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Laurentide Ice Sheet meltwater and abrupt climate change during the last glaciation (open access)

Laurentide Ice Sheet meltwater and abrupt climate change during the last glaciation

A leading hypothesis to explain abrupt climate change during the last glacial cycle calls on fluctuations in the margin of the North American Laurentide Ice Sheet (LIS), which may have routed freshwater between the Gulf of Mexico (GOM) and North Atlantic, affecting North Atlantic Deep Water (NADW) variability and regional climate. Paired measurements of {delta}O and Mg/Ca of foraminiferal calcite from GOM sediments reveal five episodes of LIS meltwater input from 28-45 thousand years ago (ka) that do not match the millennial-scale Dansgaard-Oeschger (D/O) warmings recorded in Greenland ice. We suggest that summer melting of the LIS may occur during Antarctic warming and likely contributed to sea-level variability during Marine Isotope Stage 3 (MIS 3).
Date: October 2, 2005
Creator: Hill, H W; Flower, B P; Quinn, T M; Hollander, D J & Guilderson, T P
Object Type: Article
System: The UNT Digital Library
Comment on "Radiocarbon Calibration Curve Spanning 0 to 50,000 Years B.P. Based on Paired 230Th/234U/238U and 14C Dates on Pristine Corals" by R.G. Fairbanks, R. A. Mortlock, T.-C. Chiu, L. Cao, A. Kaplan, T. P. Guilderson, T. W. Fairbanks, A. L. Bloom, P (open access)

Comment on "Radiocarbon Calibration Curve Spanning 0 to 50,000 Years B.P. Based on Paired 230Th/234U/238U and 14C Dates on Pristine Corals" by R.G. Fairbanks, R. A. Mortlock, T.-C. Chiu, L. Cao, A. Kaplan, T. P. Guilderson, T. W. Fairbanks, A. L. Bloom, P

Radiocarbon calibration curves are essential for converting radiocarbon dated chronologies to the calendar timescale. Prior to the 1980's numerous differently derived calibration curves based on radiocarbon ages of known age material were in use, resulting in ''apples and oranges'' comparisons between various records (Klein et al., 1982), further complicated by until then unappreciated inter-laboratory variations (International Study Group, 1982). The solution was to produce an internationally-agreed calibration curve based on carefully screened data with updates at 4-6 year intervals (Klein et al., 1982; Stuiver and Reimer, 1986; Stuiver and Reimer, 1993; Stuiver et al., 1998). The IntCal working group has continued this tradition with the active participation of researchers who produced the records that were considered for incorporation into the current, internationally-ratified calibration curves, IntCal04, SHCal04, and Marine04, for Northern Hemisphere terrestrial, Southern Hemisphere terrestrial, and marine samples, respectively (Reimer et al., 2004; Hughen et al., 2004; McCormac et al., 2004). Fairbanks et al. (2005), accompanied by a more technical paper, Chiu et al. (2005), and an introductory comment, Adkins (2005), recently published a ''calibration curve spanning 0-50,000 years''. Fairbanks et al. (2005) and Chiu et al. (2005) have made a significant contribution to the database on which the IntCal04 …
Date: October 2, 2005
Creator: Reimer, P. J.; Baillie, M. L.; Bard, E.; Beck, J. W.; Blackwell, P. G.; Buck, C. E. et al.
Object Type: Article
System: The UNT Digital Library
Polk County Enterprise (Livingston, Tex.), Vol. 123, No. 79, Ed. 1 Sunday, October 2, 2005 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 123, No. 79, Ed. 1 Sunday, October 2, 2005

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: October 2, 2005
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Seminole Sentinel (Seminole, Tex.), Vol. 96, No. 102, Ed. 1 Sunday, October 2, 2005 (open access)

Seminole Sentinel (Seminole, Tex.), Vol. 96, No. 102, Ed. 1 Sunday, October 2, 2005

Semi-weekly newspaper from Seminole, Texas that includes local, state, and national news along with extensive advertising.
Date: October 2, 2005
Creator: Wright, Dustin
Object Type: Newspaper
System: The Portal to Texas History
Evaluation of the Emission, Transport, and Deposition of Mercury, Fine Particulate Matter, and Arsenic from Coal-Based Power Plants in the Ohio River Valley Region (open access)

Evaluation of the Emission, Transport, and Deposition of Mercury, Fine Particulate Matter, and Arsenic from Coal-Based Power Plants in the Ohio River Valley Region

Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, is evaluating the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury, arsenic, and associated fine particulate matter. This evaluation will involve two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring will include the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM station will contain sampling equipment to collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), arsenic, particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NOx, SO{sub 2}, O{sub 3}, etc.). Laboratory analysis of time-integrated samples will be used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Near-real-time measurements will be used to measure the ambient concentrations of PM mass and all gaseous species including Hg{sup 0} and RGM. Approximately of 18 months of field data will be collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal …
Date: October 2, 2005
Creator: Crist, Kevin
Object Type: Report
System: The UNT Digital Library
QCD CORRECTIONS TO DILEPTON PRODUCTION NEAR PARTONIC THRESHOLD IN PP SCATTERING. (open access)

QCD CORRECTIONS TO DILEPTON PRODUCTION NEAR PARTONIC THRESHOLD IN PP SCATTERING.

We present a recent study of the QCD corrections to dilepton production near partonic threshold in transversely polarized {bar p}p scattering, We analyze the role of the higher-order perturbative QCD corrections in terms of the available fixed-order contributions as well as of all-order soft-gluon resummations for the kinematical regime of proposed experiments at GSI-FAIR. We find that perturbative corrections are large for both unpolarized and polarized cross sections, but that the spin asymmetries are stable. The role of the far infrared region of the momentum integral in the resummed exponent and the effect of the NNLL resummation are briefly discussed.
Date: October 2, 2005
Creator: SHIMIZU, H.; STERMAN, G.; VOGELSANG, W. & YOKOYA, H.
Object Type: Article
System: The UNT Digital Library
Carbon Sequestration on Surface Mine Lands (open access)

Carbon Sequestration on Surface Mine Lands

During this quarter a general forest monitoring program was conducted to measure treatment effects on above ground and below ground carbon C and Nitrogen (N) pools for the tree planting areas. Detailed studies to address specific questions pertaining to Carbon cycling was initiated with the development of plots to examine the influence of mycorrhizae, spoil chemical and mineralogical properties, and use of amendment on forest establishment and carbon sequestration. Efforts continued during this period to examine decomposition and heterotrophic respiration on C cycling in the reforestation plots. Projected climate change resulting from elevated atmospheric carbon dioxide has given rise to various strategies to sequester carbon in various terrestrial ecosystems. Reclaimed surface mine soils present one such potential carbon sink where traditional reclamation objectives can complement carbon sequestration. New plantings required the modification and design and installation on monitoring equipment. Maintenance and data monitoring on past and present installations are a continuing operation. The Department of Mining Engineering continued the collection of penetration resistance, penetration depth, and bulk density on both old and new treatment areas. Data processing and analysis is in process for these variables. Project scientists and graduate students continue to present results at scientific meetings, tours and field …
Date: October 2, 2005
Creator: Graves, Donald H.; Barton, Christopher; Sweigard, Richard & Warner, Richard
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 107, No. 156, Ed. 1 Sunday, October 2, 2005 (open access)

Altus Times (Altus, Okla.), Vol. 107, No. 156, Ed. 1 Sunday, October 2, 2005

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: October 2, 2005
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History

[Baseball player in vintage clothes]

Photograph of a man preparing to throw a baseball while wearing a vintage outfit and standing at the edge of a field in Abilene, Texas.
Date: October 2, 2005
Creator: Mallory, Randy
Object Type: Photograph
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, October 2, 2005 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, October 2, 2005

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: October 2, 2005
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 91, No. 15, Ed. 1 Sunday, October 2, 2005 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 91, No. 15, Ed. 1 Sunday, October 2, 2005

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: October 2, 2005
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 299, Ed. 1 Sunday, October 2, 2005 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 299, Ed. 1 Sunday, October 2, 2005

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: October 2, 2005
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Panola Watchman (Carthage, Tex.), Vol. 132, No. 75, Ed. 1 Sunday, October 2, 2005 (open access)

The Panola Watchman (Carthage, Tex.), Vol. 132, No. 75, Ed. 1 Sunday, October 2, 2005

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.
Date: October 2, 2005
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History

[Holding vintage baseball]

Photograph of a man holding a vintage "base ball" in Abilene, Texas while standing in a field. He is preparing to swing the bat while looking towards the right side of the photo.
Date: October 2, 2005
Creator: Mallory, Randy
Object Type: Photograph
System: The UNT Digital Library

[Vintage baseball bat makers]

Photograph of two men posing next to a bucket of vintage baseball bats while leaning against a tree in Abilene, Texas. They appear to be the creators of the bats.
Date: October 2, 2005
Creator: Mallory, Randy
Object Type: Photograph
System: The UNT Digital Library