SODAR-based estimation of TKE and momentum flux profiles in the atmospheric boundary layer: Test of a parameterization model

Summary A simple parameterization for the estimation of turbulent kinetic energy (TKE) and momentum flux profiles under near-neutral stratification based on sodar measurements of the vertical velocity variance has been tested using data from the LINEX-2000 experiment. Measurements included operation of a phased-array Doppler sodar DSDPA.90 and of a sonic anemometer USA-1 mounted at a meteorological tower at a height of 90m. Good agreement has been found between the TKE and momentum flux values derived from the sonic and sodar data (with correlation coefficients r>0.90 and a slope of the regression lines of about 1.01.1) suggesting the possible use of sodar measurements of _w ² to derive turbulence parameter profiles above the tower range.     

Variations in <Emphasis Type="Italic">foF</Emphasis>2 and <Emphasis Type="Italic">hmF</Emphasis>2 at the end of the 1990s and the beginning of the 2000s

This article considers sparse available data on variations in the main parameters of the ionospheric F2 layer foF2(ss + 2) and hmF2(ss + 2) at the end of the 1990s and the beginning of 2000s. It is shown that the monotonous behavior of hmF2(ss + 2) obtained in earlier publications for the period after 1980 is violated. The hmF2(ss + 2) behavior obtains a more complicated nature by time with a tendency towards a decrease in hmF2(ss + 2) at the beginning of a new century. A statistically significant relationship between foF2(ss + 2) and hmF2(ss + 2) is discovered confirming the Rishbeth statement that during the first hours after sunset, the critical frequency foF2 is governed by dynamical processes via changes in the F2-layer height. It is found that at the end of the interval in question, there is a tendency towards deviations from the above-mentioned dependence. The latter could be a manifestation of the fact that changes in the aeronomical parameters caused by the general cooling and contraction of the thermosphere begin influencing the foF2 value. It is found that in the summer months, the foF2(ss + 2) value demonstrated a systematic decline tendency from the “boundary date” towards the beginning of the 2000s.     

PALEOMAGIA: A PHP/MYSQL database of the Precambrian paleomagnetic data

Most paleomagnetic applications require a precise, rationally organized and up-todate catalogue or database of paleomagnetic results worldwide. These include reconstructions of continents, calculations of the Apparent Polar Wander Paths (APWPs) or paleolatitude drift curves, testing the Geocentric Axial Dipole (GAD) model, studies of geomagnetic paleosecular variation or reversal asymmetries, comparison of coeval results obtained from different types of rocks, estimation of inclination shallowing in sedimentary rocks and understanding the delay in remanence acquisition caused by slow cooling in large intrusions. For this purpose, various databases, such as the Global Paleomagnetic Database (GPMDB), and the Magnetics Information Consortium Database (MagIC) have been generated. This paper presents a new relational database (PALEOMAGIA) where 3278 entries of Precambrian data have been split geographically, sorted according to age and rock types and ranked using a revised version of the Van der Voo grading scheme. The latest geochronologic information is included wherever available. Significant effort has been put to the retrieval and archiving of data published in the last decade, which are virtually nonexistent in GPMDB. Here we present the database and its browser-based user interface from a scientific and a technical point of view.     

About the Role of Quinones in the Action of Some Polyphenols on the Streaming of Protoplasm in Nitella sp. Cells

The concentration of phenols and quinones which stopped the protoplasmic movement in the Nitella cells after 15 min was determined. The quinones (β-naphthoquinone, α-naphthoquinone, p-benzoquinone, o-toluquinone, o-bromanil) stopped the protoplasmic movement in the concentration of (1 3) 10^?4 M, phenols (m-cresol, p-cresol, hydroquinone, guaiacol, phenol, gallic acid, pyrogallic acid, resorcinol) in the concentration of (0.2 5) 10^?2 M, except catechol – 2 10^?3 M. Very high toxicity of catechol and in the prolonged experiments (3 hours) also of hydroquinone is connected with the action of quinonoid productions of its oxidation. This suggestion is confirmed by the experiments:

• – by adding the phenol solutions to Nitella shoots (catechol, hydroquinone, resorcinol) we observed the greatest increase of oxygen absorption in case of catechol (86%), less in case of hydroquinone (38%), and for resorcinol oxygen absorption practically remained on the control level;
• – the action of catechol, hydroquinone and p-benzoquinone did not take place in the presence of glutathione and cysteine (but not cystine and oxidated glutathione);
• – diethyldithiocarbamate as an inhibitor of o-diphenoloxidase reduced the ability of catechol solutions to stop the protoplasmic movement;
• – the low concentrations of benzoquinones were able to stop the protoplasmic movement;
• – for stopping the protoplasmic movement under the prolonged time of incubation from 15 min to 3 hours there was necessary a lower concentration of solutions of hydroquinone and catechol in comparison with resorcinol.

     

Surface wave propagation in a transversely isotropic elastic layer overlying a liquid saturated porous solid half-space and lying under the uniform layer of liquid

Dispersion of Rayleigh-type surface wave is studied in a homogeneous transversely isotropic elastic layer overlying a nondissipative liquid-saturated porous solid half-space and lying under a uniform layer of homogeneous liquid. The frequency equation in the form of ninth-order determinant is obtained.Special cases have been deduced by reducing the depth of the layers to zero and by changing the transverse isotropic layer to an isotropic layer. Dispersion curves for the phase velocity have been plotted for a particular model.     

Use of composite data sets for source-tracking enterococci in the water column and shoreline interstitial waters on Pensacola Beach, Florida

Sources of Enterococcus faecalis isolates from Pensacola Beach, FL. were identified using a library-based approach by applying the statistical method of average similarity to single and composite data sets generated from separate analyses. Data sets included antibiotic resistance analysis (ARA), rep-fingerprints, and fatty acid methyl ester (FAME) profiles. Use of a composite data set composed of ARA and rep-fingerprints, added to the confidence of the identifications. The addition of FAME data to composite data sets did not add to the confidence of identifications. Source identification was performed to better understand risk associated with higher densities of enterococci found in swash zone interstitial water (SZIW) as compared to adjacent bathing water on Pensacola Beach, FL. The "swash zone" is that area of the beach continually washed over by waves. As the potential sources of enterococci were limited in this environment, only two library units, sea gull and human, were constructed. Identification of the beach isolates using a composite data set indicated a sea gull origin. The clonality of the beach isolates suggested that the beach environment selects certain subspecies of E. faecalis.     

On the Measurement of Dewfall and Fog-Droplet Deposition

An observational study has been conducted concerning atmospheric dewfall and fog-droplet deposition with application to the formation and maintenance of fog layers. The relationship between dew and fog is discussed together with the challenges and requirements to measure representative values of their deposition to the surface. A practical instrument developed at the UK Met Office Research Unit, Cardington, is described. The instrument is a small portable device that uses a load cell to measure the weight of a pan upon which various types of natural and artificial canopies can be placed, and can measure dewfall and fog-droplet deposition to an accuracy of 0.0005 mm. Dewfall results from this device are shown for a selection of nights under varying conditions. On a given night the overriding factor determining the amount of dew deposition appears to be location. Several dewmeter devices were placed at different locations around the 18 ha Cardington field site for various clear nights and it was found that dew amounts varied significantly, depending on location: canopies with a more open aspect experienced more deposition by up to a factor of two. The results also suggest that the hygroscopic effect of a canopy, whereby water is absorbed into the canopy and topsoil layer before dew formation begins, is also important for the removal of atmospheric water vapour. Results indicate this effect can be of a similar magnitude to dew deposition. Measurements of fog-droplet deposition showed total water deposition rates did not change when thin radiation fog formed. When optically thick adiabatic fog formed, deposition rates were seen to decrease with time or be generally lower than for thinner radiation fog. Further observations are required to establish if the behaviours found are typical for all fogs.