DAILY SOLAR RADIATION ESTIMATED FROM TKMPERA TURE RECORDS

Crop growth models and other environmental analyses require the input of daily global solar radiation values. Unfortunately many locations lack long-term solar radiation data. Most agricultural experiment stations, however, have daily temperature records. Also they are often the locations for which crop growth simulations are conducted. In an unpublished manuscript in the field of agricultural meteorology, researchers wanted to address this need. Specifically they wanted to estimate historical daily global solar radiation using daily air temperature data records by adapting a single published empirical intrinsically nonlinear model, a form of the Weibull curve. In order to help future research in the given field, this paper argues that the selected model is a poor choice. Two independent long-term data sets that come from a similar climate to that of the researchers\u27 are used, one for model development and the other for testing model prediction. Through the use of performance statistics on the cross-validation, three alternative models are offeredfor comparison (the performance statistics are accepted by researchers in the agricultural meteorology discipline). The results give no reason to favor the researchers\u27 selected model. Furthermore no model performed well under advective conditions. Future research should consider finding a better means to account for advection, developing and evaluating other models, and justifying the assumptions of the methodology to be employed

AN EXAMPLE OF DEVELOPING COVARIATES FOR PROBLEMS IN PRECISION AGRICULTURE

Methodology for precision agriculture is, perhaps, too focused on methods that allow for spatial correlation in the ANOVA error term. While sound inference about differences between local yields can be computed, no understanding of what is driving these differences is achieved. A completely general form for a spatial model can include suitable covariates. Most research in precision agriculture includes gathering a variety of site-specific information. Through the presentation of the analysis of data from a published soybean [Glycine max (L.) Merr.] study, one specific type of covariate is developed - a duration index for soybean canopy light interception over the growing season. The relationship of the index to grain yield is reasonably well determined (R² = 0.82). We, therefore, suggest that the quest for modeling an appropriate covariate or covariates is primary. Treating spatial variation by other methods should only be used when the quest has failed

SUGGESTIONS FOR PRESENTING KRIGING RESULTS

Kriging maps are often part of the reported analyses in many environmental research studies including those our agency is working on in the area of precision/sustainable farming. All to often important details on the underlying variography and/or kriging procedures are omitted. Likewise the content and form of presenting kriging results vary greatly. Often features of the underlying variability are not readily seen. Instead of reviewing poor practice in current literature, we offer guidelines for reporting the methodology and presenting the results with the use of soil test phosphorus (STP) measures from a real world pasture study. Relevantly, the stationarity assumption for the variogram is argued; computational aspects for both the model and empirical variogram development are reported; and similarly, computational aspects for the kriging surface are reported. In short, enough detail is reported to understand and reproduce the analyses. Standard practice for presenting kriging results should include both the kriging estimates and the associated standard error map. Various planar and three dimensional plots are shown and discussed. Emphasis is on developing quality gray-scale planar maps for conventional publications. Ideally, for both recommended plots, patterns and unique features of the surfaces\u27 variability are revealed

SMAF: A Soil Health Assessment Tool

The Soil Management Assessment Framework (SMAF) was developed to help quantify soil quality/health effects of tillage, crop rotation, and other soil management practices. Our objective was to determine if the SMAF could detect soil health differences after growing a single winter triticale (X Triticosecale Wittmack) crop. Soil samples were collected from 0 to 7.5- and 7.5 to 15- cm depth increments during the 2003 – 2004 and 2004 – 2005 growing seasons near Ames and Lewis, IA, and analyzed for several potential soil quality indicators. The SMAF analysis showed higher soil quality ratings for surface than subsurface samples. It also showed that a single winter grain crop can significantly improve soil quality after either corn (Zea mays L.) or soybean (Glycine max [L.] Merr.). Finally, in response to increasing interest in soil health assessments, a detailed appendix is attached to provide guidance for future soil health assessments

Technical study of a rare Venetian turquoise glass goblet from the Waddesdon Bequest

A Venetian enamelled and gilded goblet (WB.55) is part of the collection bequeathed to the British Museum by Baron Ferdinand Rothschild in 1898. Conservation treatment in 1994 provided the opportunity to remove a small sample containing some opaque white as well as rare turquoise glass. These fragments were analysed using scanning electron microscopy with energy dispersive X-ray spectrometry and by laser ablation inductively coupled plasma mass spectrometry. Further analyses were carried out on the enamels and blue glass knop of the goblet using surface X-ray fluorescence. This contribution locates the object in the context of Venetian glass of the Renaissance as well as the history of collecting. The conservation history and the processes employed to conserve the object prior to its redisplay in the new Waddesdon Gallery at the British Museum in 2015 are described. Careful macroscopic and microscopic observations are combined with the chemical analyses to outline a comprehensive chaîne opératoire for the object. Technically, it is fully consistent with current understanding of glass production in Venice in the late fifteenth century

Bulk Density of a Sandy Loam: Traffic, Tillage, and Irrigation-Method Effects

Modern crop production creates a cycle between soil compaction caused by traffic and alleviation of this condition by tillage or natural processes such as freezing and thawing. The objective of this study was to evaluate important management practices as they relate to changes in bulk density of a tilled sandy loam soil. Practices evaluated were irrigation method, time between tillage and traffic, tire pressure and wheel load of applied traffic, and controlled traffic. Relationships among bulk density, penetration resistance, and infiltration rate were determined. Experiments were conducted in the San Joaquin Valley of California, on a sandy loam soil (Entisol) with an organic-matter content of <1%. After tillage, settling and trafficking of a soil resulted in rapid changes in its bulk density until a new equilibrium was reached. Tire pressure of 408 kPa and wheel weight of 2724 kg applied at moisture contents near field capacity resulted in a bulk density of 1.92 Mg m-3 , compared with a value of 1.67 for no traffic. The time interval between tillage and traffic did not affect final bulk density. Drip irrigation, which did not saturate the soil, resulted in a bulk density of ≈0.1 Mg m-3 lower than flood irrigation, which saturated the soil surface. Wheel traffic in the furrow resulted in only small changes in the bulk density within the row. When tillage did not occur between cropping seasons, traffic caused high bulk densities in the furrow but only small changes in the row. An increase in bulk density from 1.7 to 1.89 Mg m-3 decreased the infiltration rate by four times and increased resistance to penetration at the end of the season by three times. Knowledge of how management practices affect bulk density can aid growers in reducing recompaction following tillage

Errors in Heat Flux Measurement by Flux Plates of Contrasting Design and Thermal Conductivity

The thermal conductivity (λ) of soils may vary by a factor of about 4 for a range of field soil water contents. Measurement of soil heat flux (G) using a heat flux plate with a fixed λ distorts heat flow through the plates and in the adjacent soil. The objectives of this research were to quantify heat flow distortion errors for soil heat flux plates of widely contrasting designs and to evaluate the accuracy of a previously reported correction. Six types of commercially available heat flux plates with varying thickness, face area, and thermal conductivity (λm) were evaluated. Steady-state laboratory experiments at flux densities from 20 to 175 W m−2 were completed in a large box filled with dry or saturated sand having λ of 0.36 and 2.25 W m−1K−1 A field experiment compared G measured with pairs of four plate types buried at 6 cm in a clay soil with G determined using the gradient technique. The flux plates underestimated G in the dry sand by 2.4 to 38.5% and by 13.1 to 73.2% in saturated sand while in moist clay plate performance ranged from a 6.2% overestimate to a 71.4% underestimate. Application of the correction generally improved agreement between plate estimates and independent Gmeasurements, especially when λ \u3e λm, although most plate estimates were still significantly lower than the actual G Limitations of the correction procedure indicate that renewed effort should be placed on innovative sensor designs that avoid or minimize heat flow distortion and/or provide direct, in situ calibration capability

Maintaining Personal Resiliency: Lessons Learned from Evangelical Protestant Clergy

Despite the prominence of clergy in providing human services, and the work-related stressors they experience, clergy health and coping responses have rarely been the focus of psychological research. We report two studies. In the first, we evaluated responses of 398 senior pastors to three open-ended questions regarding personal coping, structural support for their work, and remediation efforts in times of distress. In the second study, Christian mental health professionals and Christian education professionals identified Protestant Christian clergy who exemplify emotional and spiritual health. Twenty-six participated in individual 30-minute interviews. Respondents emphasized the importance of being intentional in maintaining balance in life and developing healthy relationships. They also value a vital spiritual life, emphasizing both their sense of calling into ministry the importance of spiritual disciplines, and an ongoing awareness of God's grace. We suggest ways that Christian mental health professionals can support pastors in preventive and remedial roles. </jats:p

Latitudinal wave coupling of the stratosphere and mesosphere during the major stratospheric warming in 2003/2004

The coupling of the dynamical regimes in the high- and low-latitude stratosphere and mesosphere during the major SSW in the Arctic winter of 2003/2004 has been studied. The UKMO zonal wind data were used to explore the latitudinal coupling in the stratosphere, while the coupling in the mesosphere was investigated by neutral wind measurements from eleven radars situated at high, high-middle and tropical latitudes. It was found that the inverse relationship between the variability of the zonal mean flows at high- and low-latitude stratosphere related to the SSW is produced by global-scale zonally symmetric waves. Their origin and other main features have been investigated in detail. Similar latitudinal dynamical coupling has been found for the mesosphere as well. Indirect evidence for the presence of zonally symmetric waves in the mesosphere has been found

Wave activity (planetary, tidal) throughout the middle atmosphere (20-100km) over the CUJO network: Satellite (TOMS) and Medium Frequency (MF) radar observations

Planetary and tidal wave activity in the tropopause-lower stratosphere and mesosphere-lower thermosphere (MLT) is studied using combinations of ground-based (GB) and satellite instruments (2000-2002). The relatively new MFR (medium frequency radar) at Platteville (40&amp;deg; N, 105&amp;deg; W) has provided the opportunity to create an operational network of middle-latitude MFRs, stretching from 81&amp;deg; W-142&amp;deg; E, which provides winds and tides 70-100km. CUJO (Canada U.S. Japan Opportunity) comprises systems at London (43&amp;deg; N, 81&amp;deg; W), Platteville (40&amp;deg; N, 105&amp;deg; W), Saskatoon (52&amp;deg; N, 107&amp;deg; W), Wakkanai (45&amp;deg; N, 142&amp;deg; E) and Yamagawa (31&amp;deg; N, 131&amp;deg; E). It offers a significant 7000-km longitudinal sector in the North American-Pacific region, and a useful range of latitudes (12-14&amp;deg;) at two longitudes. Satellite data mainly involve the daily values of the total ozone column measured by the Earth Probe (EP) TOMS (Total Ozone Mapping Spectrometer) and provide a measure of tropopause-lower stratospheric planetary wave activity, as well as ozone variability. &lt;P style=&quot;line-height: 20px;&quot;&gt; Climatologies of ozone and winds/tides involving frequency versus time (wavelet) contour plots for periods from 2-d to 30-d and the interval from mid 2000 to 2002, show that the changes with altitude, longitude and latitude are very significant and distinctive. Geometric-mean wavelets for the region of the 40&amp;deg; N MFRs demonstrate occasions during the autumn, winter and spring months when there are similarities in the spectral features of the lower atmosphere and at mesopause (85km) heights. Both direct planetary wave (PW) propagation into the MLT, nonlinear PW-tide interactions, and disturbances in MLT tides associated with fluctuations in the ozone forcing are considered to be possible coupling processes. The complex horizontal wave numbers of the longer period oscillations are provided in frequency contour plots for the TOMS satellite data to demonstrate the differences between lower atmospheric and MLT wave motions and their directions of propagation