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A crucial decision in designing a spatial sample for soil survey is the number of sampling locations required to answer, with sufficient accuracy and precision, the questions posed by decision makers at different levels of geographic aggregation. In the Indian Soil Health Card (SHC) scheme, many thousands of locations are sampled per district. In this paper the SHC data are used to estimate the mean of a soil property within a defined study area, e.g., a district, or the areal fraction of the study area where some condition is satisfied, e.g., exceedence of a critical level. The central question is whether this large sample size is needed for this aim. The sample size required for a given maximum length of a confidence interval can be computed with formulas from classical sampling theory, using a prior estimate of the variance of the property of interest within the study area. Similarly, for the areal fraction a prior estimate of this fraction is required. In practice we are uncertain about these prior estimates, and our uncertainty is not accounted for in classical sample size determination (SSD). This deficiency can be overcome with a Bayesian approach, in which the prior estimate of the variance or areal fraction is replaced by a prior distribution. Once new data from the sample are available, this prior distribution is updated to a posterior distribution using Bayes’ rule. The apparent problem with a Bayesian approach prior to a sampling campaign is that the data are not yet available. This dilemma can be solved by computing, for a given sample size, the predictive distribution of the data, given a prior distribution on the population and design parameter. Thus we do not have a single vector with data values, but a finite or infinite set of possible data vectors. As a consequence, we have as many posterior distribution functions as we have data vectors. This leads to a probability distribution of lengths or coverages of Bayesian credible intervals, from which va

X‐ray photoelectron spectroscopy (XPS) is a widely used surface analysis technique employed in fundamental research, applied research, service laboratories, and industry. Good‐quality analytical outcomes depend critically on spectral references. Many examples of XPS reference databases exist, including print editions, sets of spectral peak positions drawn from the literature, and digital archives and libraries. We report the development of a new digital XPS database comprising survey spectra and region spectra for a range of materials types, collected under a common set of analytical conditions. Each material is described using spectra collected at multiple pass energies with all photoelectron and X‐ray induced Auger transitions represented. Detailed metadata are provided for each material and each spectrum, presented using a schema that incorporates the ISO 16243 and 14976 standards and extensions developed in this work. Spectra are shared under a Creative Commons International (4.0) attribution, non‐commercial licence (CC BY‐NC) in Kratos (.dset), VAMAS (.vms), and XML (.xml) formats. It is intended that reference spectra be imported directly into XPS data analysis software packages for reference and comparison purposes, matching either the peak or transition of interest and the instrument pass energy. The database is flexible and scalable in structure and has the potential to become a core XPS reference resource.

The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.

This paper describes the use of EOS Microwave Limb Sounder (MLS) data to observe the field of traveling planetary waves with quasi 16 day periods. This study utilizes MLS v2.2 temperature and geopotential data between 1 January 2005 and 31 December 2008 in the range 316 hPa to 0.001 hPa (approximately 8 to 97 km) to examine these waves. Analysis demonstrates that the quasi 16 day wavefield is made up of a number of components with westward and eastward propagating s = 1 and s = 2 waves generally dominant. In the Northern Hemisphere the westward and eastward propagating s = 1 waves have similar magnitudes and are larger than the other modes, while in the Southern Hemisphere, the eastward propagating s = 1 and s = 2 waves are larger than the westward propagating wave modes. All of the modes examined display strong seasonal patterns in the temperature amplitude, significant variability in the wave activity from year to year, and the presence of strong pulse-like patterns in the activity. All of the modes also display large median temperature amplitudes poleward of 40 degrees in both hemispheres. Our analysis also demonstrates that the variability in winter from year to year is larger in the Northern Hemisphere than the Southern Hemisphere. Detailed study also suggests that the exclusion of waves from regions of negative refractive index squared likely forms much of the seasonal pattern observed. Thus, regions of strong westward wind speeds effectively exclude vertically propagating waves as expected from theory. The reflection and absorption of waves associated with critical lines is also likely to explain the frequent occurrence of standing wave patterns in the EOS MLS temperature observations. This study highlights the potential of MLS observations for observing waves from the upper troposphere to the lower mesosphere.

Source regions for the westward propagating zonal wavenumber one and three components of the semidiurnal tide observed in the summer mesosphere and lower thermosphere over Antarctica are identified by correlating local tidal variations with global planetary wave one activity in the stratosphere and lower mesosphere. The advantages of using zonal wavenumber resolved tidal amplitudes for such a study are described. The results support the prediction of a source region in the northern hemisphere.

Planetary waves with periods between two and four days in the middle atmosphere over Antarctica are characterized using one year of data from the medium-frequency spaced antenna (MFSA) radars at Scott Base, Rothera, and Davis. In order to investigate the origin of the observed waves, the ground-based data are complemented by temperature measurements from the Earth Observing System Microwave Limb Sounder (EOS MLS) instrument on the Aura satellite as well as wind velocity data from the United Kingdom Met. Office (UKMO) stratospheric assimilation. Observed characteristics of waves with a period of approximately two days in summer are consistent with the quasi-two-day wave (QTDW) generally found after the summer solstice at low- and mid-latitudes. The Scott Base observations of the QTDW presented here are the highest-latitude ground-based observations of this wave to date. Waves with preferred periods of two and four days occur in bursts throughout the winter with maximum activity in June, July, and August. The mean of the two- and four-day wave amplitudes is relatively constant, suggesting constant wave forcing. When several waves with different periods occur at the same time, they often have similar phase velocities, supporting suggestions that they are quasi-non-dispersive. In 2005, a “warmpool” lasts from late July to late August. An alternative interpretation of this phenomenon is the presence of a structure propagating with the background wind. Consideration of the role of vertical shear (baroclinic instabilities) and horizontal shear (barotropic instabilities) of the zonal wind suggests that instabilities are likely to play a role in the forcing of the two- and four-day waves, which are near-resonant modes and thus supported by the atmosphere.

This paper combines four years of radar wind data from Halley and Scott Base in an attempt to resolve the zonal structure of the semi-diurnal tide over Antarctica and to determine the dominant component as a function of time. If only one odd and one even wavenumber component are present then it is possible to calculate the amplitudes and phases of those using data from two stations that are similar in latitude but separated in longitude, ideally by 180. Assuming that the main components of the semi-diurnal tide at Scott Base and Halley latitudes are wavenumber 1 and 2, as has been suggested by other studies, we are able to determine the seasonal variation of both components. The wavenumber 1 component is often dominant in summer, in winter a mixture of wavenumber 1 and 2 is observed. In addition the longitude at which the maxima of the components coincide was determined and found to vary relatively little. Amplitude variations and the longitudes of maxima coincidence were used to investigate the generation mechanisms of the wavenumber 1 wave. Interaction between planetary waves with wavenumber 1 and the wavenumber 2 semi-diurnal tide was found to be a potential mechanism for the generation of the wavenumber 1 component of the tide, confirming theories and observations discussed in the literature. For periods where this explanation for the generation of the wavenumber 1 tide fails we suggest asymmetric heating through solar particle flux as an additional source.

A function that approximates atmospheric tidal behavior in the polar regions is described. This function is fitted to multistation radar measurements of wind in the mesosphere and lower thermosphere with the aim of obtaining a latitude-longitude-height description of the variation of tides over the whole Antarctic continent. Archival wind data sets are combined with present-day ones to fill the spatial distribution of the observations and to reduce the potential effects of spatial aliasing. Multiple years are combined through the compilation of monthly station composite days, yielding results for each month of the year. Despite potential problems associated with year-to-year variations in the tidal phase, a useful climatology of Antarctic zonal and meridional tidal wind components is compiled. The results of the fits reproduce the major features of the high-latitude tidal wind field: the dominance of the semidiurnal migrating mode in the winter months and the presence of a semidiurnal zonal wave number one component in the summer months. It is also found that the summer semidiurnal tide contains a zonal wave number zero component.

Reserves at the New South Wales mine at the end of 1995 were 2 900 000 tonnes grading 0.6% Cu, 0.8% Pb, 0.9% Zn, 7.2 g/t Au and 6 g/t Ag. The ores contain abundant Fe-poor sphalerite with galena, chalcopyrite, pyrrhotite and 2-300 micrometre native gold grains. Production is expanding to 600 000 t in 1997. Longhole open stoping is the primary mining method, with stoping commencing at the keel of the orebody and progressing upwards systematically to avoid the formation of crown pillars. Mined-out stopes are filled with development waste or hydraulic fill, which then provides the base for mucking of broken ore from the stoping lift above. Excess water from the hydraulic fill drains freely through permeable brick bulkheads. Communication from the surface is by telephone or Personal Emergency Device, while a leaky feeder network is being installed., Reserves at the New South Wales mine at the end of 1995 were 2 900 000 tonnes grading 0.6% Cu, 0.8% Pb, 0.9% Zn, 7.2 g/t Au and 6 g/t Ag. The ores contain abundant Fe-poor sphalerite with galena, chalcopyrite, pyrrhotite and 2-300 micrometre native gold grains. Production is expanding to 600 000 t in 1997. Longhole open stoping is the primary mining method, with stoping commencing at the keel of the orebody and progressing upwards systematically to avoid the formation of crown pillars. Mined-out stopes are filled with development waste or hydraulic fill, which then provides the base for mucking of broken ore from the stoping lift above. Excess water from the hydraulic fill drains freely through permeable brick bulkheads. Communication from the surface is by telephone or Personal Emergency Device, while a leaky feeder network is being installed.