Miracle-dz/UniFAR-FTUs huggingface dataset:
The solar and dynamically induced oscillations in the stratosphere

The temporal and spatial characteristics of short-term fluctuations in the stratosphere are studied using 30 months of ozone, solar UV, and temperature data from the Nimbus 7 solar backscattered ultraviolet (SBUV) and the stratosphere and mesosphere sounder (SAMS) experiments. It is shown that the stratosphere is in a continuous state of oscillation, with periods varying between 3 to 7 weeks. These oscillations are manifestations of dynamically induced perturbations in the winter hemisphere and the 27-day modulation of the solar UV radiation. Dynamically induced oscillations are global in extent and appear to be independent of solar activity. They are strongest at high latitudes during the fall-spring epoch of each hemisphere. When the seasonal differences of the two hemispheres are taken into account, the high-latitude oscillations in each hemisphere show significant negative correlation with lower latitudes which extends far beyond the tropics into the opposite hemisphere. Their phase shows the characteristics of meridional waves with poleward and equatorward propagations above and below 10 mbar, respectively. Both the multiple regression and cross-spectral analyses of ozone, temperature, and solar flux data show the ozone mixing ratio to be much more sensitive to dynamically induced changes in temperature than to changes in solar UV flux. The solar-induced changes in ozone are detectable only under favorable circumstances, that is, at low latitudes during periods of high solar activity. The estimated change in ozone mixing ratio in the upper stratosphere is about 3% over a solar cycle. This is comparable to a temperature-induced change of about 2 K of dynamical origin.
Molecular Perspectives on the Bantu Expansion: A Synthesis

The expansion of Bantu-speaking peoples over large parts of sub-Saharan Africa is still a matter of debate—not only with respect to the propelling force behind it and the route(s) taken, but, also, in terms of the question whether there actually was a demographic expansion of peoples, rather than just a cultural expansion involving the spread of languages and technologies. In this paper, we provide a critical review of the extant linguistic and molecular anthropological data on Africa and discuss the insights they provide concerning the expansion itself as well as the demographic processes involved in it. Contrary to some assumptions by historians and cultural anthropologists, the genetic data speak in favor of an actual movement of peoples during the expansion of the Bantu languages over Africa, rather than a spread through language and culture shift. Furthermore, the molecular data indicate that sociocultural practices such as patrilocality and possibly even polygyny played a role in shaping the genetic diversity of Bantu-speaking peoples. These sociocultural practices might explain why, in Africa, there is a correlation between Y-chromosomal (i.e., paternal) lineages and linguistic affiliation, but not between mtDNA (maternal) lineages and language.
Three dimensional SEG/EAEG models; an update

This report updates the status of the 3-D SEG/EAEG Modeling Project (SEM). Previous updates appeared in TLE in February 1994, October 1994, and February 1995. The goal is to design two 3-D models, salt and overthrust, and simulate realistic 3-D surveys through numerical calculations.
Geocryological processes linked to High Arctic proglacial stream suspended sediment dynamics: examples from Bylot Island, Nunavut, and Spitsbergen, Svalbard

Recent research has identified differences in processes contributing to suspended sediment concentration (SSC) dynamics in proglacial streams between High Arctic and alpine catchments, but does not examine processes explicitly linked to the periglacial environment. Three glacierized basins were studied: Austre Brøggerbreen and Midre Lovénbreen, Svalbard (79°N, 12°E) and Glacier B28, unofficially named Stagnation Glacier, Bylot Island, Nunavut (73°N, 78°W). SSC variations were modelled from continuous turbidity, discharge and meteorological data throughout the summer months. Three statistical tools were utilized: principal component analysis, change‐point analysis and multivariate regression. These are shown to be effective in identifying subperiods of distinctive geocryological and glaciofluvial characteristics. Multivariate regression for the subseasons included autoregressive integrated moving‐average modelling, and showed that SSC variations were related not only to discharge variability, but also to fluctuations in energy fluxes. The results are interpreted in terms of spatio‐temporal changes in sediment mobilization and supply associated with changes in the relative importance of fluvial, glacial and periglacial processes. This evidence supports the notion of important linkages between glacial, fluvial and periglacial systems, but exemplifies distinct variability between High Arctic glaciers. Copyright © 2005 John Wiley & Sons, Ltd.
Respiration of the belowground parts of vascular plants: its contribution to total soil respiration on a successional glacier foreland in Ny‐Ålesund, Svalbard

As a part of the study on soil carbon flow in a deglaciated area in Ny-Alesund, Svalbard (79°N), we estimated the contribution of the belowground respiration of vascular plants to total soil respiration in August 1996. Four study sites were set up along a primary successional series, ranging from newly deglaciated moraine to older moraine with well-developed vegetation cover. Respiratory activity of the belowground parts (roots + belowground stems) of three dominant species, Salix polaris, Saxifraga oppositifolia and Luzula confusa, was determined under laboratory conditions. The respiratory activity and the Q10 value of the respiration were higher in S. polaris than in the other two species. Total soil respiration rates measured in the field varied widely. The areas with dense vegetation cover tended to show high respiration rates. Belowground respiration of vascular plants was estimated based on the respiratory activity and biomass of the belowground parts at each study site. The contribution to the belowground respiration to total soil respiration was negligible in the early stages of succession. On the other hand, the respiration of the belowground parts contributed to a significant proportion (? 29%) of the total soil respiration in the latter stages of succession.
Relationship between air‐sea gas transfer and short wind waves

Laboratory studies have been conducted in two circular wind wave flumes to investigate the relationship between air-sea transfer velocities of weakly soluble, nonreactive gases and wind-generated surface waves over clean water surfaces and in the presence of surface films. Detailed surface wave measurements have been made using a scanning laser slope gauge. In the circular tanks, longer gravity waves (wavenumber below 12 rad/m) are hardly affected by surfactant, while shorter waves (above 100 rad/m) are significantly reduced. With higher surfactant concentrations, waves above 200–300 rad/m may be completely eliminated. Because of the absence of narrow-banded fetch-limited gravity waves, the wave fields in the circular tanks are significantly different from those in linear wind wave flumes. At a given wind friction velocity, the transfer velocity may decrease by as much as 60% because of surface films. Regardless of the surfactant concentrations, the transfer velocity shows a reasonable correlation with the total mean square slope and with the mean square slope of shorter wind waves (wavenumber above 200 rad/m). However, it shows a poor correlation with the mean square slope of longer wind waves (wavenumber below 50 rad/m). These observations suggest that short wind waves play an important role in air-sea gas exchange.
Effects of lime on pasture production on soils in the North Island of New Zealand 5. Description of a lime recommendation scheme

Abstract A lime recommendation scheme for established pastures on mineral soils is described. The scheme is based on a simple model, using soil pH, to estimate the size of pasture responses to lime at 3 rates of application (1.25, 2.5, and 5.0 t/ha). The estimated pasture production responses to lime are converted to increases in animal production, from which the potential economic benefits of liming are calculated. The limitations and accuracy of the model are discussed. The importance of liming relative to fertiliser nutrient inputs is also discussed and, in particular, it is concluded that lime and fertiliser inputs should be assessed independently. Recommendations for the use of lime on organic soils are also presented.
Comparative Foliar Analysis of Young Balsam Fir Fertilized With Nitrogen, Phosphorus, Potassium, and Lime1

Foliar analyses of individually fertilized balsam fir trees [Abies balsamea (L.) Mill. ] were examined to explain significant growth responses and nutrient status changes. Treatments consisted of factorial combinations of N, P, and K, and one separate treatment of dolomitic lime. Simultaneous comparisons of first year changes in foliar nutrient concentration, content, and dry weight simplified assessment of deficiency, dilution, and luxury consumption. N fertilization increased both needle dry weight and N composition, but lowered foliar P, K, Ca, and Mg concentrations by dilution. Additions of P and/or K did not change needle weight and led to luxury consumption of P and K. Lime alone had no measurable effect in the first year. Overall correlations between foliar concentration and content of individual nutrients accounted for 68-78% of the total variability for foliar P, K, Ca, and Mg, but 99% for foliar N which was unaffected by dilution. A concentration of 2.1-2.3% N in current foliage is the approximate upper limit for growth response for these balsam fir trees. Additional Index Words: Abies balsamea, critical nutrient levels, fertilizer response predictor, limiting nutrient. View complete article To view this complete article, insert Disc 4 then click button8
ESTIMATED CONSUMPTIVE LOSS FROM MAN‐MADE SNOW1

: Consumptive loss of water attributable to man-made snowmaking was estimated using an energy balance model and a mass balance procedure. Data from nine field experiments at Colorado ski areas were collected and used in these models. The mean consumptive loss using the energy balance model for the nine experiments was 6.0 percent and 5.8 percent for the mass balance model A thermodynamic relationship and a regression equation were developed to provide a procedure to estimate consumptive loss as a linear function of atmospheric temperature.
On the ocean salinity stratification observed at the eastern edge of the equatorial Pacific warm pool

[1] The observations collected during a series of three oceanographic cruises dedicated to the study of the frontal zone at the eastern edge of the equatorial Pacific warm pool are used to study the role of salinity in the static stratification of the ocean upper layers. By combining physical and biogeochemical data, the position of the frontal zone at the surface could be accurately determined between 157.5°E and 173.4°E. A multiparameter approach is required due to the uncertainty that may result when one parameter is only considered. In the subsurface the thermohaline structures around the frontal zone reveal the predominant role of the ocean salinity stratification within the isothermal layers. However, the actual methods to determine the salinity barrier layer thickness cannot separate in detail the different dynamical regimes near the frontal zone and another variable to identify the role of the salinity in the static vertical stratification is then proposed and tested on several data sets. This method takes into account the thermal and the saline dependencies in the Brunt-Vaisala frequency in order to isolate the specific role of the salinity stratification in the layers above the main thermocline. The results show that the equatorial western Pacific is characterized by an increasing east-west gradient in salinity stratification whereas the stronger values are found westward of the eastern edge of the warm pool. This diagnostic then provides the basis for an examination of the dynamical mechanisms involved in the formation of the salinity stratification. It also confirms the importance of the ocean salinity in the variability of the equatorial Pacific warm pool. The potentially important implications for the El Nino-Southern Oscillation variability are discussed.
Multiplexed illumination for scene recovery in the presence of global illumination

Global illumination effects such as inter-reflections and subsurface scattering result in systematic, and often significant errors in scene recovery using active illumination. Recently, it was shown that the direct and global components could be separated efficiently for a scene illuminated with a single light source. In this paper, we study the problem of direct-global separation for multiple light sources. We derive a theoretical lower bound for the number of required images, and propose a multiplexed illumination scheme which achieves this lower bound. We analyze the signal-to-noise ratio (SNR) characteristics of the proposed illumination multiplexing method in the context of direct-global separation. We apply our method to several scene recovery techniques requiring multiple light sources, including shape from shading, structured light 3D scanning, photometric stereo, and reflectance estimation. Both simulation and experimental results show that the proposed method can accurately recover scene information with fewer images compared to sequentially separating direct-global components for each light source.
Active fragmentation of Adria, the north African promontory, central Mediterranean orogen

Global Positioning System (GPS) velocities indicate that Adria no longer behaves as a rigid tectonic indenter into southern Europe and is divided into northwestern and southeastern velocity domains. Differential motions are recognized in a velocity field determined from the Peri-Tyrrhenian Geodetic Array (PTGA) and International GPS Service (IGS) sites in the circum-Tyrrhenian region of the central Mediterranean and published GPS velocities from the eastern Adriatic coast. In a fixed Eurasian reference frame, PTGA and IGS site velocities in Sicily and southern Italy are as much as 10 mm/yr in a northward direction, similar to GPS velocities along the eastern coast of the Adriatic Sea. In contrast, velocities in northern Italy are small or statistically insignificant and similar to velocities in Sardinia and Corsica outboard of western Adria. The tectonic boundary dividing Adria is seismically active and passes around the southern and eastern margins of the Tyrrhenian Basin, crosses central Italy, extends into the Adriatic Sea, and follows the western margin of the Dinaride tectonic belt north to the Gulf of Venice. The eastern margin of Adria is approximately located and follows the axis of the central Dinaric Alps southeast to the Hellenic arc. Southeastern Adria has a velocity related to northward motion of Africa, whereas northwestern Adria has negligible differential motion in the Eurasian frame and now is part of the Alpine collage of southern Europe.
Possible Impact of the Indian Ocean SST on the Northern Hemisphere Circulation during El Niño

Abstract Two atmospheric general circulation models (AGCMs), differing in numerics and physical parameterizations, are employed to test the hypothesis that El Nino–induced sea surface temperature (SST) anomalies in the tropical Indian Ocean impact considerably the Northern Hemisphere extratropical circulation anomalies during boreal winter [January–March +1 (JFM +1)] of El Nino years. The hypothesis grew out of recent findings that ocean dynamics influence SST variations over the southwest Indian Ocean (SWIO), and these in turn impact local precipitation. A set of ensemble simulations with the AGCMs was carried out to assess the combined and individual effects of tropical Pacific and Indian Ocean SST anomalies on the extratropical circulation. To elucidate the dynamics responsible for the teleconnection, solutions were sought from a linear version of one of the AGCMs. Both AGCMs demonstrate that the observed precipitation anomalies over the SWIO are determined by local SST anomalies. Analysis of the circu.
A 130 0-year history of vegetation and environmental change at Jan Lake, east-central Alaska

Pollen, stomates and macrofossils were analysed from a 3.63 m sediment core at Jan Lake, eastcentral Alaska, in order to improve spatial resolution of patterns of vegetation history in this region. The chronology was based on 19 AMS 14C dates on plant macrofossils and concentrated pollen. Zone Jan-I (12400-11 600 yr BP) records a unique herb-tundra pollen assemblage, particularly high in Chenopodia ceae, adding supporting evidence for a spatial mosaic of lateglacial vegetation in east-central Alaska. Unexpected pollen of Picea, Betula and Alnus in lateglacial sediments appears to arise from reworking of older pollen-bearing deposits, according to a radiocarbon date of 22180yr BP on a pollen sample. Shrub Betula tundra dominates zone Jan-Il (11 600-10000 yr BP), with indications of climatic amelioration. Tree species (Populus, Picea glauca, Betula papyrifera) began to arrive in zone Jan-Illa (9200-6600 yr BP), and the modern boreal forest, including Alnus and Picea mariana, became established during zone Jan-IIlb (6600-0 yr BP). Fossil stomates appear to be an effective indicator of initial local occurrence of Picea at Jan Lake. Picea arrival at Jan Lake is within 300 years of its arrival at other AMS-dated sites across eastern and central Alaska. A migration route into Alaska through the drainages of the Tanana or Yukon Rivers is hypothesized. Evidence is found for a slight mid-Holocene Picea decline at Jan Lake, intermediate in magnitude between Picea pollen records showing no decline to the east and a larger decline to the west in Alaska.
Precipitation variability and its relationship to hydrologic variability in Alberta

By applying wavelet‐based empirical orthogonal function (WEOF) analysis to gridded precipitation (P) and empirical orthogonal function (EOF) analysis to gridded air temperature (T), potential evapotranspiration (PET), net precipitation (P‐PET) and runoff (Q), this paper examines the spatial, temporal and frequency patterns of Alberta's climate variability. It was found that only WEOF‐based precipitation patterns, possibly modulated by El Nino Southern Oscillation (ENSO) and Pacific Decadal Oscillation(PDO), delineated Alberta into four major regions which geographically represent northern Alberta Boreal forests, southern Alberta grasslands and Aspen Parklands and the Rocky Mountains and Foothills. The leading mode of wavelet‐based precipitation variability WPC1 showed that between 1900 and 2000, a wet climate dominated northern Alberta with significant 4–8, 11 and 25‐year periodic cycles, while the second mode WPC2 showed that between 1960 and 2000, southern Alberta grasslands were characterized by decreasing precipitation, dominated by 11‐year cycles, and the last two modes WPC3 and WPC4 were characterized by 4–7 and 25‐year cycles and both delineated regions where moisture from the Pacific Ocean penetrated the Rocky Mountains, accounted for much of the sub‐alpine climate. These results show that WEOF is superior to EOF in delineating Alberta precipitation variability to sub‐regions that more closely agree with its eco‐climate regions. Further, it was found that while WPC2 could not explain runoff variations in southern Alberta, WPC1, WPC3 and WPC4 accounted for runoff variability in their respective sub‐regions. Copyright © 2009 John Wiley & Sons, Ltd.
Late Proterozoic outer shelf manganese and iron deposits at Otjosondu (Namibia) related to the Damaran oceanic opening

The Otjosondu manganese mining area is located at the eastern exposed extent of the inland branch of the late Proterozoic Damara orogen. In spite of intense deformation and a high-grade metamorphic overprint, the sedimentological interpretation of the manganeserich rocks and their associated lithologies has led to a paleoenvironmental model which gives insight into ore genesis. At least two manganese silicate ore horizons (manganese formations) are associated with banded iron-formations. This sequence is sandwiched between supermature metaquartzarenites interpreted as a shoreface deposit derived from a cratonic basement and deposited under high-energy conditions.Manganese ore varieties and their country rocks have been classified using their texture, mineralogy, and geochemistry and have thus been interpreted in sedimentological and facies terms. The evaluation of the vertical facies sequences, their lateral distribution and their contact relationships renders a spatial reconstruction of the environmental setting for the manganese ores possible. The development of facies from a near-shore clastic regime to manganese-bearing hemipelagic sediments and ultimately to pelagic manganostones and ironstones reflects a zonation on a marine shelf. The facies evolution indicates transgressive conditions on a large scale onto a tectonically stable but subsiding shelf, starting with the transgressive quartzarenites overlying an unconformity to the pre-Damara basement, followed by chemical sediments of the ore-bearing horizon and overlying carbonates, and ending up with pelitic schists. On a smaller scale both transgressive and regressive conditions prevailed during manganese precipitation. Small-scale sedimentary cycles are interpreted as due to glaciogene-influenced fluctuations of the sea level.The source of manganese and iron is proposed to have been situated in the deeper oceanic parts of the associated basin. Initial spreading in the Khomas sea and the formation of oceanic crust is documented by tholeiitic volcanics and associated base metal orebodies representing more proximal manifestations of the exhalative activity. These base metal sulfide deposits are associated with pyrite-bearing graphitic pelagics and this was the first site to partition iron and other base metals from manganese. Upwelling along the shelf edge was involved and additional separation of Mn and Fe was due to a change in Eh conditions associated with a redox interface intersecting with the outer shelf environment. The evolution of the Khomas sea provided the ore-forming solutions and also initiated the subsidence of the passive shelf margin. Fluctuations in sea level were due to the basin development on one hand and glacial-interglacial cycles on the other. The latter fluctuations controlled the amount of terrigenous input into an otherwise pelagic regime.
Ocean modeling for ENSO

Tropical ocean modeling has played a major part in the development of our knowledge of El Nino-Southern Oscillation (ENSO) during the Tropical Ocean-Global Atmosphere (TOGA) decade. Although the foundations had already been laid, it was only with the impetus from TOGA that tropical ocean modeling was able to develop so extensively. In this paper we discuss the development of the wide range of tropical ocean models in use today, from the simple to the complex; the ways in which their abilities to reproduce different phenomena have been assessed; and the ways in which they are being used to better understand and predict the behavior of the coupled ocean-atmosphere system in the tropics. Ocean model development is far from finished, however. Outstanding issues such as forcing fields, model improvements, testing strategies, and applications are also discussed. There is at least as much work to be done in the next decade as was achieved in the last.