Average Departures Research Articles

Dual carbonate clumped isotope (Δ47-Δ48) measurements constrain different sources of kinetic isotope effects and quasi-equilibrium signatures in cave carbonates

Cave carbonate minerals are an important terrestrial paleoclimate archive. A few studies have explored the potential for applying carbonate clumped isotope thermometry to speleothems as a tool for constraining past temperatures. To date, most papers utilizing this method have focused on mass-47 clumped isotope values (Δ47) at a single location and reported that cave carbonate minerals rarely achieve isotopic equilibrium, with kinetic isotope effects (KIEs) attributed to CO2 degassing. More recently, studies have shown that mass-47 and mass-48 CO2 from acid digested carbonate minerals (Δ47 and Δ48) can be used together to assess equilibrium and probe KIEs. Here, we examined 44 natural and synthetic modern cave carbonate mineral samples from 13 localities with varying environmental conditions (ventilation, water level, pCO2, temperature) for (dis)equilibrium using Δ47-Δ48 values, in concert with traditional stable carbon (δ13C) and oxygen (δ18O) isotope ratios. Data showed that 19 of 44 samples exhibited Δ47-Δ48 values indistinguishable from isotopic equilibrium, and 18 (95 %) of these samples yield Δ47-predicted temperatures within error of measured modern temperatures. Conversely, 25 samples exhibited isotopic disequilibria, 13 of which yield erroneous temperature estimates. Within some speleothem samples, we find Δ47-Δ48 values consistent with CO2 degassing effects, however, the majority of samples with KIEs are consistent with other processes being dominant. We hypothesize that these values reflect isotopic buffering effects on clumped isotopes that can be considerable and cannot be overlooked. Using a Raleigh Distillation Model, we examined carbon and oxygen isotope exchange trajectories and their relationships with dual clumped isotope disequilibria. Carbon isotope exchange is associated with depletion of both Δ47 and Δ48 relative to equilibrium, while oxygen isotope exchange is associated with enrichment of both Δ47 and Δ48 relative to equilibrium. Cave rafts collected from proximate locations in Mexico exhibit the largest average departures from equilibrium (ΔΔ47¯ = −0.032 ± 0.007, ΔΔ48¯ = −0.104 ± 0.035, where ΔΔi is the measured value – the equilibrium value). This study shows how the Δ47-Δ48 dual carbonate clumped isotope framework can be applied to a variety of tcave carbonate mineral samples, enabling identification of isotopic equilibria and therefore quantitative application of clumped isotope thermometry for paleoclimate reconstruction, or alternatively, constraining the mechanisms of kinetic effects.

EVALUASI KINERJA OPERASIONAL TERMINAL DARA KOTA BIMA

Terminal Dara is the center of community activities in meeting the needs for movement from one place to another with various purposes used by the people of the of Bima City and Regency. Terminal Dara has experienced a decline and an increase in the number of transportation from year to year; this condition makes facilities and operational performance at the Dara Terminal become very important. The purpose of this study is to determine the operational performance and facilities as well as the current area of Dara Terminal facilities. The method used in this study is a direct survey in the field for primary data by recording the bus license plate, time of entry and exit of buses and visitors vehicles at the entrance and exit gate and recording the number of passengers and users of waiting rooms, the number of seats in passenger waiting rooms, and bus station facilities. Data collection is carried out for three days with duration of 13 hours each day.Based on the results of the analysis of the performance that has been carried out, the value for the bus queue analysis ρ = 2.11> 1 indicates that there is a queue of bus services at Dara bus station. The highest value of arrival average time headway is 17 minutes 22 seconds and the departures average time headway is 12 minutes 23 seconds. The highest departure load factor is 81.44% in the ANGDES and the highest load factor is 73.64% in ANGDES too. The parking space requirement for cars and motorbikes of 128 m² can still be served by vehicle parking area in bus station, while the parking area for bus is not able to serve bus which parked in the bus parking area with the value of parking space needs 902.5 m² while the area the current bus parking area is 631.25 m². Based on the results of the performance analysis that has been done, the value obtained for bus queue analysis ρ = 2.11> 1 indicates that there is a queue of bus services in Dara Terminal. The time between the highest average arrivals is 17 minutes 22 seconds and the time between the highest average departures is 12 minutes 23 seconds. The highest departure load factor was 81.44% at ANGDES and the highest arrival load factor was 73.64% at ANGDES as well. The need for parking spaces for private cars and motorbikes of 128 m² can still be served by the terminal private vehicle parking area, while the parking area for buses is not able to serve buses that park in the bus parking area with a value of 902.5 m² of parking space while the area the bus parking area is currently 631.25 m². Based on existing survey results, the bus departure lane and passenger lounge of Terminal Daral need to be renovated, or they can relocate the terminal to a wider area.

CLASSIFICATION OF COUNTRIES OF ORIGIN OF TOURISTS BY GROSS AND PER CAPITA INDICATORS OF OUTBOUND TOURISM

Problem Statement and Purpose. According to the World Tourism Organization (UNWTO). about 1 billion international tourists were recorded in the world at the turn of the millennium. At the same time, the countries of the world were differently involved in the formation of such flows, so half of them belonged to the European region. The purpose of the study is the classification of countries of origin of tourists by the number of outbound departures: gross and per 100 residents, including taking into account cost indicators, in particular, the tourist expenditures per departure.Data «£ Methods. The study is based on the World Bank's statistical base and the methodology of the World Tourism Organization (UNWTO). In particular, the international (outbound) tourism is estimated in natural (departures) and value (expenditures) indicators proposed by the UNWTO. For consideration of these indicators by countries, a method statistics was used on the statistical base of the World Bank.Results. As a result of the comparison of gross and specific (per 100 residents) the number of outbound tourist departures for 87 countries of the world in 2008, the classification of countries of origin of tourists was carried out. The criteria for classification were the average arithmetic gross departures, which for the sample amounted to about 10 million, and for specific indicators - the proportion of tourists in the country's population, with that tourism is considered mass, that is. when traveling more than 50%. Thus, by the total number of departures, the country of origin of tourists was divided into small and large, and by the specific - intensive and extensive outbound tourism, and taking into account the tourist expenditures per one departure, they are still divided into countries of inexpensive and expensive outbound tourism.

Seasonal prediction of summer monsoon rainfall over cluster regions of India

Shared nearest neighbour (SNN) cluster algorithm has been applied to seasonal (June–September) rainfall departures over 30 sub-divisions of India to identify the contiguous homogeneous cluster regions over India. Five cluster regions are identified. Rainfall departure series for these cluster regions are prepared by area weighted average rainfall departures over respective sub-divisions in each cluster. The interannual and decadal variability in rainfall departures over five cluster regions is discussed. In order to consider the combined effect of North Atlantic Oscillation (NAO) and Southern Oscillation (SO), an index called effective strength index (ESI) has been defined. It has been observed that the circulation is drastically different in positive and negative phases of ESI-tendency from January to April. Hence, for each phase of ESI-tendency (positive and negative), separate prediction models have been developed for predicting summer monsoon rainfall over identified clusters. The performance of these models have been tested and found to be encouraging.

Intra-City Variation in Urban Morphology and Turbulence Structure in Helsinki, Finland

Most atmospheric boundary-layer theories are developed over vegetative surfaces and their applicability at urban sites is questionable. Here, we study the intra-city variation of turbulence characteristics and the applicability of boundary-layer theory using building-morphology data across Helsinki, and eddy-covariance data from three sites: two in central Helsinki (400 m apart) and one 4 km away from the city centre. The multi-site measurements enable the analysis of the horizontal scales at which quantities that characterize turbulent transport vary: (i) Roughness characteristics vary at a 10-m scale, and morphometric estimation of surface-roughness characteristics is shown to perform better than the often used rule-of-thumb estimates (average departures from the logarithmic wind profile are 14 and 44 %, respectively). (ii) The drag coefficient varies at a 100-m scale, and we provide an updated parametrization of the drag coefficient as a function of z/zH (the ratio of the measurement height to the mean building height). (iii) The transport efficiency of heat, water vapour and CO2 is shown to be weaker the more heterogeneous the site is, in terms of sources and sinks, and strong scalar dissimilarity is observed at all sites. (iv) Atmospheric stability varies markedly even within 4 km across the city: the median difference in nocturnal sensible heat fluxes between the three sites was over 50W m−2. Furthermore, (v) normalized power spectra and cospectra do not vary between sites, and they follow roughly the canonical theory as developed over vegetated terrain.

A respiratory alert model for the Shenandoah Valley, Virginia, USA

Respiratory morbidity (particularly COPD and asthma) can be influenced by short-term weather fluctuations that affect air quality and lung function. We developed a model to evaluate meteorological conditions associated with respiratory hospital admissions in the Shenandoah Valley of Virginia, USA. We generated ensembles of classification trees based on six years of respiratory-related hospital admissions (64,620 cases) and a suite of 83 potential environmental predictor variables. As our goal was to identify short-term weather linkages to high admission periods, the dependent variable was formulated as a binary classification of five-day moving average respiratory admission departures from the seasonal mean value. Accounting for seasonality removed the long-term apparent inverse relationship between temperature and admissions. We generated eight total models specific to the northern and southern portions of the valley for each season. All eight models demonstrate predictive skill (mean odds ratio = 3.635) when evaluated using a randomization procedure. The predictor variables selected by the ensembling algorithm vary across models, and both meteorological and air quality variables are included. In general, the models indicate complex linkages between respiratory health and environmental conditions that may be difficult to identify using more traditional approaches.

Tidal-amplitude rhythms of larval release: variable departure from presumed optimal timing among populations of the mottled shore crab

It is widely assumed that optimal timing of larval release is of major importance to offspring survival, but the extent to which environmental factors entrain synchronous reproductive rhythms in natural populations is not well known. We sampled the broods of ovigerous females of the common shore crab Pachygrapsus transversus at both sheltered and exposed rocky shores interspersed along a 50-km coastline, during four different periods, to better assess inter-population differences of larval release timing and to test for the effect of wave action. Shore-specific patterns were consistent through time. Maximum release fell within 1 day around syzygies on all shores, which matched dates of maximum tidal amplitude. Within this very narrow range, populations at exposed shores anticipated hatching compared to those at sheltered areas, possibly due to mechanical stimulation by wave action. Average departures from syzygial release ranged consistently among shores from 2.4 to 3.3 days, but in this case we found no evidence for the effect of wave exposure. Therefore, processes varying at the scale of a few kilometres affect the precision of semilunar timing and may produce differences in the survival of recently hatched larvae. Understanding the underlying mechanisms causing departures from presumed optimal release timing is thus important for a more comprehensive evaluation of reproductive success of invertebrate populations.

Entropic descriptor of a complex behaviour

We propose a new type of entropic descriptor that is able to quantify the statistical complexity (a measure of complex behaviour) by taking simultaneously into account the average departures of a system’s entropy S from both its maximum possible value S max and its minimum possible value S min . When these two departures are similar to each other, the statistical complexity is maximal. We apply the new concept to the variability, over a range of length scales, of spatial or grey-level pattern arrangements in simple models. The pertinent results confirm the fact that a highly non-trivial, length scale dependence of the entropic descriptor makes it an adequate complexity measure, able to distinguish between structurally distinct configurational macrostates with the same degree of disorder, a feature that makes it a good tool for discerning structures in complex patterns.

Evidence for Changing Flood Risk in New England Since the Late 20th Century1

Abstract: Long‐term flow records for watersheds with minimal human influence have shown trends in recent decades toward increasing streamflow at regional and national scales, especially for low flow quantiles like the annual minimum and annual median flows. Trends for high flow quantiles are less clear, despite recent research showing increased precipitation in the conterminous United States over the last century that has been brought about primarily by an increased frequency and intensity of events in the upper 10th percentile of the daily precipitation distribution – particularly in the Northeast. This study investigates trends in 28 long‐term annual flood series for New England watersheds with dominantly natural streamflow. The flood series are an average of 75 years in length and are continuous through 2006. Twenty‐five series show upward trends via the nonparametric Mann‐Kendall test, 40% (10) of which are statistically significant (p < 0.1). Moreover, an average standardized departures series for 23 of the study gages indicates that increasing flood magnitudes in New England occurred as a step change around 1970. The timing of this is broadly synchronous with a phase change in the low frequency variability of the North Atlantic Oscillation, a prominent upper atmospheric circulation pattern that is known to effect climate variability along the United States east coast. Identifiable hydroclimatic shifts should be considered when the affected flow records are used for flood frequency analyses. Special treatment of the flood series can improve the analyses and provide better estimates of flood magnitudes and frequencies under the prevailing hydroclimatic condition.

Direct measurement of the size, shape, and pole of 511 Davida with Keck AO in a single night

Using the high-quality data set of 165 images taken at 11 epochs over the 5.13 h rotation of the large C-type Asteroid 511 Davida, we find the dimensions of its triaxial ellipsoid model to be 357 ± 2 × 294 ± 2 × 231 ± 50 km . The images were acquired with the adaptive optics system on the 10 m Keck II telescope on December 27, 2002. The a and b diameters are much better determined than previously estimated from speckle interferometry and indirect measurements, and our mean diameter, ( a b c ) 1 / 3 = 289 ± 21 km , is 19% below previous estimates. We find the pole to lie within 2° of [ RA = 295 ° ; Dec = 0 ° ] or in Ecliptic coordinates [ λ = 297 ° ; β = + 21 ° ], a significant improvement to the pole direction. Otherwise, previous determinations of the axial ratios agree with our new results. These observations illustrate that our technique of finding the dimensions and pole of an asteroid from its changing projected size and shape is very powerful because it can be done in essentially one night as opposed to decades of lightcurves. Average departures of 3% (5 km) of the asteroid's mean radius from a smooth outline are detected, with at least two local positive-relief features and at least one flat facet showing approximately 15 km deviations from the reference best-fit ellipsoid. The facet is reminiscent of large global-scale craters on Asteroid 253 Mathilde (also a C-type) when seen edge-on in close-up images from the NEAR mission flyby. We show that giant craters (up to 150 km diameter, the size of the largest facets seen on Davida) can be expected from the impactor size distribution, without likelihood of catastrophic disruption of Davida.

Angular momentum fluctuations within the Earth's liquid core and torsional oscillations of the core-mantle system

Summary Non-steady differential rotation is one of the main characteristics of the buoyancy-driven flow within the Earth's liquid metallic outer core that generates the main geomagnetic field by magnetohydrodynamic (MHD) dynamo action. Concomitant fluctuations in angular momentum transfer both within the core and between the core and the overlying ‘solid’ mantle are investigated by assuming that average departures from ‘isorotation’ on coaxial cylindrical surfaces are negligibly small. The interval of time covered by the analysis is the 15 decades from 1840 to 1990, for which requisite determinations are available of decadal fluctuations of the length of the day (LOD) and also of flow velocities just below the core–mantle boundary (CMB), as inferred from geomagnetic secular variation (GSV) data. Core angular momentum (CAM) fluctuations are most pronounced in the mid-latitudes, where they are generally out of phase with those occurring in equatorial regions. They are roughly in phase with decadal LOD fluctuations, especially after about 1870, with a dominant variability period of approximately 65 years, in keeping with previous analyses based on GSV and/or LOD data. The largest positive correlations (0.8 when data before 1867.5 are excluded) are found in the mid-latitudes, with a maximum at zero lag and with secondary peaks at 67 years and at −64 years, again implying a mode of approximately 65 years. Propagation of CAM anomalies from the equatorial to polar regions is evident in both the time-latitude dependence of CAM and its latitudinal correlation with length of day fluctuations. Future work on excitation mechanisms should establish the connection, if any, between the dominant timescale of approximately 65 years seen in the data and the gravest of the theoretically possible subseismic modes of torsional MHD oscillations of the core.

Nao and sea surface temperature signatures in tree-ring records from the North Atlantic sector

Temperature-sensitive tree-ring chronologies from Scandinavia and Labrador are, respectively, analyzed for their response to two major features of North Atlantic climate variability: (1) the North Atlantic Oscillation (NAO), and (2) Coastal and near-coastal surface air and sea surface temperatures (SSTs). (1) NAO: Using superposed epoch analysis (SEA), below (above) average ring-width departures from Scandinavian scots pine (Pinus sylvestris L.) were found to follow positive (negative) anomalies in winter (December-February) sea level pressure (SLP) related to the Icelandic low pressure cell, a key element of the NAO. In addition to a documented summer temperature relationship, these trees show a positive correlation with winter temperatures for Oslo, Norway. Oslo data are used to define the northwest European end of the winter temperature seesaw, another major feature of the NAO. Below (above) average tree-growth departures tend to follow Greenland Above, GA or (Greenland Below, GB) seesaw winters, which are associated with high (low) pressure and cold (warm) conditions over Scandinavia. (2) SSTs: Growing season (April–September) land/sea temperatures were reconstructed for three 5°×5° gridcells (50–55°N, 50–65°W) near the coast of Labrador for the period from 1813 to 1988. The tree-ring data used in this case were four maximum latewood density chronologies of white spruce (Picea glauca [Moench] Voss) from sites in southern and central Labrador. An alternative model, based on only two chronologies, allows extension of these reconstructions back to 1713. The reconstructions explain about 45% of the temperature variance from 1915–1988 and pass several tests for model validation with high levels of statistical significance. They primarily provide information on short-period (

The Relationship Between Eastern Equatorial Pacific Sea Surface Temperatures and Rainfall over India and Sri Lanka

Abstract Monsoon season (June–September) precipitation data from 31 Indian subdivisions and mean monthly precipitation data from 35 Indian and Sri Lanka stations, spanning the period 1875–79, were analyzed to determine the relationship between equatorial Pacific warm episodes (El Nino events) and interannual fluctuations in precipitation over India and Sri Lanka. The data reveal a strong tendency for a below normal summer monsoon during the 25 moderate/strong warm episodes which occurred during the period. For example, area-averaged June–September rainfall over India was below the median value in 21 of the 25 warm episode years. These years include the five largest, and nine of the eleven largest, negative monsoon season anomalies. Considerably smaller average departures occurred during the monsoon seasons of the year preceding and the year following the warm episode, and during the remaining months of the warm episode year. The anomaly pattern over Sri Lanka and extreme southern India is quite different,...

El Niño and Tropical Pacific Ocean Surface Temperatures

Abstract The spatial and temporal character of El Nino is explored with analyses of tropical Pacific Ocean surface temperatures for the period 1957–76. The data are derived from approximately 5×106 marine weather reports. Maps are illustrated which portray the initiation, maturation and decay of an “average” El Nino event. Empirical orthogonal functions of nonseasonal departures are displayed. The time coefficients of the dominant empirical functions are derived together with average departures for 18 regions which are usually 10° of latitude and 40–50° of longitude in size. Lag correlation and coherence-spectral analysts are carried out on all of the time series. The pattern of El Nino which is portrayed is that of a basinwide phenomenon with a time evolution lasting more than 24 months. During this evolution sea temperatures in the western Pacific tend to have departures of opposite sign to those in the cast. Variations in the eastern equatorial region are shown to precede those in the central equatoria...

Stratospheric temperatures during solar cycle 20

Summertime rocketsonde temperature data for 1965–1977 at seven sites, 8°S‐64°N, were adjusted to reduce previously uncorrected instrumental errors. The data were then carefully processed to yield yearly average temperature departures from the average temperatures for 1965–1977. At two levels, 35 and 50 km, the yearly departures as well as 3‐year moving averages (with 1‐2‐1 weighting) were compared to the mean annual sunspot number, both for individual stations and for the combined station data. The smoothed temperature departures for the combined data show a correlation of +0.89 with sunspot numbers at both altitudes but with greater temperature range (4.5°C) at 35 km. Except for two special circumstances, correlations at individual stations (smoothed data) range from +0.72 to +0.94; the corresponding amount of temperature change from near‐solar maximum (1969) to near‐solar minimum (1975) varies among the stations from −3°C to −6°C. The observed temperature variations during solar cycle 20 are well within recent model calculations that are based on observed fluctuations in solar ultraviolet radiation.

The U. S. Navy Numerical Frontal Analysis Scheme: Further Development and a Limited Evaluation

Abstract Essentials of the U. S. Navy's numerical frontal analysis model, employing special second derivatives of the potential temperature field, are reviewed. The scheme is extended to include frontal-prognosis problems, visual presentation of numerical fronts, and application of the new approach to other areas of interest in meteorology and oceanography. The difficulties of accurately depicting baroclinicity for surface frontal analysis are also discussed. A limited evaluation of the surface, 1000- and 850-mb numerical frontal analyses relative to manually analyzed fronts for six synoptic times in February 1965 over the western part of the Northern Hemisphere is presented. Average departures of numerical frontal positions from U. S. Weather Bureau analyses are about 100 n mi and are less than 50 per cent of the mesh length used by the Fleet Numerical Weather Facility. Merits and deficiencies at each of these three levels are enumerated and discussed.

The Electric Field Intensity and Its Systematic Changes Under an Active Thunderstorm

Reliable induction electric field intensity meters were installed at the four corners of an 8.5 kilometer square. The values of the field intensity were transferred to a base laboratory via telephone lines and applied to a 4 channel oscilograph permitting the simultaneous recording of some 480 lightning discharge events occurring in a single typical active thunderstorm. Two other channels measured the current discharged by a sharp point and the charges on individual raindrops falling at the base laboratory. Negative charges normally accumulated overhead and were transferred out of the clouds in 95% of the lightning discharges. The average electric field at the ground prior to discharge was +21.8 volts cm−1 volts cm100 These values were notably smaller than those measured in 1955 on the Ransas plains. Curves are given for the average initial and final values of the electric field, for the average departures at each station from the network average and for the time varying positions of the approximate centers of free electrical charge. The frequent complete reversal of the normal initial electric field intensity by the lightning discharge is confirmed. The relation of the large negative post-lightning fields to the reverse currents and corona discharge backward through the original discharge channels or branches is considered. It is noted that the negative corona is much larger and more easily visible than the positive corona under the same conditions of voltage and current. Accordingly, frequent reports of post-lightning electrical phenomena are to be anticipated.

Kansas Phytopathological Notes: 1961

Plant disease development under natural field conditions depends on many factors, especially temperature and moisture. Precipitation during the growing season is highly conducive to many diseases, through its great impact on plant pathogen buildup. Even monthly average departures from long-term means of temperature and precipitation correlate well with plant disease occurrence. This information is important to plant pathologists in predicting and forecasting warnings to producers of agricultural commodities. As a result, better and more effective methods can be devised in plant protection. Summarized data of monthly temperature and precipitation departures for Kansas in 1961 are presented in Table 1. Such numerical criteria, although useful in overall analysis, are too crude to explain precisely the conditions favoring the occurrence and development of numerours pathogenic organisms on many different crops during the reported year. A short review of weather conditions will help to clarify the incidence and severity, particularly of soilborne and leaf-spot diseases. January, 1961, was the driest January ever recorded in Kansas, with mild temperatures during the first 3 weeks; but cold later. Well distributed and sufficient precipitation with above average temperatures in February stimulated activities in preparation of soil for spring planting, These were enhanced by warm and uniformly distributed temperatures and adequate and frequent well distributed rains in March in all parts of the state.

GEOSTROPHIC AND GRADIENT DEPARTURES IN JET STREAMS

Abstract Wind measurements made by aircraft of Project Jet Stream during forty-eight flights are compared with geostrophic and gradient winds (computed on upper-air charts) in order to determine geostrophic and gradient departures. Due to random errors in radiosonde data and to a lesser extent in the aircraft winds, individual departures are not reliable. Therefore, the jet stream area, as represented on a vertical cross-section perpendicular to the wind flow, is arbitrarily divided into nine sectors. Average departures are computed for each sector and for certain combinations of sectors. In cyclonic jet streams (i.e., in the vicinity of upper troughs), these calculations gave the following results: observed wind speeds were, on the average, 27.5 kn (or 18.4 per cent) less than geostrophic speeds but were in excellent agreement with gradient speeds. Although the average gradient departure was approximately zero, these departures tended to be negative (observed winds less than gradient winds) on the south ...

Geostrophic Departures in the Jet Stream

The effect of gradients in the cross-current eddy motions on the geostrophic balance is illustrated by means of an integrated model. It is suggested that gradients of the Reynolds stress associated with such eddy motions in the atmosphere and in the oceans may lead to sensible average geostrophic departures which appear as a normal inertial effect in eddying currents. DOI: 10.1111/j.2153-3490.1950.tb00334.x