659 research outputs found
Forecasting Cool Season Daily Peak Winds at Kennedy Space Center and Cape Canaveral Air Force Station
The expected peak wind speed for the day is an important element in the daily 24-Hour and Weekly Planning Forecasts issued by the 45th Weather Squadron (45 WS) for planning operations at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). The morning outlook for peak speeds also begins the warning decision process for gusts ^ 35 kt, ^ 50 kt, and ^ 60 kt from the surface to 300 ft. The 45 WS forecasters have indicated that peak wind speeds are a challenging parameter to forecast during the cool season (October-April). The 45 WS requested that the Applied Meteorology Unit (AMU) develop a tool to help them forecast the speed and timing of the daily peak and average wind, from the surface to 300 ft on KSC/CCAFS during the cool season. The tool must only use data available by 1200 UTC to support the issue time of the Planning Forecasts. Based on observations from the KSC/CCAFS wind tower network, surface observations from the Shuttle Landing Facility (SLF), and CCAFS upper-air soundings from the cool season months of October 2002 to February 2007, the AMU created multiple linear regression equations to predict the timing and speed of the daily peak wind speed, as well as the background average wind speed. Several possible predictors were evaluated, including persistence, the temperature inversion depth, strength, and wind speed at the top of the inversion, wind gust factor (ratio of peak wind speed to average wind speed), synoptic weather pattern, occurrence of precipitation at the SLF, and strongest wind in the lowest 3000 ft, 4000 ft, or 5000 ft. Six synoptic patterns were identified: 1) surface high near or over FL, 2) surface high north or east of FL, 3) surface high south or west of FL, 4) surface front approaching FL, 5) surface front across central FL, and 6) surface front across south FL. The following six predictors were selected: 1) inversion depth, 2) inversion strength, 3) wind gust factor, 4) synoptic weather pattern, 5) occurrence of precipitation at the SLF, and 6) strongest wind in the lowest 3000 ft. The forecast tool was developed as a graphical user interface with Microsoft Excel to help the forecaster enter the variables, and run the appropriate regression equations. Based on the forecaster's input and regression equations, a forecast of the day's peak and average wind is generated and displayed. The application also outputs the probability that the peak wind speed will be ^ 35 kt, 50 kt, and 60 kt
An Analysis of Peak Wind Speed Data from Collocated Mechanical and Ultrasonic Anemometers
This study focuses on a comparison of peak wind speeds reported by mechanical and ultrasonic anemometers at Cape Canaveral Air Force Station and Kennedy Space Center (CCAFS/KSC) on the east central coast of Florida and Vandenberg Air Force Base (VAFB) on the central coast of California. The legacy mechanical wind instruments on CCAFS/KSC and VAFB weather towers are being changed from propeller-and-vane (CCAFS/KSC) and cup-and-vane (VAFB) sensors to ultrasonic sensors under the Range Standardization and Automation (RSA) program. The wind tower networks on KSC/CCAFS and VAFB have 41 and 27 towers, respectively. Launch Weather Officers, forecasters, and Range Safety analysts at both locations need to understand the performance of the new wind sensors for a myriad of reasons that include weather warnings, watches, advisories, special ground processing operations, launch pad exposure forecasts, user Launch Commit Criteria (LCC) forecasts and evaluations, and toxic dispersion support. The Legacy sensors measure wind speed and direction mechanically. The ultrasonic RSA sensors have no moving parts. Ultrasonic sensors were originally developed to measure very light winds (Lewis and Dover 2004). The technology has evolved and now ultrasonic sensors provide reliable wind data over a broad range of wind speeds. However, because ultrasonic sensors respond more quickly than mechanical sensors to rapid fluctuations in speed, characteristic of gusty wind conditions, comparisons of data from the two sensor types have shown differences in the statistics of peak wind speeds (Lewis and Dover 2004). The 45th Weather Squadron (45 WS) and the 30 WS requested the Applied Meteorology Unit (AMU) to compare data from RSA and Legacy sensors to determine if there are significant differences in peak wind speed information from the two systems
An Analysis of Peak Wind Speed Data from Collocated Mechanical and Ultrasonic Anemometers
This study compared peak wind speeds reported by mechanical and ultrasonic anemometers at Cape Canaveral Air Force Station and Kennedy Space Center (CCAFS/KSC) on the east central coast of Florida and Vandenberg Air Force Base (VAFB) on the central coast of California. Launch Weather Officers, forecasters, and Range Safety analysts need to understand the performance of wind sensors at CCAFS/KSC and VAFB for weather warnings, watches, advisories, special ground processing operations, launch pad exposure forecasts, user Launch Commit Criteria (LCC) forecasts and evaluations, and toxic dispersion support. The legacy CCAFS/KSC and VAFB weather tower wind instruments are being changed from propeller-and-vane (CCAFS/KSC) and cup-and-vane (VAFB) sensors to ultrasonic sensors under the Range Standardization and Automation (RSA) program. Mechanical and ultrasonic wind measuring techniques are known to cause differences in the statistics of peak wind speed as shown in previous studies. The 45th Weather Squadron (45 WS) and the 30th Weather Squadron (30 WS) requested the Applied Meteorology Unit (AMU) to compare data between the RSA ultrasonic and legacy mechanical sensors to determine if there are significant differences. Note that the instruments were sited outdoors under naturally varying conditions and that this comparison was not designed to verify either technology. Approximately 3 weeks of mechanical and ultrasonic wind data from each range from May and June 2005 were used in this study. The CCAFS/KSC data spanned the full diurnal cycle, while the VAFB data were confined to 1000-1600 local time. The sample of 1-minute data from numerous levels on five different towers on each range totaled more than 500,000 minutes of data (482,979 minutes of data after quality control). The ten towers were instrumented at several levels, ranging from 12 ft to 492 ft above ground level. The ultrasonic sensors were collocated at the same vertical levels as the mechanical sensors and typically within 15 ft horizontally of each another. Data from a total of 53 RSA ultrasonic sensors, collocated with mechanical sensors were compared. The 1- minute average wind speed/direction and the 1-second peak wind speed/direction were compared
Using Annual Landsat Time Series for the Detection of Dry Forest Degradation Processes in South-Central Angola
Dry tropical forests undergo massive conversion and degradation processes.
This also holds true for the extensive Miombo forests that cover large parts
of Southern Africa. While the largest proportional area can be found in
Angola, the country still struggles with food shortages, insufficient medical
and educational supplies, as well as the ongoing reconstruction of
infrastructure after 27 years of civil war. Especially in rural areas, the
local population is therefore still heavily dependent on the consumption of
natural resources, as well as subsistence agriculture. This leads, on one
hand, to large areas of Miombo forests being converted for cultivation
purposes, but on the other hand, to degradation processes due to the selective
use of forest resources. While forest conversion in south-central rural Angola
has already been quantitatively described, information about forest
degradation is not yet available. This is due to the history of conflicts and
the therewith connected research difficulties, as well as the remote location
of this area. We apply an annual time series approach using Landsat data in
south-central Angola not only to assess the current degradation status of the
Miombo forests, but also to derive past developments reaching back to times of
armed conflicts. We use the Disturbance Index based on tasseled cap
transformation to exclude external influences like inter-annual variation of
rainfall. Based on this time series, linear regression is calculated for
forest areas unaffected by conversion, but also for the pre-conversion period
of those areas that were used for cultivation purposes during the observation
time. Metrics derived from linear regression are used to classify the study
area according to their dominant modification processes. We compare our
results to MODIS latent integral trends and to further products to derive
information on underlying drivers. Around 13% of the Miombo forests are
affected by degradation processes, especially along streets, in villages, and
close to existing agriculture. However, areas in presumably remote and dense
forest areas are also affected to a significant extent. A comparison with
MODIS derived fire ignition data shows that they are most likely affected by
recurring fires and less by selective timber extraction. We confirm that areas
that are used for agriculture are more heavily disturbed by selective use
beforehand than those that remain unaffected by conversion. The results can be
substantiated by the MODIS latent integral trends and we also show that due to
extent and location, the assessment of forest conversion is most likely not
sufficient to provide good estimates for the loss of natural resources. View
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Applied Meteorology Unit - Operational Contributions to Spaceport Canaveral
The Applied Meteorology Unit (AMU) provides technology development, evaluation and transition services to improve operational weather support to the Space Shuttle and the National Space Program. It is established under a Memorandum of Understanding among NASA, the Air Force and the National .Weather Service (NWS). The AMU is funded and managed by NASA and operated by ENSCO, Inc. through a competitively awarded NASA contract. The primary customers are the 45th Weather Squadron (45WS) at Cape Canaveral Air Force Station (CCAFS), FL; the Spaceflight Meteorology Group (SMG) at Johnson Space Center (JSC) in Houston, TX; and the NWS office in Melbourne, FL (NWS MLB). This paper will briefly review the AMU's history and describe the three processes through which its work is assigned. Since its inception in 1991 the AMU has completed 72 projects, all of which are listed at the end of this paper. At least one project that highlights each of the three tasking processes will be briefly reviewed. Some of the projects that have been especially beneficial to the space program will also be discussed in more detail, as will projects that developed significant new techniques or science in applied meteorology
Analysis of Epithelial Growth Factor-Receptor (EGFR) Phosphorylation in Uterine Smooth Muscle Tumors
Uterine fibroids are the commonest uterine benign tumors. A potential mechanism of malignant transformation from leiomyomas to leiomyosarcomas has beendescribed. Tyrosine phosphorylation is a key mechanism that controls biological functions, such as proliferation and cell differentiation. The aim of the current study was to evaluate the phosphorylation of epithelial growth factor-receptor (EGFR) in normal myometrium, uterine myomas and uterine leiomyosarcomas. Formalin-fixed paraffin-embedded tissue samples from normal myometrium, leiomyomas and leiomyosarcomas were studied. Samples were immunohistochemically (IHC) assessed using the anti-EGFR phosphorylation of Y845 (pEGFR-Y845) and anti-pEGFR-Y1173 phosphorylation-specific antibodies. IHC staining was evaluated using a semiquantitative score. The expression of pEGFR-Y845 was significantly upregulated in leiomyosarcomas (p < 0.001) compared to leiomyomas and normal myometrium. In contrast, pEGFR-Y1173 did not differ significantly between the three groups of the study. Correlation analysis revealed an overall positive correlation between pEGFR Y845 and mucin 1 (MUC1). Further subgroup analysis within the tumoral group (myomas and leiomyosarcomas) revealed an additional negative correlation between pEGFR Y845 and galectin-3 (gal-3) staining. On the contrary no significant correlation was noted within the non-tumoral group. An upregulated EGFR phosphorylation of Y845 in leiomyosarcomas compared to leiomyomas implicates EGFR activation at this special receptor site. Due to these pEGFR-Y845 variations, it can be postulated that MUC1 interacts with it, whereas gal-3 seems to be cleaved from Y845 phosphorylated
EGFR. Further research on this field could focus on differences in EGFR pathways as a potentially advantageous diagnostic tool for investigation of benign and malignant signal transduction processes
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