Miracle-dz/UniFAR-FTUs huggingface dataset:
Spatial representativeness of ground‐based solar radiation measurements

The validation of gridded surface solar radiation (SSR) data often relies on the comparison with ground‐based in situ measurements. This poses the question on how representative a point measurement is for a larger‐scale surrounding. We use high‐resolution (0.03°) SSR data from the Satellite Application Facility on Climate Monitoring (CM SAF) to study the subgrid spatial variability in all‐sky SSR over Europe and the spatial representativeness of 143 surface sites with homogeneous records for their site‐centered larger surroundings varying in size from 0.25° to 3°, as well as with respect to a given standard grid of 1° resolution. These analyses are done on a climatological annual and monthly mean basis over the period 2001–2005. The spatial variability of the CM SAF data set itself agrees very well with surface measurements in Europe, justifying its use for the present study. The annual mean subgrid variability in the 1° standard grid over European land is on average 1.6% (2.4 W m−2), with maximum of up to 10% in Northern Spain. The annual mean representation error of point values at 143 surface sites with respect to their 1° surrounding is on average 2% (3 W m−2). For larger surroundings of 3°, the representation error increases to 3% (4.8 W m−2). The monthly mean representation error at the surface sites with respect to the 1° standard grid is on average 3.7% (4 W m−2). This error is reduced when site‐specific correction factors are applied or when multiple sites are available in the same grid cell, i.e., three more sites reduce the error by 50%.
Basin‐wide warming of the Indian Ocean during El Niño and Indian Ocean dipole years

Basin‐wide wintertime surface warming is observed in the Indian Ocean during El Niño years. The basin‐wide warming is found to be stronger when El Niño and Indian Ocean Dipole (IOD) co‐occur. The mechanisms responsible for the basin‐wide warming are different for the years with El Niño only (El Niño without IOD) and for the co‐occurrence (both El Niño and IOD) years. Strong westward propagation of downwelling Rossby waves is observed in the southern Indian Ocean during the IOD years. Such strong propagation is not seen in the case of the El Niño‐only years. This indicates that the ocean dynamics play an important role in winter warming of the western Indian Ocean during the IOD years. The weak easterly wind anomalies in the El Niño‐only years show no measurable impact on the Wyrtki Jets, but weakening or reversal of these jets is seen in the IOD years. This strongly suggests that the variability related to surface circulation is due to the local IOD forcing rather than El Niño induced wind anomaly. For the El Niño‐only composites, surface heat fluxes (mainly latent heat flux and short wave radiation) play an important role in maintaining the basin‐wide surface warming in the Indian Ocean. In the IOD‐only composites (when there is no El Niño in the Pacific), such basin‐wide warming is not seen because of the absence of ENSO (El Niño and Southern Oscillation) induced subsidence over the eastern Indian Ocean. For the years in which both El Niño in the Pacific and dipole in the Indian Ocean co‐occur, warming in the western Indian Ocean is due to the ocean dynamics and that in the eastern Indian Ocean is due to the anomalous latent heat flux and solar radiation. Copyright © 2007 Royal Meteorological Society
Geochronology and geochemistry of the Dabure basalts, central Qiangtang, Tibet: evidence for ~550 Ma rifting of Gondwana

Newly discovered basalts in the Dabure area (central Qiangtang block, northern Tibet) were subjected to laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb zircon dating, geochemical analyses, and zircon Hf isotope analyses. Dating of magmatic zircons from three basalt samples indicates that the Dabure basalts formed during the late Ediacaran (~550 Ma). Xenocrystic zircons yield ages of 700–1150 Ma, providing evidence of the Cryogenian crust in the Tibet block. The Dabure basalts are alkaline, rich in Ti and Fe, and are strongly enriched in light rare earth elements without Eu anomalies. The basalts are geochemically similar to within-plate basalts but are relatively depleted in Nb and Ta. Although the analysed zircons show differences in their Hf isotope compositions, the geochemical data suggest that the Dabure basalts were derived from enriched mantle and that the source magmas were contaminated by the continental crust. The basalts may have erupted during rifting at ~550 Ma (from the dating of magmatic zircons), and may have been a product of the initial breakup of Gondwanaland.
Relationship between the Tibetan Snow in Spring and the East Asian Summer Monsoon in 2003: A Global and Regional Modeling Study

In 2003, a climate extreme accompanying a wet and cool summer over East Asia was recorded over the East Asian countries including central China, Korea, and Japan. A possible relation of this record-breaking summer in East Asia to above-normal snowfall over the Tibetan Plateau in spring has been investigated using the National Centers for Environmental Prediction (NCEP) global and regional models. The changes in the simulated East Asian summer monsoon circulations in response to snow anomalies over Tibet are highlighted. The results from both global and regional model experiments suggest that above-normal snowfall over the Tibetan Plateau in May induces a weakening of the Tibetan high, which leads to the formation of favorable upper-level circulations accompanying cyclonic circulation anomalies covering the East Asian region in summer. These circulation anomalies inresponse tothe snow anomalies over theplateau aremore robust and closer towhat wasobserved in the regionalthan inthe global model results. The sensitivity experimentsalso show that the precipitation and lower-level circulation anomalies in summer, caused by the snow anomalies in spring, influence the above-normal precipitation in the lower reaches of the Yangtze River basin, as revealed in previous observational studies. However, the experiments do not fully explain the observed signals in Korea and Japan since the spring snow anomaly over Tibet plays a role in weakening the western Pacific subtropical high in the simulated summer, whereas in reality the intensity of the high was stronger than normal in 2003.
Lead enrichment in Neotethyan volcanic rocks from Iran: The implications of a descending slab

Basic-intermediate volcanic rocks from the Karaj-Danesfahan area in the Neotethyan magmatic belt of Iran show typical island arc geochemical signatures. The rocks demonstrate calcalkaline affinity with low abundances of “high field strength elements” (HFSE) such as Nb, Ta, Hf and Ti, and highly distinctive spiked trace element patterns at “large ion lithophile elements” (LILE) such as Ba, K, and Sr. Comparing the geochemical characteristics of two sets of the volcanic rocks sampled from two parts of the study area 100 km apart, however, indicate subtle but significant geochemical differences which bear important petrogenetic implications. One set of the volcanic rocks is abnormally enriched in Pb and shows consistently higher abundances of HFSE, particularly Ti, than the other set. These two series are called HTL series (after high titanium and lead) and LTL series (after low titanium and lead), respectively. HTL series volcanic rocks are further from the subduction axis, so they should have had a deeper descending slab contributing to their mantle wedge magmatism. To be able to release Pb-enriched fluids, the subducting slab should not have undergone earlier dehydration. It is because Pb is highly incompatible. It appears that in the early stage, subduction proceeded at a higher rate (cold slab), so slab-dehydration occurred at greater depths triggering HTL series magmatism. Subsequently the subduction rate decreased which in turn raised isotherms and promoted partial melting at shallower depths leading to LTL series magmatism.
Middle Holocene Evolution of the Central Texas Coast

Abstract Recent work along the central Texas coast has suggested that middle Holocene sea level was slightly higher (+ 2 m) than present. This paper discusses some newly-recognized and/or reinterpreted mainland erosion surfaces and beach ridge plains of Holocene age that may represent the geomorphic manifestation of this highstand. Extensive erosion surfaces occur along bay margins, truncate weathered Pleistocene Ingleside sand at elevations of +2 m or more, and are overlain by swash zone and/or other bay margin deposits. Holocene beach ridge plains occur farther seaward from these erosion surfaces, and are underlain by more than 4 m of unweathered, massive to stratified sand. Holocene beach ridge plains are similar in scale to the modern barriers, since they attain elevations of +2.5 m, extend for tens of km along the mainland shore between Matagorda, San Antonio, Copano, and Corpus Christi Bays, and can be 1-3 km in width. Erosion surfaces are interpreted to represent wave ravinement along the shoreline of maximum transgression, whereas beach ridge plains are interpreted to represent progradation after maximum highstand, during sea-level fall to present elevations or lower.
On the triggering of Benguela Niños: Remote equatorial versus local influences

The relative importance of remote and local influences in the development of Benguela Niños is examined using observations and a coupled general circulation model capable of simulating interannual variability in the tropical Atlantic. While previous studies have emphasized the role of equatorially excited Kelvin waves, the present study finds that meridional wind anomalies along the southwest African coast contribute substantially. Both observations and model output indicate that sea‐surface temperatures along the southwest African coast respond rapidly to changes in meridional wind stress. These wind anomalies form part of a basin‐scale weakening of the subtropical anticyclone that extends to the equator. As the weakening begins three months before the peak of the event it might have some predictive potential. Results also indicate that the close correlation between Benguela and Atlantic Niños in observations might result from the large spatially coherent wind stress anomalies associated with the weakened anticyclone.
Duration of the Trans-Amazonian Cycle and Its Correlation within South America Based on U-Pb SHRIMP Geochronology of the La Plata Craton, Uruguay

The La Plata craton of Uruguay consists mostly of Paleoproterozoic terranes that are ideal for the investigation of the Trans-Amazonian Cycle evolution because, unlike the terranes of southeastern Brazil, they are unaffected by the Brasiliano collisional orogenies (640-590 Ma). The U-Pb isotopic dating of zircons from four Uruguayan rocks by the Sensitive High-mass Resolution Ion Micro Probe (SHRIMP II) shows an evolution from 2224 to 2056 Ma. We also extend the discussion of the cycle to the entire South American continent to provide a broad overview of the processes and belts involved. The Trans-Amazonian Cycle of South America consists of four main orogenies, of which three are present in the Uruguayan Piedra Alta (Isla Mala, Paso Severino, and Soca units) and Nico Pérez (Rivera and Valentines samples) terranes. All four Trans-Amazonian Cycle orogenies described in the classical Trans-Amazon orogen of the type-area (São Luís cratonic fragment, Gurupi belt) and in the Amazon craton are present in the La Plata craton. In Uruguay the second (2180-2120 Ma) and the third (2080-2050 Ma) Trans-Amazonian Cycle orogenies are well developed, whereas the oldest orogeny (2260-2200 Ma) is identified by only one inherited zircon (2224 Ma, Valentines granulite) and the fourth orogeny (2020-2010 Ma) has to be detected, but it is present in neighboring southern Brazil (Itapema, Camboriú, and Santa Maria-Chico units). The Rivera meta-trondhjemite was formed at 2140 ± 6 Ma, an epoch of granitoid-greenstone formation along all the Trans-Amazonian Cycle belts of South America, and by the Paso Severino felsic volcanics, formed at 2146 ± 7 Ma. The Rivera trondhjemite was metamorphosed at 2077 ± 6 Ma, a period characterized by intrusion of post-tectonic potassic granitoids and regional high-grade metamorphism. The metamorphism of the Valentines granulite is slightly younger (2058 ± 3 Ma) and this rock contains zircon with several inherited ages, such as 2224, 2163 (second orogeny), 2535, and 2619 Ma. The Soca charnockite is the youngest known Trans-Amazonian Cycle rock in Uruguay (2056 ± 6 Ma) and represents a continent-wide period of emplacement of post-tectonic, evolved granites and charnockites, such as the Calçoene charnockite (2059 Ma) of Amapá, Brazil. The data presented improve our understanding of tectonic processes active in South America during the Rhyacian Trans-Amazonian Cycle. However, the evolution of large segments of Paleoproterozoic crust and the Trans-Amazonian Cycle subdivision remain uncertain in many regions where U-Pb data are scarce or not available. The dating and characterization of these terrains require further investigation.
Sources and sinks of carbon from land‐use change in China

Changes in land use contribute to the current terrestrial carbon sink in most regions of the northern midlatitudes but are poorly documented for China, the world's third largest country. We attempted to reconstruct the last 300 years of land‐use change in China, emphasizing changes in the area of forests. Changes in the area of croplands were inadequate for reconstruction of forest loss because the long‐term loss of forest area was more than twice the current area of croplands. We used historical information to reconstruct changes in forest area over time and the ecological literature to estimate the carbon stocks of the major natural ecosystems (vegetation and soil). We used a bookkeeping model to calculate the flux of carbon to or from living vegetation, dead vegetation, soils, and wood products under different types of land use. According to the data and assumptions, 180 (range: 80–200) × 106 ha of forest were lost, and 17–33 PgC were released to the atmosphere between 1700 and 2000. About 25% of the loss was from soils. The accelerated clearing and logging of forests in northeastern and southwestern China led to emissions of carbon that reached peaks of 0.2–0.5 PgC yr−1 from the late 1950s through the 1970s. Lower rates of deforestation since then, as well as expanding areas of tree plantations, reversed the net flux of carbon from a source to a sink during the 1990s.
Improvisation and Performance in Software Development Teams: The Role of Geographic Dispersion

Software development teams are increasingly faced with unanticipated obstacles to effectiveness that require extemporaneous actions. Team improvisation has been identified as an important team situated response to emergent challenges to team effectiveness. However, the efficacy of team improvisation is not well understood in the context of software development teams—which perform complex, knowledge intensive tasks. We examine the efficacy of team improvisation in enhancing team effectiveness and identify team geographic dispersion as an important boundary condition. We test our hypotheses using data from 299 team leaders and members belonging to 71 teams. We find that team improvisation positively affects team performance, and that the degree of team geographic dispersion moderates the relationship between improvisation and team effectiveness. Theoretical and practical implications are offered.
A simple parameterisation for retrieving soil moisture from passive microwave data

Abstract. MICRO-SWEAT, a physically based soil water and energy balance model coupled with a microwave emission model, was used to investigate the relationship between near surface soil moisture (θ 0-5 ) and L -band microwave brightness temperature ( T B ) under a wide range of conditions. The effects of soil texture, look angle and vegetation on this relationship were parameterised and combined into a simple summary model relating θ 0-5 to T B . This model retains much of the physical basis of MICRO-SWEAT but can be used in more data limiting circumstances. It was tested using a variety of truck-based L -band data sets collected between 1980 and 1982. This paper emphasises the need to have an accurate estimate of the vegetation optical depth (a parameter that describes the degree of influence of the vegetation on the microwave emission from the soil surface) in order to retrieve correctly the soil water content. Keywords: passive microwave, soil moisture, remote sensing, vegetation, retrieval algorithm
Revisiting "the South" and "Dixie": Delineating Vernacular Regions using GIS

John Shelton Reed's maps of the South and Dixie in 1970s and 1980s indicated the shrinking boundaries of these two vernacular regions. This study revisits the South and Dixie. Using electronic telephone directories, this study collected all business names with "Southern" and "Dixie" in all the cities in the US. A univariate local indicator of spatial association (LISA) analysis was used to identify the clusters of high and low values of normalized values of the terms. These analyses helped identify the current core regions of Dixie land and the South. The results indicate that "the South" and "Dixie" boundary erosion is noticeable. The study identified a previously unnoticed island of "Dixie" in Utah. Southern and Dixie identities are stronger in non-metropolitan counties compared to metropolitan and micropolitan counties. Southern and Dixie identities are eroding gradually: while the erosion of southern identity is very slow, the erosion of Dixie identity seems to be faster. Overall, it may be more appropriate to refer "Dixieland" as "Dixie islands" today, but the South is still the South.
Investigation and application of the dressing action on surfaces of constant mean curvature

We investigate the dressing action on surfaces of constant mean curvature (CMC surfaces) in Euclidean space. In particluar, we show that for CMC surfaces with umbilics the isotropy group under dressing is always trivial. This result is applied to the investigation of CMC surfaces whose metric is invariant under a group of automorphisms of the parameter domain.
Diagenetic Carbonate in Miocene Sandstone Reservoir, San Joaquin Basin, California

Stevens arkosic sandstones, deposited about 7 Ma in a deep marine environment, form the North Coles Levee reservoir. Dolomite and calcite cements occur as zones averaging 1 ft thick and having less than 300 ft of lateral continuity. Based on ^dgr18O measurements and estimated pore fluids between 0 and 2.8, the dolomite formed at 30°-40°C, an early calcite cement formed at 50°-60°C, and a late pore-filling and plagioclase-replacing calcite formed at 70°-80°C. Corresponding to these temperature estimates, dolomite formed in the zone of methanogenesis (^dgr13C = 4 to 8) and calcites in the zone of decarboxylation (^dgr13C = -3 to -12). Dolomite has between 4 and 12 mole % Fe, and calcites contain up to 8 mole % o Fe + Mg + Mn with a characteristic (Fe + Mn)/Mg ratio of about 3:1. The latest calcite is the most Ca rich, due in part to Ca sourced from plagioclase dissolution. Calcite cements in nonmarine sections have markedly high Mn contents (to 5 mole %) compared with the marine section at North Coles Levee. The volume of cement systematically decreases from about 40-20% over the cementation temperature interval, suggesting progressive compaction of the sandstones. Present-day mean porosity of the reservoir (15%) appears to be largely a result of mechanical compaction. A very late dolomite cement with high Fe content (13 mole %) and light carbon (^dgr13C = -14) is found in the cleavage flakes of crushed biotite. The dolomite is calculated to have formed from a fluid with a ^dgr18O of 0.9 at present reservoir temperatures of 105°C, suggesting precipitation in the past 20 years during release of the gas cap and injection of isotopically light water. Calcite also forms thick scales in production tubing primarily as a result of pressure drops from 4,900 to 400 psi in the tubing string. The calcites have high Mg contents (7 mole %) due to the composition of the injection water. Calculated distribution coefficients for Fe and Mn are similar to published values, but Mg is two times higher than published values at 90°C. Similar results are obtained for late calcite cements. A time-temperature plot for North Coles Levee constrains the timing of dolomite cementation between 5 and 6 Ma and the calcite cementation between 4 and 2.5 Ma. Plagioclase dissolution and hydrocarbon emplacement occurred within the past few million years, suggesting that the presence of the hydrocarbons and associated byproducts of kerogen maturation enhance porosity. Despite the narrow window for diagenesis, minimum fluid fluxes of only 0.02 cm3/yr per 100 cm3 rock are required to account for the volume of dissolved plagioclase.
Slovak

Slovak (sometimes also called Slovakian) is an Indo-European language belonging to the West-Slavic branch, and is most closely related to Czech. Slovak is spoken as a native language by 4.6 million speakers in Slovakia (that is by roughly 85% of the population), and by over two million Slovaks living abroad, most of them in the USA, the Czech Republic, Hungary, Canada and Great Britain (Office for Slovaks Living Abroad 2009).
How Essential is Hydrologic Model Calibration to Seasonal Streamflow Forecasting

Abstract Hydrologic model calibration is usually a central element of streamflow forecasting based on the ensemble streamflow prediction (ESP) method. Evaluation measures of forecast errors such as root-mean-square error (RMSE) are heavily influenced by bias, which in turn is readily reduced by calibration. On the other hand, bias can also be reduced by postprocessing (e.g., “training” bias correction schemes based on retrospective simulation error statistics). This observation invites the question: How much is forecast error reduced by calibration, beyond what can be accomplished by postprocessing to remove bias? The authors address this question through retrospective evaluation of forecast errors at eight streamflow forecast locations distributed across the western United States. Forecast periods of length ranging from 1 to 6 months are investigated, for forecasts initiated from 1 December to 1 June, which span the period when most runoff occurs from snowmelt-dominated western U.S. rivers. ESP forecast .
Relationship of ENSO to snowfall and related cyclone activity in the contiguous United States

The relationship of the El Nino-Southern Oscillation to the contiguous U.S. snowfall was investigated using data from 3841 cooperative observer stations for the period 1951–1997. Snowfall for seven strong El Nino and five strong La Nina events was compared with snowfall occurring during the other 34 winters. The average snowfall for the seven El Nino winters exhibits a coherent large-scale pattern with below-average snowfall across approximately the northern half of the United States and above-average snowfall over the southwestern United States. Application of the t-test indicates that these snowfall anomalies are significantly different (at the 10% level) from the base period snowfall in parts of the mid-Mississippi River basin, the northern Ohio River basin, the western Great Lakes, and the northwestern United States. During strong La Nina winters, above-normal snowfall occurs in the northwest United States and northern Great Lakes. Although these anomalies do not pass tests of statistical significance (at the 10% level), the difference between La Nina and El Nino years is quite notable in the northwest United States. The results suggest that useful long-range outlooks of snowfall anomalies are possible for certain areas of the contiguous United States during strong El Nino events. An analysis of the frequency of strong cyclones (central pressure <992 hPa) shows that the El Nino winters were characterized by above-normal frequency in the extreme southern United States and below-normal frequency along the U.S.-Canadian border, with the pattern approximately reversed in the La Nina winters.