The response time of an ECC sonde to an ozone concentration step is below one minute. Consequently, the measurement sequence is typically composed of a one-minute spin-up period after the pump has been turned on, followed by a one- to two-minute acquisition period. All time intervals can be adjusted before and during the flight. Results of a preliminary ground-based test in spring are first presented. The sonde provided correct ozone concentrations against a reference UV analyzer every 15 minutes during 4 days.
BLPB drifting. Two Eureka Manta2 3. One of the two sensors was out of compliance by 1. The River Sonde radar makes non-contact measurement of a horizontal swath of surface velocity across a river section. This radar, which has worked successfully at several rivers in the Western USA, has shown encouraging correlation with simultaneous measurements of average currents at one level recorded by an acoustic travel-time system.
e-book Setting Boundaries™ with Your Aging Parents
The primary goal was to begin to explore the robustness of the radar data as a reliable index of discharge. The larger intent of the work is to examine variability in space and time of the radar's surface currents compared with subsurface flows across the river section. Here we examine data from a couple of periods with strong winds. Based upon the 2-D autocorrelation for the tropospheric column ozone anomalies of the OMI swaths, we show that the stratosphere-troposphere exchange STE processes occur on the scale of a few hundred kilometers.
On the other hand, the CTM has great positive biases against satellite observations in the lower stratosphere of winter time southern hemisphere SH mid-latitudes, which is probably attributed to the problems in the stratospheric circulation of the driving met-fields. We found eight cases in year with all the four Aura measurements available and folding structures in the coincident sonde profile. The case studies indicate that all the four Aura instruments demonstrate some skills in catching the.
Rauvolfianine, a new antimycobacterial glyceroglycolipid and other constituents from Rauvolfia caffra.
Sond Apocynaceae. Compounds 1, 2, 3, 4 and 7 were evaluated for antitubercular activity. Their structures and relative stereochemistry were elucidated by spectroscopic methods. Probes and their application to the study of H.
What is Kobo Super Points?
In the first part of this paper, we study the single Langmuir probe and the double-probe method. In the second part, we describe the probe-technique in connection with R. La seconde partie est consacree a la pratique des sondes dans l'etude des plasmoides H. The Sea Sonde Reliable data were obtained from the two radars installed, and successful trials were conducted with the Infosat satellite link to transmit data from the remote site.
Data recovery from the Sea Sonde was generally good, with maximum ranges varying from 15 km to over 30 km. Sea echo return strength at both radars was correlated with wind, consistent with lower Bragg scattering at lower wind speeds. A simple surface current forecasting algorithm, based on decomposing the signal into tidal and residual bands, was examined.
It was found that tides account for the greatest portion of currents in the study area, and could be forecasted out to 48 h with d of input data. The nonpredictable, fluctuating part of the current signal was isolated and its statistics were calculated. The algorithm tests showed that the Sea Sonde data can be used to measure and predict the slowly varying tidal and mean flow velocities, as well as the random part of the signal, both of which are important in oil spill modelling.
Surface flow patterns and time-series data from the Sea Sonde measurements, and from a three-dimensional hydrodynamic model, were compared from an oil spill modelling perspective. In general, surface flow patterns from the model were smoother than those observed. The differences were most noticeable in the cross-channel direction.
The radar data indicate that a flow-dependent eddy viscosity formulation, with coefficients calibrated to reproduce the features observed with the radar, would improve agreement and yield a good model for data assimilation. These plumes have been detected by the Ozone Monitoring Instrument OMI , and evidence of these plumes has also appeared in the in-situ Ticosonde project record: a continuous balloon-borne ozonesonde launch experiment conducted in a weekly basis in Costa Rica.
In the case of the latter, the interference reaction of SO2 in the cathode cell of the standard electrochemical concentration cell ECC ozonesonde results in apparent "notches" in the ozone profile at the altitudes of the plume. In this paper, we present an overview of the Ticosonde observations and correlate the appearance of the notches with air mass back trajectory calculations that link the profiles features to emissions from the volcano.
The integrated column SO2 from the sonde profile data agree well with the OMI overpass data for this event. Data from a tethersonde measurement two days prior to the dual sonde reveal concentrations at the ppm level at the volcanic source. Calibration of langmuir probes by a microwave method; Etalonnage des sondes de langmuir par une methode hyperfrequence. Ozone sonde cell current measurements and implications for observations of near-zero ozone concentrations in the tropical upper troposphere.
Directory of Open Access Journals Sweden. Full Text Available Laboratory measurements of the Electrochemical Concentration Cell ECC ozone sonde cell current using ozone free air as well as defined amounts of ozone reveal that background current measurements during sonde preparation are neither constant as a function of time, nor constant as a function of ozone concentration. Using a background current, measured at a defined timed after exposure to high ozone may often overestimate the real background, leading to artificially low ozone concentrations in the upper tropical troposphere, and may frequently lead to operator dependent uncertainties.
Based on these laboratory measurements an improved cell current to partial pressure conversion is proposed, which removes operator dependent variability in the background reading and possible artifacts in this measurement. In the reprocessed data set near-zero ozone events no longer occur.
Anthologie de New York by unevilledeslivres association - Issuu
To a large extent, these events are no longer observed in the reprocessed data set using the improved background treatment. Geophysical borehole logging, dummy- sonding and optical imaging of the borehole OL-KR24 at Olkiluoto Suomen Malmi Oy conducted geophysical borehole logging, dummy- sonding and optical imaging surveys of the borehole OL-KR24 at the Olkiluoto site in Eurajoki during 1. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The methods applied are caliper survey and optical imaging.
The assignment included the field work of surveys, interpretation and processing of the data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. An electronic probe micro-analyser. A linear scan device; Microanalyseur a sonde electronique.
Dispositif de balayage lineaire. The Castaing electronic probe micro-analyser makes possible static analysis at successive points. For two years this apparatus has been equipped by its constructor with an automatic device for surface scanning. In order to increase the micro-analyser's efficiency a 'linear' scan device has been incorporated making it possible to obtain semi-quantitative analyses very rapidly. Depuis deux ans, cet appareil a ete equipe par son constructeur d'un dispositif de balayage automatique 'surface'.
Afin d'augmenter l'efficacite du microanalyaeur, on a adapte un dispositif de balayage 'lineaire' qui permet d'obtenir tres rapidement des analyses semi-quantitative. The shore-based Sea Sonde high-frequency HF radar was deployed for three weeks in summer to measure surface currents in the Strait of Georgia, British Columbia. Experimental objectives included documenting the complex flow regime generated by large tides and the brackish plume of the Fraser River, and determining the radar performance under low-wind, low-salinity conditions. The radar data showed that surface flows are dominated by the plume jet formed by the Fraser River outflow, giving rise to recurring, energetic eddies with scales of km, strong flow meanders, and convergent fronts.
These features were continuously modulated by the along-channel tidal flows. Comparisons with a detailed numerical model hindcast gave good correlation between observed and predicted flow fields, especially at tidal and low frequencies. Radar return was found to be correlated with local winds and radar performance was independent of salinity variations in the plume.
Synthetic aperture radar SAR provides a map of the radar scattering characteristics of the ocean surface on a capillary wave scale. ERS-1 satellite and airborne SAR images for July 28, were obtained and surface features were examined in the context of the HF radar current fields. Results show that SAR images alone cannot reliably provide the dynamical data required in this region by oil spill models. Under certain conditions, however, the radar imagery offers valuable physical information on phenomena affecting oil slick development. Interpretation of SAR imagery in conjunction with other remote sensing information would offer more quantitative prediction data.
We discuss ground level in-situ measurements of sulphur dioxide SO 2 , sulphuric acid H 2 SO 4 and particulate matter as well as ozone sonde profiles and column measurements of SO 2 by a Brewer spectrometer. At Hohenpeissenberg, a number of reactive gases, e. Our results describe the arrival of the volcanic plume at Zugspitze and Hohenpeissenberg during 16 and 17 April and its residence in the planetary boundary layer PBL for several days thereafter. The ash plume was first seen in the ceilometer backscatter profiles at Hohenpeissenberg in about 6—7 km altitude.
Das Buch erfreut sich in Frankreich einer regen Aufmerksamkeit.
A new global real-time Lagrangian diagnostic system for stratosphere-troposphere exchange: evaluation during a balloon sonde campaign in eastern Canada. The STE calculations are performed following the Lagrangian approach proposed in Bourqui using medium-range, high-resolution operational global weather forecasts. Following every weather forecast, trajectories are started from a dense three-dimensional grid covering the globe, and are calculated forward in time for six days of the forecast.
This system provides daily global STE forecasts that can be used to guide field campaigns, among other applications. The archived data set offers unique high-resolution information on transport across the tropopause for both extra-tropical hemispheres and the tropics. This will be useful for improving our understanding of STE globally, and as a reference for the evaluation of lower-resolution models.
This new data set is evaluated here against measurements taken during a balloon sonde campaign with daily launches from three stations in eastern Canada Montreal, Egbert, and Walsingham for the period 12 July to 4 August An objective identification algorithm developed for this study is used to identify layers in the balloon- sonde profiles affected by stratospheric air and to evaluate the Lagrangian STE forecasts. We find that the predictive skill for the overall intrusion depth is very good for intrusions penetrating down to and hPa, while it becomes negligible for intrusions penetrating below hPa.
Related Tétralogie Ma chère Louisiane (French Edition)
Copyright 2019 - All Right Reserved