matthew D. Parker, Richard H. Johnson

School of Natural Resources: Faculty Publications

Recently, three distinct archetypes for midlatitude linear mesoscale convective systems (MCSs) have been identified. This article focuses on the fundamentals of two of these archetypes: convective lines with trailing stratiform (TS) precipitation and convective lines with leading stratiform (LS) precipitation. Both the TS and LS modes typically exhibit quasi-2D reflectivity patterns and quasi-2D environmental storm-relative wind fields. Ongoing work has revealed that there are three common flow structures for these quasi-2D MCSs: front-fed TS systems (which are sustained by front-to-rear storm-relative inflow), as well as front-fed LS and rear-fed LS systems (which are sustained by rear-to-front storm-relative inflow). This paper …

A Self-Calibrating Palmer Drought Severity Index, Nathan Wells, Steve Goddard, Michael Hayes

School of Natural Resources: Faculty Publications

The Palmer Drought Severity Index (PDSI) has been used for more than 30 years to quantify the long-term drought conditions for a given location and time. However, a common critique of the PDSI is that the behavior of the index at various locations is inconsistent, making spatial comparisons of PDSI values difficult, if not meaningless.

A self-calibrating Palmer Drought Severity Index (SC-PDSI) is presented and evaluated. The SC-PDSI automatically calibrates the behavior of the index at any location by replacing empirical constants in the index computation with dynamically calculated values. An evaluation of the SC-PDSI at 761 sites within Nebraska, …

Notes And Correspondence Uncertainties Of Derived Dewpoint Temperature And Relative Humidity, X. Lin, Kenneth Hubbard

School of Natural Resources: Faculty Publications

This paper presents an evaluation of derived dewpoint temperature and derived relative humidity, in which the dewpoint temperature is calculated using measured ambient air temperature and measured relative humidity variables and the derived relative humidity is calculated from measured dewpoint temperature. The derived dewpoint temperature and relative humidity are calculated using algorithms provided by the World Meteorological Organization. The method of uncertainty analysis, provided by the National Institute of Standards and Technology, is applied to calculate the uncertainties of an indirect measurement of derived dewpoint temperature and derived relative humidity. The results from the uncertainty analyses of derived and observed …

Sensor And Electronic Biases/Errors In Air Temperature Measurements In Common Weather Station Networks*, X. Lin, Kenneth Hubbard

School of Natural Resources: Faculty Publications

The biases of four commonly used air temperature sensors are examined and detailed. Each temperature transducer consists of three components: temperature sensing elements, signal conditioning circuitry, and corresponding analog-to-digital conversion devices or dataloggers. An error analysis of these components was performed to determine the major sources of error in common climate networks. It was found that, regardless of microclimate effects, sensor and electronic errors in air temperature measurements can be larger than those given in the sensor manufacturer’s specifications. The root-sum-of-squares (RSS) error for the HMP35C sensor with CR10X datalogger was above 0.2􏰆C, and rapidly increases for both lower (􏰋􏰂20􏰆C) …

Variations In The Teleconnection Of Enso And Summer Rainfall In Northern China: A Role Of The Indian Summer Monsoon*, Song Feng, Qi Hu

School of Natural Resources: Faculty Publications

Observational studies have created a dilemma on how El Nin ̃o–Southern Oscillation (ENSO) may have affected interannual variations of summer rainfall in northern China; some suggested a consistent effect while others showed a complete lack of effect. This dilemma is resolved in this study, which shows that ENSO has affected the summer rainfall in northern China and the effect has varied at multidecadal scales. The question of how the ENSO teleconnection with northern China rainfall variation was established is addressed, and an answer pointing to the Indian summer monsoon as a ‘‘facilitator’’ connecting ENSO and northern China rainfall variation is …

Late Albian Dinosaur Tracks From The Cratonic (Eastern) Margin Of The Western Interior Seaway, Nebraska, Usa, R. M. Joeckel, J. M. Cunningham, R. G. Corner, P. L. Phillips, G. A. Ludvigson

School of Natural Resources: Faculty Publications

No abstract provided.

Accounting For Stream-Aquifer Interactions In The State-Space Discretization Of The Kmn-Cascade For Streamflow Forecasting, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

Achieving Bat Conservation Through Tourism, Lisa A. Pennisi, Stephen M. Holland, Taylor V. Stein

School of Natural Resources: Faculty Publications

No abstract provided.

Using Visitors Motivations To Provide Learning Opportunities At Water-Based Recreation Areas, Taylor V. Stein, Christine B. Denny, Lisa A. Pennisi

School of Natural Resources: Faculty Publications

No abstract provided.

Heuristic Continuous Base Flow Separation, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

Empirical Measurement Of Parasite Transmission Between Groups In A Colonial Bird, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

While epidemiological models have suggested that the spread of parasites
and infectious diseases often depends critically on the extent of movement by infected
individuals between populations, there is little empirical information for any organism on
the frequency of between-group parasite transmission or how it varies spatially. The transmission
of parasites between discrete social groups or populations may also help determine
a host’s total parasite or pathogen exposure. We measured the introduction of parasitic bugs
(Oeciacus vicarius) into colonies of Cliff Swallows (Petrochelidon pyrrhonota) by transient
birds from outside each group. The transmission of bugs increased strongly …

Application Of Snowfall And Wind Statistics To Snow Transport Modeling For Snowdrift Control In Minnesota, Martha Shulski, Mark W. Seeley

School of Natural Resources: Faculty Publications

Models were utilized to determine the snow accumulation season (SAS) and to quantify windblown snow for the purpose of snowdrift control for locations in Minnesota. The models require mean monthly temperature, snowfall, density of snow, and wind frequency distribution statistics. Temperature and precipitation data were obtained from local cooperative observing sites, and wind data came from Automated Surface Observing System (ASOS)/Automated Weather Observing System (AWOS) sites in the region. The temperature-based algorithm used to define the SAS reveals a geographic variability in the starting and ending dates of the season, which is determined by latitude and elevation. Mean seasonal snowfall …

Fire In Southern Appalachians: Fuels, Stand Structure And Oaks, David L. Loftis, Mary A. Arthur, Rex Mann, Jeffrey Lewis

JFSP Research Project Reports

Managers responsible for maintaining the diversity and productivity of Southern Appalachian forests are increasingly turning to prescribed fire as an important management tool in oak dominated forests. The decision to use fire with increasing frequency and spatial extent is based, in part, on an emerging sense of the prehistoric significance of fire in this landscape and its potential to control the proliferation of fire-sensitive competitors in contemporary forests. While it is well documented that fire has been an important ecological force in Southern Appalachian forests for a very long time, there has been little research to demonstrate that prescribed fire …

An Analysis Of Simulated Long-Term Soil Moisture Data For Three Land Uses Under Contrasting Hydroclimatic Conditions In The Northern Great Plains, Rezaul Mamood, Kenneth G. Hubbard

HPRCC Personnel Publications

Soil moisture (SM) plays an important role in land surface and atmosphere interactions. It modifies energy balance near the surface and the rate of water cycling between land and atmosphere. The lack of observed SM data prohibits understanding of SM variations at climate scales under varying land uses. However, with simulation models it is possible to develop a long-term SM dataset and study these issues. In this paper a water balance model is used to provide a quantitative assessment of SM climatologies for three land uses, namely, irrigated corn, rain-fed corn, and grass, grown under three hydroclimatic regimes in Nebraska. …

An Analysis Of Simulated Long-Term Soil Moisture Data For Three Land Uses Under Contrasting Hydroclimatic Conditions In The Northern Great Plains, Rezaul Mahmood, Kenneth Hubbard

School of Natural Resources: Faculty Publications

Soil moisture (SM) plays an important role in land surface and atmosphere interactions. It modifies energy balance near the surface and the rate of water cycling between land and atmosphere. The lack of observed SM data prohibits understanding of SM variations at climate scales under varying land uses. However, with simulation models it is possible to develop a long-term SM dataset and study these issues.

In this paper a water balance model is used to provide a quantitative assessment of SM climatologies for three land uses, namely, irrigated corn, rain-fed corn, and grass, grown under three hydroclimatic regimes in Nebraska. …

Modification Of Growing-Season Surface Temperature Records In The Northern Great Plains Due To Land-Use Transformation: Verification Of Modelling Results And Implication For Global Climate Change, Rezaul Mamood, Kenneth G. Hubbard, Christy Carlson

School of Natural Resources: Faculty Publications

Land-use and land-cover change can modify near-surface atmospheric condition. Mesoscale modelling studies have shown that modification in land use affects near-surface soil moisture storage and energy balance. Such a study in the Great Plains showed that changes in land use from natural grass to irrigated agriculture enhanced soil water storage in the root zone and increased latent energy flux. This increase in latent energy flux would correspond to a decrease in sensible heat flux and, therefore, modify near-surface temperature records. To verify this deduction, we have investigated the changes in the historical near-surface temperature records in Nebraska, USA. We have …

The Role Of Soil Water Availability In Potential Rainfed Rice Productivity In Bangladesh: Applications Of The Ceres-Rice Mode, Rezaul Mahmood, David R. Legates, Mark Meo

School of Natural Resources: Faculty Publications

Soil water stress and its impact on the monsoon season potential rainfed rice productivity in Bangladesh is investigated. A crop growth simulation model, CERES-Rice, is applied to 16 locations representative of the major rice growing regions of Bangladesh to determine the impact of soil water stress on the regional scale potential yield for four transplanting dates: 1 June, 1 July, 15 July, and 15 August. A quantified estimate of potential yield loss for four regions and for Bangladesh as a whole is calculated for water stress during flowering and maturing stages. For example, in Bangladesh, average potential yield for 1 …