In July 2002, a multi-sensor campaign was conducted in southern France to investigate the hypothesized connection between
gravity waves and optical turbulence. A generalized scidar (GS) was mounted on the 1.93 m diameter telescope at l’Observatoire
de Haute-Provence (OHP). The GS provides continuous profiles of optical turbulence with 300 m vertical resolution from telescope
altitude up to 25 km. Thermosondes, which provide in situ measurement of optical turbulence by measuring temperature variance,
were launched at the OHP site and at a site approximately 20 km west-northwest of OHP. Gravity wave activity was deduced from
temperature and wind velocity measured by radiosondes, which are part of the thermosonde system. In this paper, gravity waves
were analyzed using techniques for simple two-dimensional mountain waves, with only fair results. Mesoscale models were run
at moderately high resolution for the period. The forecasts were analyzed for wave activity, and a post processor model was
used to diagnose the optical turbulence. Mountain waves were evident in the forecast, but quantitative comparison showed the
forecast to be inadequate in predicting wave strength. The forecast optical turbulence was in fair agreement with measurements
with notable exceptions.
This paper is declared a work of the U.S. Government and is not subject to copyright protection in the United States. The
U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.
Presented at the Turbulence and Waves in Stably Stratified Atmospheric Shear Flows: Measurements, High Resolution Simulations
and Numerical Prediction Challenges Conference, 13–15 September 2004, Lighthill Institute of Mathematical Sciences, University
College London, London, UK. 相似文献
This study is premised on Indonesia’s climate goal amidst good economic performance. To test the environmental implication of this macroeconomic performance of Indonesia, we adopt Indonesian quarterly data of 1990Q1–2018Q4 for empirical analysis. Relevant instruments in the economic performance of Indonesia such as urbanization, foreign direct investment (FDI), and renewable energy source are all adopted for accurate estimations and analysis of this topic. Different approaches (structural break test, autoregressive distributed lag (ARDL)-bounds testing and Granger causality) are all adopted in this study. Our analysis and policy recommendations are based on the short-run and long-run ARDL dynamics and Granger causality. Findings from ARDL confirmed negative relationship between carbon emission and renewable energy source, FDI, and urbanization. Also, a U-shape instead of inverted U-shaped EKC is found confirming the impeding implication of Indonesian economic growth to its environmental performance if not checkmate. From Granger causality analysis, all the variables are seen transmitting to urbanization in a one-way causal relationship. Also, FDI and renewable energy prove to be essential determinants of the country’s environment development; hence, FDI is seen transmitting to both energy sources (fossil fuels and renewables) in a one-way causal relationship. Renewable energy is as well seen having two ways causal relationship with both carbon emission and fossil fuels. This result has equally exposed the significant position of the three instruments (urbanization, FDI, and renewable energy source) in Indonesian environment development.
The phenomenon called cold fusion has been studied for the last 21 years since its discovery by Profs. Fleischmann and Pons in 1989. The discovery was met with considerable skepticism, but supporting evidence has accumulated, plausible theories have been suggested, and research is continuing in at least eight countries. This paper provides a brief overview of the major discoveries and some of the attempts at an explanation. The evidence supports the claim that a nuclear reaction between deuterons to produce helium can occur in special materials without application of high energy. This reaction is found to produce clean energy at potentially useful levels without the harmful byproducts normally associated with a nuclear process. Various requirements of a model are examined. 相似文献
The key issue in achieving a high extent of biodegradation of beet molasses vinasse is to establish the conditions for the assimilation of betaine, which is the main pollutant in this high-strength industrial effluent. In the present study, aerobic batch biodegradation was conducted over the temperature range of 27-63°C (step 9°C), at a pH of 6.5 and 8.0, using a mixed culture of bacteria of the genus Bacillus. Betaine was assimilated at 27-54°C and the pH of 8.0, as well as at 27-45°C and the pH of 6.5. The processes where betaine was assimilated produced a high BOD(5) removal, which exceeded 99.40% over the temperature range of 27-45°C at the pH of 8.0, as well as at 27°C and the pH of 6.5. Maximal COD removal (88.73%) was attained at 36°C and the pH of 6.5. The results indicate that the process can be applied on an industrial scale as the first step in the treatment of beet molasses vinasse. 相似文献
Silver nanoparticles (NP) are used in several applications, including their use as antimicrobial agents in textiles, personal care, and other domestic products. As such, there is a high potential for the release of silver nanoparticles (AgNP) in the aquatic environment. In aquatic ecosystems, nanomaterials are affected by abiotic factors, such as temperature, that alter their chemistry and influence their fate in the environment. Preliminary studies indicate that NP tend to form aggregates which are potentially more recalcitrant than unaggregated NP. These and other fate processes are largely dependent on both the characteristics of the NP and that of the environment. In this study, lab experiments were conducted to investigate the physicochemical properties and temperature solubility of AgNP (<100 nm) that may potentially influence the fate and behavior of AgNP in the aqueous environment. Results indicated that, under these tested conditions, AgNP may be transformed in size and thereby affect fate, bioavailability, and toxicity. In this study, a novel method was used to determine whether AgNP would form agglomerates, or behave as isolated particles, or dissolve when in aqueous media and under different environmental conditions. The new aspects evaluated in this study demonstrated that AgNP are transformed in both size and state under variable environmental conditions. 相似文献
Herein we present a campaign dedicated to the detection and the characterization of Gravity Waves (GW) in the Earth’s atmosphere
in relation to the generation of Optical Turbulence (OT). The observations took place in France from 17 to 24 July 2002 at
the Haute Provence Observatory (OHP) and simultaneously at the Sirene Observatory, some 20 km apart. From both sites, several
balloons were launched that measured the classical PTU-Wind profiles and additionally the structure constant of the temperature
field vertical profiles. A Generalized Scidar (GS) technique was implemented at the 1.93 m-diameter OHP telescope, providing profiles every minute. From our observations, a significant amount of GW activity was observed at both sites, but without
clear evidence of correlation between the two sites. It seems from our observations that a wide spectrum of GW is present
at a given altitude and that this could result in a lack of correlation between observations made from two sites 20 km apart.
Most GW are non-stationary with long horizontal wavelengths (λ ∼ 100–200 km), kilometric vertical wavelengths (λ ~ 0.5–2 km)
and long intrinsic period (T ~ 2–15 h). They belong in the category of “hydrostatic rotating or non-rotating waves”. Layers of optical turbulence detected
by balloons and the Scidar technique correlate well with regions of GW activity.
The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
Regional Environmental Change - Present day and future social vulnerability, flood risk, and disadvantage across the UK are explored using the UK Future Flood Explorer. In doing so, new indices of... 相似文献