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Role of eastward propagating convection systems in the diurnal cycle and seasonal mean summertime rainfall over the U. S. Great Plains

Description: By diagnosing the 3-hourly North American Regional Reanalysis rainfall dataset for the 1979-2003 period, it is illustrated that the eastward propagation of convection systems from the Rockies to the Great Plains plays an essential role for the warm season climate over the central U.S. This eastward propagating mode could be the deciding factor for the observed nocturnal rainfall peak over the Great Plains. The results also suggest that nearly half of the total summer mean rainfall over this region is associated with these propagating convection systems. For instance, the extreme wet condition of the 1993 summer may be attributed to the frequent occurrence of propagating convection events and enhanced diurnal rainfall amplitude over the Great Plains. Thus, proper representation of this important propagating component in GCMs is essential for simulating the diurnal and seasonal mean characteristics of summertime rainfall over the central US.
Date: June 7, 2006
Creator: Jiang, X; Lau, N C & Klein, S A
Partner: UNT Libraries Government Documents Department

High and Low Temperatures

Description: "The indicator describes trends in unusually hot and cold temperatures across the United States."
Date: August 2016
Creator: United States. Environmental Protection Agency.
Partner: UNT Libraries Government Documents Department

Fossil and Contemporary Fine Carbon Fractions at 12 Rural and Urban Sites in the United States

Description: Fine particulate matter collected at two urban, four near-urban, and six remote sites throughout the United States were analyzed for total carbon (TC) and radiocarbon ({sup 14}C). Samples were collected at most sites for both a summer and winter season. The radiocarbon was used to partition the TC into fossil and contemporary fractions. On average, contemporary carbon composed about half of the carbon at the urban, {approx}70-97% at near-urban, and 82-100% at remote sites. At Phoenix, Arizona, and Seattle, Washington, one monitor was located within the urban center and one outside to assess the urban excess over background concentrations. During the summer the urban and rural sites had similar contemporary carbon concentrations. However, during the winter the urban sites had more than twice the contemporary carbon measured at the neighboring sites, indicating anthropogenic contributions to the contemporary carbon. The urban fossil carbon was 4-20 times larger than the neighboring rural sites for both seasons. Organic (OC) and elemental carbon (EC) from TOR analysis were available. These and the radiocarbon data were used to estimate characteristic fossil and contemporary EC/TC ratios for the winter and summer seasons. These ratios were applied to carbon data from the Interagency Monitoring of Protected Visual Environments network to estimate the fraction of contemporary carbon at mostly rural sites throughout the United States. In addition, the ratios were used to develop a semiquantitative, lower bound estimate of secondary organic carbon (SOC) contribution to fossil and contemporary carbon. SOC accounted for more than one-third of the fossil and contemporary carbon.
Date: March 1, 2007
Creator: Schichtel, B; Malm, W; Bench, G; Fallon, S; McDade, C & Chow, J
Partner: UNT Libraries Government Documents Department

Meteorology-induced variations in the spatial behavior of summer ozone pollution in Central California

Description: Cluster analysis was applied to daily 8 h ozone maxima modeled for a summer season to characterize meteorology-induced variations in the spatial distribution of ozone. Principal component analysis is employed to form a reduced dimension set to describe and interpret ozone spatial patterns. The first three principal components (PCs) capture {approx}85% of total variance, with PC1 describing a general spatial trend, and PC2 and PC3 each describing a spatial contrast. Six clusters were identified for California's San Joaquin Valley (SJV) with two low, three moderate, and one high-ozone cluster. The moderate ozone clusters are distinguished by elevated ozone levels in different parts of the valley: northern, western, and eastern, respectively. The SJV ozone clusters have stronger coupling with the San Francisco Bay area (SFB) than with the Sacramento Valley (SV). Variations in ozone spatial distributions induced by anthropogenic emission changes are small relative to the overall variations in ozone amomalies observed for the whole summer. Ozone regimes identified here are mostly determined by the direct and indirect meteorological effects. Existing measurement sites are sufficiently representative to capture ozone spatial patterns in the SFB and SV, but the western side of the SJV is under-sampled.
Date: June 23, 2010
Creator: Jin, Ling; Harley, Robert A. & Brown, Nancy J.
Partner: UNT Libraries Government Documents Department

Avian use of Norris Hill Wind Resource Area, Montana

Description: This document presents results of a study of avian use and mortality in and near a proposed wind resource area in southwestern Montana. Data collected in autumn 1995 through summer 1996 represented preconstruction condition; it was compiled, analyzed, and presented in a format such that comparison with post-construction data would be possible. The primary emphasis of the study was recording avian migration in and near the wind resource area using state-of-the-art marine surveillance radar. Avian use and mortality were investigated during the breeding season by employing traditional avian sampling methods, radiotelemetry, radar, and direct visual observation. 61 figs., 34 tabs.
Date: July 1, 1998
Creator: Harmata, A.; Podruzny, K. & Zelenak, J.
Partner: UNT Libraries Government Documents Department

Long-Term Predictions of Global Climate Using the Ocean Conveyor

Description: Many have attributed the Great Ocean Conveyor as a major driver of global climate change over millennia as well as a possible explanation for shorter (multidecadal) oscillations. The conveyor is thought to have a cycle time on the order of 1000 years, however recent research has suggested that it is much faster than previously believed (about 100 years). A faster conveyor leads to the possibility of the conveyor's role in even shorter oscillations such as the El Nino/Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO). The conveyor is primarily density driven. In this study the salty outflow of the Red Sea is used to predict its behavior ten years into the future. A successful model could lead to a long-term prediction (ten years) of El Ninos, Atlantic hurricane season intensity, as well as global temperature and precipitation patterns.
Date: January 1, 2003
Creator: Ray, P. & Wilson, J.R.
Partner: UNT Libraries Government Documents Department

1958-2006 Precipitation Climatology for Lawrence Livermore National Laboratory Livermore Site and Site 300

Description: This report contains rainfall climatology and analyses during the period from 1958 to 2006 for the two sites of Lawrence Livermore National Laboratory: the Livermore site and Site 300. The measurement sites are described, a regional climatology overview is provided, and the effect of topography on regional precipitation is discussed. Rainfall statistics are presented including monthly normals (30-year means) and medians; percentages of time that rainfall is less than or equal to specified amounts for given months, years, and seasons; and mean, median, and maximum numbers of days of precipitation for specified amounts by month, year, and season. The rainfall pattern is demonstrated to be typical of Mediterranean climates, with most rain falling during the cold season. Nearly 80% of seasonal rainfall occurs during November through March, with the average annual rainfall equaling 13.62 and 10.64 inches at the Livermore site and Site 300, respectively. Precipitation frequency and extreme value analyses for durations ranging from 15 minutes to 24 hours, month, and rainfall season are shown in order to estimate rainfall amounts for return periods of two to 100 years at both sites. This analysis determined 100-year return periods for largest 24-hour rainfalls of 2.49 and 2.22 inches at the Livermore site and Site 300, respectively. Historical analysis of seasonal rainfall data indicates that the wettest rainfall seasons at both sites typically occurred during strong El Ninos.
Date: December 19, 2006
Creator: Bowen, B M
Partner: UNT Libraries Government Documents Department

Asotin Creek ISCO Water Sample Data Summary: Water Year 2002, Annual Report 2001-2002.

Description: The Pomeroy Ranger District operates 3 automated water samplers (ISCOs) in the Asotin Creek drainage in cooperation with the Asotin Model Watershed. The samplers are located on Asotin Creek: Asotin Creek at the mouth, Asotin Creek at Koch site, and South Fork Asotin Creek above the forks. At the end of Water Year (WY) 2001 we decided to sample from Oct. 1 through June 30 of each water year. This decision was based on the difficulty of obtaining good low flow samples, since the shallow depth of water often meant that instrument intakes were on the bed of the river and samples were contaminated with bed sediments. The greatest portion of suspended sediment is transported during the higher flows of fall and especially during the spring snow runoff period, and sampling the shorter season should allow characterization of the sediment load of the river. The ISCO water samplers collected a daily composite sample of 4 samples per day into one bottle at 6-hour intervals until late March when they were reprogrammed to collect 3 samples per day at 8-hour intervals. This was done to reduce battery use since battery failure had become an ongoing problem. The water is picked up on 24-day cycles and brought to the Forest Service Water Lab in Pendleton, OR. The samples are analyzed for total suspended solids (TSS), conductivity, and turbidity. A total dissolved solids value is estimated based on conductivity. The USGS gage, Asotin Creek at the mouth, No.13335050 has been discontinued and there are no discharge records available for this period.
Date: August 1, 2003
Creator: Peterson, Stacia
Partner: UNT Libraries Government Documents Department

An Analysis of Wintertime Winds in Washington, D.C.

Description: This report consists of a description of the wintertime climatology of wind speed and wind direction around the National Mall in Washington, D.C. Meteorological data for this study were collected at Ronald Reagan Washington National Airport (Reagan National), Dulles International Airport (Dulles), and a set of surface meteorological stations that are located on a number of building tops around the National Mall. A five-year wintertime climatology of wind speed and wind direction measured at Reagan National and Dulles are presented. A more detailed analysis was completed for the period December 2003 through February 2004 using data gathered from stations located around the National Mall, Reagan National, and Dulles. Key findings of our study include the following: * There are systematic differences between the wind speed and wind direction observed at Reagan National and the wind speed and wind direction measured by building top weather stations located in the National Mall. Although Dulles is located much further from the National Mall than Reagan National, there is better agreement between the wind speed and wind direction measured at Dulles and the weather stations in the National Mall. * When the winds are light (less than 3 ms-1 or 7 mph), there are significant differences in the wind directions reported at the various weather stations within the Mall. * Although the mean characteristics of the wind are similar at the various locations, significant, short-term differences are found when the time series are compared. These differences have important implications for the dispersion of airborne contaminants. In support of wintertime special events in the area of the National Mall, we recommend placing four additional meteorological instruments: three additional surface stations, one on the east bank of the Potomac River, one south of the Reflecting Pool (to better define the flow within the Mall), and a ...
Date: June 20, 2006
Creator: Berg, Larry K. & Allwine, K Jerry
Partner: UNT Libraries Government Documents Department

A brief survey on climate change effects on the Indian Monsoon

Description: Each year, Indian summer monsoon season begins in June and ends in September. Surface winds blow from the southwest during this season. The Indian summer monsoon typically covers large areas of India with western and central India receiving more than 90% of their total annual precipitation during this period, and southern and northwestern India receiving 50%-75% of their total annual rainfall. Overall, monthly totals average 200-300 mm over the country as a whole, with the largest values observed during the heart of the monsoon season in July and August. In all total, India receives about 870 mm of rainfall in a normal summer monsoon season. This summary discusses the effects of climate change on the frequency, mean rainfall, duration and the variability of the Indian Monsoon. East Asian Monsoon in the southeastern part of Asia is not discussed in this summary. Changes in monsoon characteristics are mainly inferred from climate model simulations submitted to the Intergovernmental Panel on Climate Change (IPCC)'s Fourth Assessment Report (AR4). It should be cautioned that there is a large range in the results from these models. For instance, the range of mean monsoon precipitation as simulated by the AR4 models over India is from 500 mm to 900 mm for the present-day climate (Kirpalani et al. 2006).
Date: February 6, 2007
Creator: Bala, G
Partner: UNT Libraries Government Documents Department

Columbia Plateau Basin and Fifteenmile Subbasin Water Rights Acquisitons; Oregon Water Trust Combined Work Plan, 2002-2003 Final Report.

Description: This is the Final Report submitted regarding Oregon Water Trust's Combined Work Plan for fiscal year 2003, with the contract period April 2002 to May 2003. Of this 12 month period, six month were spent concluding our work for the 2002 irrigation season and six months were spent preparing for the 2003 irrigation season. After this grant was completed, projects were finished with funding from the Columbia Basin Water Transactions Program. Many of the 2003 irrigation season successes began in the fall of 2002, when projects were researched and partnerships were developed. Trout Creek Ranch was one of the large successes. During the 2003 irrigation season, 2.6 cfs was leased which led to a permanent instream transfer, protecting critical spawning habitat for summer steelhead in the Deschutes basin. Another success was the Walla Walla Lease Bank project. This project is an agreement between the OWT, the Walla Walla Irrigation District and 11 individual landowners. Through this single year lease, 7.9 cfs of water was legally protected in the Walla Walla River. The Vidando lease on Middle Fork John Day River was renewed for 2 more years, protecting 11.29 cfs. An innovative single year split-season lease was conducted with Voight on Standard Creek in the John Day basin to protect 4.93 cfs. Many other deals were conducted and the total was an impressive 50.43 cfs instream during 2003 and 9.39 cfs pending approval for the 2004 season. Included is a summary of the activities within the Fifteenmile subbasin and the Columbia Plateau basin by quarter and two tables. The summary of activities is broken down by objectives and quarters. The first summarizes the total cfs by type of lease or transfer. The second table lists all the projects by subbasin and provides project type, lease number, cfs, cost of acquisition, partners ...
Date: December 1, 2003
Creator: Paulus, Fritz
Partner: UNT Libraries Government Documents Department

Lower Granite Dam Smolt Monitoring Program, Annual Report 2005-2006.

Description: The 2005 fish collection season at Lower Granite Dam (LGR) was characterized by average water temperatures, below average flows, above average spill, low levels of debris and the record number of smolts collected compared to the previous five years. With the continued release of unclipped supplementation chinook and steelhead above LGR, we cannot accurately distinguish wild chinook, steelhead, and sockeye/kokanee in the sample. For the purposes of this report we will designate fish as clipped and unclipped. This season a total of 13,030,967 juvenile salmonids were collected at LGR. Of these, 12,099,019 were transported to release sites below Bonneville Dam, 12,032,623 by barge and 66,396 by truck. An additional 898,235 fish were bypassed to the river due to over-capacity of the raceways, barges or trucks and for research purposes. This was the first season of summer spill at LGR. Spill was initiated at 12:01am June 20 as directed by the ruling set forth by Judge James Redden of the United States District Court (Order CV 01-640-RE). In addition, the Lower Granite project also conducted a summer spill test alternating spill and spill patterns between spill to the gas cap without the removable spillway weir (RSW) and spill with up to 20 kcfs utilizing the RSW. Because of the forecast low flow this year, most hatchery reared subyearling fall chinook were released up to three weeks early. With the unexpected high flows in late May and early June, more than 90% of the subyearling chinook were collected prior to the initiation of the court ordered summer spill program. Collection number fluctuations reflect river flow and project operations for any given year. For example, low flow years (2001, 2004 and 2005) result in higher collection numbers. Court ordered spill throughout the summer migration will directly affect collection of fall subyearling chinook collection ...
Date: January 1, 2007
Creator: Menski, Fred
Partner: UNT Libraries Government Documents Department

Determining Lamprey Species Composition, Larval Distribution and Adult Abundance in the Deschutes River Subbasin, Oregon ; 2007 Annual Report.

Description: We will report results of an ongoing project in the Deschutes River Subbasin to describe Pacific lamprey (Lampetra tridentata) life history. Project objectives were to determine adult lamprey escapement from Sherars Falls located at Rkm 70.4 and determine lamprey focal spawning areas, spawn timing and habitat through radio telemetry. A mark-recapture study and tribal creel was conducted to determine adult escapement. Lamprey were radio tagged and are currently being mobile, aerial and fixed site tracked to describe spawning. Adult lamprey were collected at Sherars Falls using a long-handled dip net from June-September 2007. The fate of lamprey collected at Sherars Falls was determined based on girth measurements. Fish measuring less than 10.5 cm received two markings for the mark-recapture estimation while those measuring 10.5 cm or greater were implanted with radio transmitters. Two-hundred and nine lamprey were marked during first event sampling, 2,501 lamprey inspected for marks and 64 recaptured during second event sampling. We estimate lamprey abundance to be 8,083 (6,352-10,279) with a relative precision of 19.8. Tribal harvest was 2,303 +/- 88. Escapement was estimated at 5,780 adult lamprey. Thirty-six lamprey received radio transmitters. Lamprey were transported upstream 6.3 Rkm for surgery, held to recover from anesthesia and released. Mobile tracking efforts started mid-July 2007 and are on-going. To date 35 of the 36 lamprey have been detected. Upon release, extensive ground-based tracking was conducted until fish became dormant in mid-October. Since, fixed site downloading and tracking have occurred weekly on the mainstem Deschutes River. Majority of lamprey (88%) are holding in the mainstem Deschutes River. Three lamprey moved upstream more than 70 Rkms into westside tributaries from August-December. Three moved approximately 18 Rkms downstream of the release site. Tracking will continue through the spawning season when redd characteristics will be measured and reported in the 2008-2009 annual ...
Date: June 26, 2009
Creator: Fox, Matt & Graham, Jennifer C.
Partner: UNT Libraries Government Documents Department

Evaluation of Fish Movements, Migration Patterns, and Population Abundance with Streamwidth PIT Tag Interrogation Systems, Final Report 2002.

Description: Two remote Streamwidth PIT tag Interrogation systems (SPIs) were operated continuously for over one year to test the feasibility of these systems for generating movement, migration, survival and smolt production estimates for salmonids. A total of 1,588 juvenile (< 100 mm FL) naturally produced salmonids (7 coho salmon, 482 cutthroat trout, and 1,099 steelhead) were PIT tagged above the upstream-most SPI (9 sites approximately 1 linear km each) in Fall 2001. Age at tagging for wild caught cutthroat and steelhead was 1 year. SPIs were operating before any PIT tagged fish were released in the creek. Over 390,000 detections were recorded from October 2001 to 31 July 2002. Efficiencies were site dependent, but overall detection efficiency for the creek was 97% with 95% confidence intervals of 91-100%. PIT tag detection efficiency ranged from 55-100% depending on the SPI and varied throughout the year with average efficiencies of 73% and 89%. SPI efficiency of PIT tag detection was not completely dependent on electronics noise levels or environmental conditions. Fish from all tagging locations were detected at the SPIs. Steelhead and cutthroat trout were primarily detected moving in the Spring (April-June) coincident with the anticipated smolt migration. Steelhead were also detected moving past SPIs at lower numbers in the Fall and Winter. Travel time between SPIs (downstream movement) was highly dependent on time of year. Travel time in the Spring was significantly faster (34.4 {+-} 7.0 hours) for all species than during any other time of year (763.1 {+-} 267.0 hours). Steelhead and cutthroat migrating in the Spring were the same age as those that did not migrate in the Spring. Peak of steelhead migration recorded at the two SPIs was 5/11 and 5/12 and the peak in the screw trap was recorded on 5/17. Steelhead smolt production estimates using SPIs (3,802 ...
Date: February 1, 2003
Creator: Zydlewski, Gayle; Winter, Christiane & McClanahan, Dee
Partner: UNT Libraries Government Documents Department

Integrated disposal Facility Sagebrush Habitat Mitigation Project: FY2007 Compensation Area Monitoring Report

Description: This report summarizes the first year survival of sagebrush seedlings planted as compensatory mitigation for the Integrated Disposal Facility Project. Approximately 42,600 bare root seedlings and 26,000 pluglings were planted at a mitigation site along Army Loop Road in February 2007. Initial baseline monitoring occurred in March 2007, and first summer survival was assessed in September 2007. Overall survival was 19%, with bare root survival being marginally better than pluglings (21% versus 14%). Likely major factors contributing to low survival were late season planting and insufficient soil moisture during seedling establishment.
Date: September 1, 2007
Creator: Durham, Robin E. & Sackschewsky, Michael R.
Partner: UNT Libraries Government Documents Department

Scotch Creek Wildlife Area 2007-2008 Annual Report.

Description: The Scotch Creek Wildlife Area is a complex of 6 separate management units located in Okanogan County in North-central Washington State. The project is located within the Columbia Cascade Province (Okanogan sub-basin) and partially addresses adverse impacts caused by the construction of Chief Joseph and Grand Coulee hydroelectric dams. With the acquisition of the Eder unit in 2007, the total size of the wildlife area is now 19,860 acres. The Scotch Creek Wildlife Area was approved as a wildlife mitigation project in 1996 and habitat enhancement efforts to meet mitigation objectives have been underway since the spring of 1997 on Scotch Creek. Continuing efforts to monitor the threatened Sharp-tailed grouse population on the Scotch Creek unit are encouraging. The past two spring seasons were unseasonably cold and wet, a dangerous time for the young of the year. This past spring, Scotch Creek had a cold snap with snow on June 10th, a critical period for young chicks just hatched. Still, adult numbers on the leks have remained stable the past two years. Maintenance of BPA funded enhancements is necessary to protect and enhance shrub-steppe and to recover and sustain populations of Sharp-tailed grouse and other obligate species.
Date: November 3, 2008
Creator: Olson, Jim
Partner: UNT Libraries Government Documents Department

Customer Impact Evaluation for the 2009 Southern California Edison Participating Load Pilot

Description: The 2009 Participating Load Pilot Customer Impact Evaluation provides evidence that short duration demand response events which cycle off air conditioners for less than thirty minutes in a hot, dry environment do not lead to a significant degradation in the comfort level of residents participating in the program. This was investigated using: (1) Analysis of interval temperature data collected from inside residences of select program participants; and (2) Direct and indirect customer feedback from surveys designed and implemented by Southern California Edison at the conclusion of the program season. There were 100 indoor temperature monitors that were acquired by LBNL for this study that transmitted temperature readings at least once per hour with corresponding timestamps during the program season, June-October, 2009. Recorded temperatures were transferred from the onsite telemetry devices to a mesh network, stored, and then delivered to KEMA for analysis. Following an extensive data quality review, temperature increases during each of the thirty demand response test events were calculated for each device. The results are as follows: (1) Even for tests taking place during outside temperatures in excess of 100 degrees Fahrenheit, over 85 percent of the devices measured less than a 0.5 degree Fahrenheit temperature increase indoors during the duration of the event. (2) For the increases that were observed, none was more than 5 degrees and it was extremely rare for increases to be more than 2 degrees. At the end of the testing season SCE and KEMA designed and conducted a survey of the a facilities and public works managers and approximately 100 customers feedback survey to assess the extent the PLP events were noticed or disrupted the comfort level of participants. While only a small sampling of 3 managers and 16 customer surveys were completed, their responses indicate: (1) No customer reported even a ...
Date: May 28, 2010
Creator: Gifford, William; Bodmann, Shawn; Young, Paul; Eto, Joseph H. & Laundergan, Jeremy
Partner: UNT Libraries Government Documents Department

Automated Demand Response and Commissioning

Description: This paper describes the results from the second season of research to develop and evaluate the performance of new Automated Demand Response (Auto-DR) hardware and software technology in large facilities. Demand Response (DR) is a set of activities to reduce or shift electricity use to improve the electric grid reliability and manage electricity costs. Fully-Automated Demand Response does not involve human intervention, but is initiated at a home, building, or facility through receipt of an external communications signal. We refer to this as Auto-DR. The evaluation of the control and communications must be properly configured and pass through a set of test stages: Readiness, Approval, Price Client/Price Server Communication, Internet Gateway/Internet Relay Communication, Control of Equipment, and DR Shed Effectiveness. New commissioning tests are needed for such systems to improve connecting demand responsive building systems to the electric grid demand response systems.
Date: April 1, 2005
Creator: Piette, Mary Ann; Watson, David S.; Motegi, Naoya & Bourassa, Norman
Partner: UNT Libraries Government Documents Department

Effects of CO{sub 2} and nitrogen fertilization on soils planted with ponderosa pine

Description: The effects of elevated CO{sub 2} (ambient, 525, and 700 {micro}l l{sup -1})and N fertilization (0, 10, and 20 g N m{sup 2} yr{sup -1}) on soil pCO{sub 2}, CO{sub 2} efflux, soil solution chemistry, and soil C and nutrients in an open-top chamber study with Pinus ponderosa are described. Soil pCO{sub 2} and CO{sub 2} efflux were significantly greater with elevated CO{sub 2}, at first (second growing season) in the 525 {micro}l l{sup -1} and later (fourth and fifth growing seasons) in the 700 {micro}l l{sup -1} CO{sub 2} treatments. Soil solution HCO{sub 3}{sup -} concentrations were temporarily elevated in the 525 {micro}l l{sup -1} CO{sub 2} treatment during the second growing season, consistent with the elevated pCO{sub 2}. Nitrogen fertilization had no consistent effect on soil pCO{sub 2} or CO{sub 2} efflux, but did have the expected negative effect on exchangeable Ca{sup 2+}, K{sup +}, and Mg{sup 2+}, presumed to be caused by increased nitrate leaching. Elevated CO{sub 2} had no consistent effects on exchangeable Ca{sup 2+}, K{sup +}, and Mg{sup 2+}, but did cause temporary reductions in soil NO{sup 3{sup -}} (second growing season). Statistically significant negative effects of elevated CO{sub 2} on soil extractable P were noted in the third and sixth growing seasons. However, these patterns in extractable P reflected pre-treatment differences, which, while not statistically significant, followed the same pattern. Statistically significant effects of elevated CO{sub 2} on total C and N in soils were noted in the third and sixth growing seasons, but these effects were inconsistent among N treatments and years. The clearest effect of elevated CO{sub 2} was in the case of C/N ratio in year 6, where there was a consistent, positive effect. The increases in C/N ratio with elevated CO{sub 2} in year six were largely a result of ...
Date: December 1, 1996
Creator: Johnson, D.W.
Partner: UNT Libraries Government Documents Department

Investigation of Microphysical Parameters within Winter and Summer Type Precipitation Events over Mountainous [Complex] Terrain

Description: In this study we investigate complex terrain effects on precipitation with RAMS for both in winter and summer cases from a microphysical perspective. We consider a two dimensional east-west topographic cross section in New Mexico representative of the Jemez mountains on the west and the Sangre de Cristo mountains on the east. Located between these two ranges is the Rio Grande Valley. In these two dimensional experiments, variations in DSDs are considered to simulate total precipitation that closely duplicate observed precipitation.
Date: December 31, 1997
Creator: Stalker, James R. & Bossert, James E.
Partner: UNT Libraries Government Documents Department