Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2002

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 361 - 390 of 3435

Full-Text Articles in Physical Sciences and Mathematics

A New Technology To Repel Birds: The High-Intensity Acoustic Bird Dispersion System (Hiabds), Xi Baoshu, Zhou Mingjun, Wang Jingqun, Richard A. Dolbeer, Thomas W. Seamans Oct 2002

A New Technology To Repel Birds: The High-Intensity Acoustic Bird Dispersion System (Hiabds), Xi Baoshu, Zhou Mingjun, Wang Jingqun, Richard A. Dolbeer, Thomas W. Seamans

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

A High-intensity Acoustic Bird Dispersion System (HIABDS), invented by Professor Xi Baoshu, is a new nonlethal device for dispersing birds from airports and other locations. The device employs a unique electro-pneumatic loudspeaker which can amplify recorded wildlife vocalizations or artificial sounds of varying frequencies to high power levels and project them over long distances. The sound pressure reaches 135 dB at 10-m distance. In China, HIABDS is being used at Lanzhou Airport to disperse upland buzzards (Buteo hemilasius), whose numbers declined by 80% after 1 year of deployment. During 2001-2002, HIABDS was used at Tianjin Binhai International Airport …

Go to article

Strides In Bird Hazard Control At Entebbe International Airport, Gloria Korabo Bitebekezi Oct 2002

Strides In Bird Hazard Control At Entebbe International Airport, Gloria Korabo Bitebekezi

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

The location of Entebbe International Airport within the Entebbe peninsula bird sanctuary would make it one of the most bird-strike prone airports in the world. However the airport actually has a relatively clean strike record. Since 1998, the number of bird strike incidents that caused damage to aircraft has been on the decline. This paper illustrates the methods used at Entebbe International Airport and their effectiveness in controlling different species of birds.

Go to article

Bird Hazard Control Program At Panama Airports, Esteban Godinez Oct 2002

Bird Hazard Control Program At Panama Airports, Esteban Godinez

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

ICAO Bird Information System (IBIS) has been conduced at Panama airports since 1996. Bird strike notifications, technical reports as well as wildlife control procedures have been developing as essential roles of the National Bird Hazard Committee and its Wildlife Limitation Programs. Sixty-four (64) bird strikes with different aircraft were recorded and sent to ICAO so far, while an additional 154 collisions (71%) were not reported to ICAO because of the failure to determine the aircraft involved. Among the birds struck at airports, the most outstanding species are the common barn owl (Tyto alba) and the black vulture (Coragyps …

Go to article

Wildlife Hazard Management In Micronesia: Aviation Safety In Uncharted Territory, Daniel S. Vice Oct 2002

Wildlife Hazard Management In Micronesia: Aviation Safety In Uncharted Territory, Daniel S. Vice

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

The islands of Micronesia support small, but growing, commercial and military aviation routes. A developing tourism industry, coupled with increased demands for military training sites, is bringing aviation traffic to remote and occasionally primitive island settings. While flight volumes are low relative to mainland settings, the nature of aviation in the islands is that of self- sufficiency and minimal infrastructure, which creates difficult flight situations. Pilots flying island routes face numerous challenges, including wildlife hazards that are generally unmitigated. Although major infrastructure and safety improvements have been made across many of the civilian airports in Micronesia, the impact of wildlife …

Go to article

Bird Strikes In Courts: The Genoa Case, Valter Battistoni Oct 2002

Bird Strikes In Courts: The Genoa Case, Valter Battistoni

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

There have not been many court cases, be it criminal or civil, concerning accidents, or even compensation for damages, following bird strikes. Generally, those involved prefer to reach an agreement out of court. The first court sentence in Italy on this subject was pronounced by the Civil Court of Genoa in 2001. The carrier had sued a number of entities (Ministry of Transport, Airport Operator, Air Traffic Control Agency) for damages resulting from a multiple impact between a BAE 146 and a flock of gulls (Larus sp.) that occurred on 7 June 1989 at Genoa Airport. On that occasion …

Go to article

Canada Goose Population Management At The Minneapolis-St. Paul International And Downtown St. Paul Airports, James A. Cooper Oct 2002

Canada Goose Population Management At The Minneapolis-St. Paul International And Downtown St. Paul Airports, James A. Cooper

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

A Canada goose (Branta canadensis) control program was initiated at the Minneapolis-St. Paul International Airport (MSP) in 1984, and at the Downtown St. Paul Airport (STP) in 1994. Flightless geese >16 km from these airports were trapped (MSP 1,734; STP 1,397), neck-banded (MSP 1,047; STP 502), and observed and counted weekly in fall at 22 and 6 locations >5 km from MSP and STP, respectively. Efficacy was also measured by observing fall goose flights through the operations airspace in 1984-1987 and 1998-2001 (MSP), and 1994-2001 (STP). Based on neckband origin of birds observed >2 km from the airfields, …

Go to article

Monte-Carlo Simulation Of Birdstrike To Support Rule Making For Large Birds, Julian M. Reed Oct 2002

Monte-Carlo Simulation Of Birdstrike To Support Rule Making For Large Birds, Julian M. Reed

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

A clear need was established by the aero-engine manufacturers and the certifying authorities for a re-assessment of the published rules governing engine certification for large flocking birds. A task group was set up to address this need at the beginning of 2000. Early in this program, it was determined that a statistical approach to the rule making was required and the Monte-Carlo technique was proposed and accepted. This paper discusses the implementation of the Monte-Carlo technique to simulate bird strike events from the Rolls-Royce viewpoint and describes the various refinements that have been made in order to ensure an adequate …

Go to article

Aircraft Engines And Large Flocking Birds, Richard Parker Oct 2002

Aircraft Engines And Large Flocking Birds, Richard Parker

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

This paper will present a summary of the results of the ARAC (engine) Bird Ingestion Phase II rule making effort. The effort was to evaluate the hazard to transport category aircraft, of large flocking birds, and to revise the engine certification requirements as appropriate. The paper will discuss the revision to engine certification requirements. It will also discuss the recommendation of the task group regarding the importance of continuing effort for bird control at the airport.

Go to article

Potential Of Grass-Endophytes As A Bird Deterrent: Concept Testing With Canada Geese, Chris G. L. Pennell, Phil Rolston Oct 2002

Potential Of Grass-Endophytes As A Bird Deterrent: Concept Testing With Canada Geese, Chris G. L. Pennell, Phil Rolston

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Problems caused by birds in the agricultural, horticultural, recreational and the aviation industries are escalating world wide as man develops environments that are attractive to birds. Chemical repellents, bird scarers, and exclusion netting are being used to keep birds away by taste, fright and containment. Habitat management using grasses with selected endophytes may be a new tool for minimizing bird nuisance problems in these industries. Canada geese (Branta Canadensis) were offered selected ryegrass/endophyte Neotyphodium lolli seed and herbage to examine the effects of known endophyte alkaloids on their feeding behavior in 2000-2001. Forty geese were captured annually, contained …

Go to article

Aspects Of The Feeding Ecology Of Avifauna At An Inland Airport, South Africa, Ordino Kok, Lettie Kok Oct 2002

Aspects Of The Feeding Ecology Of Avifauna At An Inland Airport, South Africa, Ordino Kok, Lettie Kok

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Bloemfontein airport, situated in the central Free State, experiences the greatest number of bird-aircraft collisions at South African airports, relative to its (low) air traffic. In an attempt to rectify the situation, aspects of the feeding ecology of birds presenting a potential hazard at the airport were investigated. Plant surveys indicated that the study area can be classified as a dry Cymbopogon – Themeda veld type in a relatively good condition. Using 270 pitfall traps over a continuous period of 15 months, it was established that more than twice as many ground-living invertebrates, mainly insects, occurred in grass kept permanently …

Go to article

Assessing Bird Strike Hazards In Coastal Wetlands Through Field Experiments, John Ledbetter, John Gray Oct 2002

Assessing Bird Strike Hazards In Coastal Wetlands Through Field Experiments, John Ledbetter, John Gray

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Santa Barbara Municipal Airport (SBA) is located in and adjacent to Goleta Slough, a large coastal salt marsh with limited tidal circulation. Various government and non-government agencies are pursuing a long-term project to restore the historic tidal circulation to the slough to improve ecological conditions. SBA recently completed a study to assess feasibility of conducting a controlled field experiment in the slough to evaluate the relationship between bird strike hazards and the presence of tidal and non-tidal wetlands near the airfield. The study indicated that a limited field experiment, in which new estuarine marsh areas are temporarily restored, would provide …

Go to article

A Paradigm Shift In Bird Strike Prevention By The Israeli Air Force, Nicholas B. Carter, Eyal Cohen Oct 2002

A Paradigm Shift In Bird Strike Prevention By The Israeli Air Force, Nicholas B. Carter, Eyal Cohen

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Over the past 20 years, the Israeli Air Force (IAF) has focused attention in bird strike prevention on collisions between aircraft and migrating birds during low-level flight operations. Only in the last 2 years has the IAF begun to tackle the problem of reducing bird-aircraft collisions at or near airfields. A dramatic shift in thinking has led the IAF to initiate complete wildlife control programs at its airbases, featuring the employment of border collies and wildlife control officers to help eliminate the risk of wildlife collisions within the control zone (CTR) of each airfield. As a crucial component of this …

Go to article

Translocating Common Nighthawks At Mcconnell Air Force Base, Kansas To Reduce Aircraft Strikes, John L. Cummings, Patricia A. Pochop, James E. Davis, Darryl L. York Oct 2002

Translocating Common Nighthawks At Mcconnell Air Force Base, Kansas To Reduce Aircraft Strikes, John L. Cummings, Patricia A. Pochop, James E. Davis, Darryl L. York

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

McConnell Air Force Base (MAFB) experiences a unique bird/aircraft hazard problem with migrating common nighthawks (Chordeiles minor) from August-October. Nighthawks are the most commonly struck species at MAFB, representing about 38% of total reported bird/aircraft strikes and 82% of the strikes from August-October. Factors that contribute to an over abundance of nighthawks on MAFB are: abundant foraging opportunities in close proximity to the airfield, available roosting habitat for nighthawks on and around the airfield, the lack of a Bird Aircraft Strike Hazard program to address nighthawks, and the location of MAFB on a nighthawk migration route. Approaches for …

Go to article

A Small Pond Off-Airfield Provides More Than Water, Nigel Horton Oct 2002

A Small Pond Off-Airfield Provides More Than Water, Nigel Horton

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Land use changes around aerodromes are becoming more problematical as conservation groups increasingly press for eco-friendly restorations, especially of water areas. Often the requirement is to encourage insects or plants or recreational use of such areas. However, these same beneficial features for biodiversity, can enhance the already considerable off-airfield bird attraction. A single case study illustrates the slow, generally unnoticed, development of a small water feature as an attraction to increasing numbers of birds and species over a period of about 10 years. This and a second study reveal how a "must feed the birds" mentality influences local bird populations. …

Go to article

Automated Haze Systems With Methyl Anthranilate Eliminate Nuisance Birds In Aviation Hangars, Warehouses, Airports, Bruce E. Vergote Oct 2002

Automated Haze Systems With Methyl Anthranilate Eliminate Nuisance Birds In Aviation Hangars, Warehouses, Airports, Bruce E. Vergote

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Automated haze systems (The BirdHazer) combined with Methyl Anthranilate (MA) is proven effective and cost efficient as an application method for eliminating nuisance birds in aviation hangars, warehouses, and airport facilities. Proper placement of the BirdHazer system which is based on air flow circulation allows to deliver a clean, dry haze, producing a mean droplet diameter size of 5 microns , which also eliminates the possibility of permeation and any settled residue. Three preliminary test studies were successfully completed at 2 dairy barn locations, and a salt storage warehouse. The fourth testing site was conducted at a maintenance hangar at …

Go to article

Responses Of Captive Birds To Candidate Perching Deterrents On Faa Llwas Units, Michael L. Avery, Ann C. Genchi Oct 2002

Responses Of Captive Birds To Candidate Perching Deterrents On Faa Llwas Units, Michael L. Avery, Ann C. Genchi

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Successful operation of the FAA’s Low-Level Windshear Alert System (LLWAS) depends largely on birds not perching on the wind-sensing units which are installed atop poles 40-45 m tall. Because new LLWAS units will be erected at airports throughout North America, anti- perching devices must deter numerous avian species ranging widely in body size and behavioral pattern. To determine the most promising devices, we conducted pen trials with brown-headed cowbirds, fish crows, barred owls, great horned-owls and black vultures. Birds were given free access to an unmodified sensor unit mounted on a tripod for 24 hours, during which the only alternative …

Go to article

Evaluation Of Electrobraid Fencing As A Deer Barrier, Thomas W. Seamans, Zachary J. Patton, Kurt .. Vercauteren Oct 2002

Evaluation Of Electrobraid Fencing As A Deer Barrier, Thomas W. Seamans, Zachary J. Patton, Kurt .. Vercauteren

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Increasing white-tailed deer (Odocoileus virginianus) populations in North America have lead to direct threats to public safety as well as agricultural losses. Fencing is often used to keep deer from causing damage at both airports and agricultural areas. Tall, chain-link fences have been used successfully but are often prohibitively expensive. Electric fences have potential to offer a less expensive alternative. We tested a new electric fence design marketed under the name ElectroBraid. This fence, comprised of 0.6-cm polyester rope with copper wire woven into it, is carried on frangible, fiberglass posts set at 15-m intervals. From January to …

Go to article

“Birdstrike” – What’S The Word? (Poster), Carla Dove Oct 2002

“Birdstrike” – What’S The Word? (Poster), Carla Dove

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

The word(s) “bird strike”, “bird-strike”, or “birdstrike” has been used inconsistently throughout the literature for as long as birds have been colliding with aircraft. A recent search of peer-reviewed articles in the Zoological Record and Biological Abstracts dating back to 1969 resulted in 52 articles that pertained to bird-aircraft collisions. Of those, 67% used two words (bird strike); 22% used a hyphenated word (bird-strike); 5.5% used one word (birdstrike), and 5.5% actually used both two words and the hyphenated version in the same paper! A brief glance through the proceedings and abstracts of recent Bird Strike Committee Meetings also exemplifies …

Go to article

Birdstrike Identification (Poster), Carla Dove Oct 2002

Birdstrike Identification (Poster), Carla Dove

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Identification of feather evidence retrieved from birdstrikes provides essential information that allows airfield managers, engineers, pilots and government agencies to work together to prevent damaging birdstrikes. Knowing the identity of the birds that are causing problems is the first step in formulating a plan to discourage birds from interfering with aviation safety. The feather identification process is complex and involves cleaning feather material, microscopic examination, and whole feather comparisons with specimens in a museum collection. This poster presents the feather identification technique and provides information to various agencies on how and where to send birdstrike remains for identification.

Go to article

Conducting An Economical Wildlife Hazard Assessment Using A Wildlife Incursion Log (Poster), Elizabeth Rogers, David Tiller Oct 2002

Conducting An Economical Wildlife Hazard Assessment Using A Wildlife Incursion Log (Poster), Elizabeth Rogers, David Tiller

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Small and moderate-sized airports face increasing financial constraints. A need for a wildlife hazard assessment can represent a real financial hardship. We describe how a wildlife incursion log maintained by airport personnel can provide an economical means of assessing wildlife hazards in a rural landscape. Using such a log with records for 208 days, we created a relational database that could be analyzed with simple summary statistics. Using the incursion log, we examined seasonal shifts in average daily incursions (such as increased sandhill cranes in the spring), persistent year- round presence of some species (such as American crow), and the …

Go to article

Environmental Analysis Of Wildlife Hazard Management Programs: Application Of Nepa And Possible Consequences For Implementing New Plans (Poster), Ken Wallace Oct 2002

Environmental Analysis Of Wildlife Hazard Management Programs: Application Of Nepa And Possible Consequences For Implementing New Plans (Poster), Ken Wallace

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

The operating certificate required for airports that accommodate commercial-service air carriers stipulates that the airports be able to conduct safe operations, pursuant to the Federal Aviation Act of 1958. Under Federal Aviation Regulation Part 139, most airports must prepare and implement a wildlife hazard management plan (WHMP) as part of the certification process. Required components of the WHMP include the priorities for needed habitat modification and changes in land use as a result of those modifications. Because habitat modification is often a relatively permanent procedure to reduce wildlife use of airports, it is a preferred method by airport operators for …

Go to article

Successful Use Of Alarm/Alert Call Playback To End Canada Goose Problems At An Ohio Business Park (Poster), Philip C. Whitford Oct 2002

Successful Use Of Alarm/Alert Call Playback To End Canada Goose Problems At An Ohio Business Park (Poster), Philip C. Whitford

2002 Bird Strike Committee-USA/Canada, 4th Annual Meeting, Sacramento, CA

Burgeoning continental resident Canada goose populations have led to increases in aircraft strikes. Once on or near airfields, geese have proven difficult to move and keep away. Playback of naturally recorded alarm and alert calls of the species was coupled with multiple harassment techniques to determine if this strategy would prove effective at removal of long-term resident geese from a 24-ha business park in Dayton, Ohio. The study began 26 February 2002, following territorial establishment by the geese, and continued until the last few geese had abandoned the property as of 14 May 2002. Most geese present were reusing nest …

Go to article

Toward Dynamic Interoperability Of Mobile Agent Systems, Arne Grimstrup, Robert Gray, David Kotz, Maggie Breedy, Marco Carvalho, Thomas Cowin, Daria Chacon, Joyce Barton, Chris Garrett, Martin Hofmann Oct 2002

Toward Dynamic Interoperability Of Mobile Agent Systems, Arne Grimstrup, Robert Gray, David Kotz, Maggie Breedy, Marco Carvalho, Thomas Cowin, Daria Chacon, Joyce Barton, Chris Garrett, Martin Hofmann

Dartmouth Scholarship

Mobile agents are an increasingly popular paradigm and in recent years there has been a proliferation of mobile-agent systems. These systems are, however, largely incompatible with each other. In particular, agents cannot migrate to a host that runs a different mobile-agent system. Prior approaches to interoperability have tried to force agents to use a common API and so far none have succeeded. This goal led to our efforts to develop mechanisms that support dynamic runtime interoperability of mobile-agent systems. This paper describes the \em Grid Mobile-Agent System, which allows agents to migrate to different mobile-agent systems.

Go to article

Molecular Dynamics Simulations Of Sodium Dodecyl Sulfate Micelle In Water: The Behavior Of Water, Chrystal Bruce, Sanjib Senapati, Max Berkowitz, L. Perera, M. Forbes Oct 2002

Molecular Dynamics Simulations Of Sodium Dodecyl Sulfate Micelle In Water: The Behavior Of Water, Chrystal Bruce, Sanjib Senapati, Max Berkowitz, L. Perera, M. Forbes

Chrystal D. Bruce

Using a 5 ns explicit atom molecular dynamics simulation of a 60 monomer sodium dodecyl sulfate micellar system containing 7579 TIP3P water molecules, the behavior of water in different electrostatic environments was examined. Structural evaluation of the system revealed that penetration of water molecules into the micelle was restricted to the headgroup region, leaving a 12 Å water-free hydrocarbon core. Water molecules near the headgroup exhibit a distortion of the water−water hydrogen bonding network due to headgroup oxygen−water hydrogen bond formation. The dynamic implications of this distortion are manifested in the decay of the dipole autocorrelation function, Φ(t) and translational …

Go to article

Rapid Postseismic Transients In Subduction Zones From Continuous Gps, Timothy I. Melbourne, Frank H. Webb, Joann M. Stock, Christoph Reigber Oct 2002

Rapid Postseismic Transients In Subduction Zones From Continuous Gps, Timothy I. Melbourne, Frank H. Webb, Joann M. Stock, Christoph Reigber

All Faculty Scholarship for the College of the Sciences

Continuous GPS time series from three of four recently measured, large subduction earthquakes document triggered rapid postseismic fault creep, representing an additional moment release upward of 25% over the weeks following their main shocks. Data from two Mw = 8.0 and Mw = 8.4 events constrain the postseismic centroids to lie down dip from the lower limit of coseismic faulting, and show that afterslip along the primary coseismic asperities is significantly less important than triggered deep creep. Time series for another Mw = 7.7 event show 30% postseismic energy release, but here we cannot differentiate between afterslip …

Go to article

A Study Of Indoor Carbon Dioxide Levels And Sick Leave Among Office Workers, Theodore A. Myatt, John W. Staudenmayer, Kate Adams, Michael Walters, Stephen N. Rudnick, Donald K. Milton Oct 2002

A Study Of Indoor Carbon Dioxide Levels And Sick Leave Among Office Workers, Theodore A. Myatt, John W. Staudenmayer, Kate Adams, Michael Walters, Stephen N. Rudnick, Donald K. Milton

John W Staudenmayer

Background A previous observational study detected a strong positive relationship between sick leave absences and carbon dioxide (CO2) concentrations in office buildings in the Boston area. The authors speculated that the observed association was due to a causal effect associated with low dilution ventilation, perhaps increased airborne transmission of respiratory infections. This study was undertaken to explore this association. Methods We conducted an intervention study of indoor CO2 levels and sick leave among hourly office workers employed by a large corporation. Outdoor air supply rates were adjusted periodically to increase the range of CO2 concentrations. We recorded indoor CO2 concentrations …

Go to article

Volcanic Mound Fields On The East Pacific Rise, 16˚-19˚S: Low Effusion Rate Eruptions At Overlapping Spreading Centers For The Past 1 Myr, Scott M. White, Ken C. Macdonald, John Sinton Oct 2002

Volcanic Mound Fields On The East Pacific Rise, 16˚-19˚S: Low Effusion Rate Eruptions At Overlapping Spreading Centers For The Past 1 Myr, Scott M. White, Ken C. Macdonald, John Sinton

Faculty Publications

Volcanic mound fields identified on SeaMARC II and HMR1 12 kHz side-scan data from the southern East Pacific Rise (SEPR) occur near overlapping spreading centers (OSCs) and migration traces of OSCs. The volcanic mound fields appear as a distinctive hummocky seafloor fabric due to side-scan backscatter reflections from clusters of moundshaped reflectors. The lack of growth of the mound fields away from the ridge axis, and their occurrence in association with OSC traces, suggests that mound fields form along the ridge crest near OSCs. Volcanic mound fields are found where 120 kHz side-scan and visual observations find fields of pillow …

Go to article

High Frequency Gravity Waves Observed In Oh Airglow At Starfire Optical Range, Nm: Seasonal Variations In Momentum Flux, Jing Tang, Alan Z. Liu, Gary R. Swenson Oct 2002

High Frequency Gravity Waves Observed In Oh Airglow At Starfire Optical Range, Nm: Seasonal Variations In Momentum Flux, Jing Tang, Alan Z. Liu, Gary R. Swenson

Physical Sciences - Daytona Beach

Airglow imager and Na wind/temperature lidar measurements at Starfire Optical Range, New Mexico (35ºN, 107ºW) are used to estimate the seasonal variation of the vertical fluxes of horizontal momentum carried by high frequency Atmospheric Gravity Waves (AGWs). The cross-correlation coefficients between the vertical and horizontal wind perturbations were calculated from the OH airglow imager data collected during 32 nights in 1998, 1999 and 2000. The RMS wind velocities were deduced from the lidar measurements. The combined information was used to estimate the upper limit of the momentum flux. The meridional component of the vertical flux of horizontal momentum was observed …

Go to article

Phase And Amplitude Of Ecosystem Carbon Release And Uptake Potentials As Derived From Fluxnet Measurements, Eva Falge, John Tenhunen, Dennis D. Baldocchi, Marc Aubinet, Peter Bakwin, Paul Berbigier, Christian Bernhofer, Jean-Marc Bonnefond, George Burba, Robert Clement, Kenneth J. Davis, Jan A. Elbers, Matthias Falk, Allen H. Goldstein, Achim Grelle, Andre Granier, Thomas Grunwald, Jon Gundmondsson, David Hollinger, Ivan A. Janssens, Petri Keronen, Andrew S. Kowalski, Gabriel Katul, Beverly E. Law, Yadvinder Malhi, Tilden Meyers, Russell K. Monson, Eddy Moors, J. William Munger, Walt Oechel, Kyawtha Paw U, Kim Pilegaard, Ullar Rannik, Corinna Rebmann, Andrew E. Suyker, Halldor Thorgeirsson, Giampiero Tirone, Andrew Turnipseed, Kell Wilson, Steve Wofsy Oct 2002

Phase And Amplitude Of Ecosystem Carbon Release And Uptake Potentials As Derived From Fluxnet Measurements, Eva Falge, John Tenhunen, Dennis D. Baldocchi, Marc Aubinet, Peter Bakwin, Paul Berbigier, Christian Bernhofer, Jean-Marc Bonnefond, George Burba, Robert Clement, Kenneth J. Davis, Jan A. Elbers, Matthias Falk, Allen H. Goldstein, Achim Grelle, Andre Granier, Thomas Grunwald, Jon Gundmondsson, David Hollinger, Ivan A. Janssens, Petri Keronen, Andrew S. Kowalski, Gabriel Katul, Beverly E. Law, Yadvinder Malhi, Tilden Meyers, Russell K. Monson, Eddy Moors, J. William Munger, Walt Oechel, Kyawtha Paw U, Kim Pilegaard, Ullar Rannik, Corinna Rebmann, Andrew E. Suyker, Halldor Thorgeirsson, Giampiero Tirone, Andrew Turnipseed, Kell Wilson, Steve Wofsy

School of Natural Resources: Faculty Publications

As length and timing of the growing season are major factors explaining differences in carbon exchange of ecosystems, we analyzed seasonal patterns of net ecosystem carbon exchange (FNEE) using eddy covariance data of the FLUXNET data base (http://www-eosdis.ornl.gov/FLUXNET). The study included boreal and temperate, deciduous and coniferous forests, Mediterranean evergreen systems, rainforest, native and managed temperate grasslands, tundra, and C3 and C4 crops. Generalization of seasonal patterns are useful for identifying functional vegetation types for global dynamic vegetation models, as well as for global inversion studies, and can help improve phenological modules in SVAT or biogeochemical models. …

Go to article

Seasonality Of Ecosystem Respiration And Gross Primary Production As Derived From Fluxnet Measurements, Eva Falge, Dennis D. Baldocchi, John Tenhunen, Marc Aubinet, Peter Bakwin, Paul Berbigier, Christian Bernhofer, George Burba, Robert Clement, Kenneth J. Davis, Jan A. Elbers, Allen H. Goldstein, Achim Grelle, Andre Granier, Jon Gundmundsson, David Hollinger, Andrew S. Kowalski, Gabriel Katul, Beverly E. Law, Yadvinder Malhi, Tilden Meyers, Russell K. Monson, J. William Munger, Walt Oechel, Kyaw Tha Paw U, Kim Pilegaard, Ullar Rannik, Corinna Rebmann, Andrew E. Suyker, Riccardo Valentini, Kell Wilson, Steve Wofsy Oct 2002

Seasonality Of Ecosystem Respiration And Gross Primary Production As Derived From Fluxnet Measurements, Eva Falge, Dennis D. Baldocchi, John Tenhunen, Marc Aubinet, Peter Bakwin, Paul Berbigier, Christian Bernhofer, George Burba, Robert Clement, Kenneth J. Davis, Jan A. Elbers, Allen H. Goldstein, Achim Grelle, Andre Granier, Jon Gundmundsson, David Hollinger, Andrew S. Kowalski, Gabriel Katul, Beverly E. Law, Yadvinder Malhi, Tilden Meyers, Russell K. Monson, J. William Munger, Walt Oechel, Kyaw Tha Paw U, Kim Pilegaard, Ullar Rannik, Corinna Rebmann, Andrew E. Suyker, Riccardo Valentini, Kell Wilson, Steve Wofsy

School of Natural Resources: Faculty Publications

Differences in the seasonal pattern of assimilatory and respiratory processes are responsible for divergences in seasonal net carbon exchange among ecosystems. Using FLUXNET data (http://www.eosdis.ornl.gov/FLUXNET) we have analyzed seasonal patterns of gross primary productivity (FGPP), and ecosystem respiration (FRE) of boreal and temperate, deciduous and coniferous forests, Mediterranean evergreen systems, a rainforest, temperate grasslands, and C3 and C4 crops. Based on generalized seasonal patterns classifications of ecosystems into vegetation functional types can be evaluated for use in global productivity and climate change models. The results of this study contribute to our understanding …

Go to article

First Prev Next Last