Miracle-dz/UniFAR-FTUs huggingface dataset:
Error estimates of background atmospheric CO2 patterns from weekly flask samples

The precision and accuracy of trends and seasonal cycles of CO{sub 2}, as determined from grab samples, was investigated. First, the statistical aspects of infrequent (weekly) sampling were studied by simulating, via a partially random procedure, parallel time series of CO{sub 2} flask samples. These simulated flask series were compared to the continuous analyzer records from which they had been derived. The second approach to studying the uncertainties of flask records was to compare real flask results with simultaneous hourly mean concentrations of the in situ analyzers at the Geophysical Monitoring for climatic Change observatories at Point Barrow, Mauna Loa, Samoa, and the south pole. The latter comparisons emphasized experimental, rather than statistical, errors. The uncertainties and sampling biases depend on the site and on the period of averaging. For monthly means the uncertainty varies from 0.2 to 0.6 ppm (one standard deviation, parts per million by volume), being largest for Barrow. Sampling biases for monthly means at Barrow and Mauna Loa are significant, up to 0.5 ppm. Experimental errors are the dominant error source for annual averages, and spurious interannual variations can be up to 0.4 ppm.
Heat flow, heat generation, and crustal temperatures in the northern Canadian Cordillera: Thermal control of tectonics

[1] The heat flow in the northern Canadian Cordillera between 59 and 64 N is very high, 105 ± 22 mW/m2. The average upper crust heat generation is 4.6 ± 2.4 microW/m3, giving a reduced deep heat flow of 59 mW/m2, similar to the southern Canadian Cordillera, 49–53 N. Estimated Moho temperatures of 800–1000°C and lithosphere only 50–60 km thick are substantiated by slow upper mantle seismic velocities and by high elevations associated with crust only 32–35 km thick. The new data support the conclusion that all of the North and South America Cordilleras are hot. The Paleoproterozoic Wopmay orogen to the east has a remarkably high heat flow of 90 ± 15 mW/m2 for such an old and stable region. However, basement samples indicate high heat generation and estimated deep temperatures are intermediate between the Cordillera and the Slave Craton further to the east. Heat flow from the Yellowknife area of the Slave Craton, 53 mW/m2, implies low lithosphere temperatures in agreement with kimberlite xenolith P-T data. The high temperatures in the Cordillera result in a very thin and weak lithosphere and may allow a lower crust detachment. The north and central Cordillera have been inland of the coastal Queen Charlotte transform fault since subduction stopped in the Eocene. Thus some process has maintained high temperatures in the former back arc for more than 40 Ma.
Determination of Pressure Dependent Leakoff and Its Effect on Fracture Geometry

The effects of natural fissure opening, or pressure dependent leakoff, on the pressure behavior observed during fracturing are significant. Previous work has suggested that this behavior can be identified from pressure diagnostic plots during pumping, or from pressure falloff analysis. However, these techniques lead to ambiguous conclusions regarding the magnitude, and even existence, of pressure dependent leakoff. This paper presents a method of pressure falloff analysis which removes this ambiguity and allows an accurate determination of the magnitude of pressure dependent leakoff. The effects of fracture tip extension and recession, height recession, and transient flow in the fracture are also identified. The effect of pressure dependent fracture compliance, which has not been previously published, is also described.
Temporal and spatial soil moisture change pattern detection in an agricultural area using multi‐temporal Radarsat ScanSAR data

Monitoring the characteristics of spatially and temporally distributed soil moisture is important to the study of hydrology and climatology for understanding and calculating the surface water balance. The major difficulties in retrieving soil moisture with Synthetic Aperture Radar (SAR) measurements are due to the effects of surface roughness and vegetation cover. In this study we demonstrate a technique to estimate the relative soil moisture change by using multi‐temporal C band HH polarized Radarsat ScanSAR data. This technique includes two components. The first is to minimize the effects of surface roughness by using two microwave radar measurements with different incidence angles for estimation of the relative soil moisture change defined as the ratio between two soil volumetric moistures. This was done by the development of a semi‐empirical backscattering model using a database that simulated the Advanced Integral Equation Model for a wide range of soil moisture and surface roughness conditions to characterize the surface roughness effects at different incidence angles. The second is to reduce the effects of vegetation cover on radar measurements by using a semi‐empirical vegetation model and the measurements obtained from the optical sensors (Landsat TM and AVHRR). The vegetation correction was performed based on a first‐order semi‐empirical backscattering vegetation model with the vegetation water content information obtained from the optical sensors as the input. For the validation of this newly developed technique, we compared experimental data obtained from the Southern Great Plain Soil Moisture Experiment in 1997 (SGP97) with our estimations. Comparison with the ground soil moisture measurements showed a good agreement for predication of the relative soil moisture change, in terms of ratio, with a Root Mean Square Error (RMSE) of 1.14. The spatially distributed maps of the relative soil moisture change derived from Radarsat data were also compared with those derived from the airborne passive microwave radiometer ESTAR. The maps of the spatial characteristics of the relative soil moisture change showed comparable results.
Vegetation characteristics and the prediction of runoff: Analysis of an experiment in the New Forest, Hampshire

Vegetation characteristics have not been sufficiently utilized in catchment runoff models. An analysis of storm hydrograph data from nested subareas of the Highland Water catchment, New Forest, U.K., indicates that depth of runoff and peak discharge from areas under heathland cover is substantially greater than from areas under woodland cover at several spatial scales. The significance of heath vegetation composition in the identification of runoff contributing areas is illustrated by an analysis of vegetation composition, water table depth, baseflow discharge and storm runoff from areas predominantly covered by heathland. Methods are proposed to employ the hydrological characteristics of heathland to refine and develop the Flood Studies Approach to discharge estimation in ungauged heathland catchments. Such an approach is greatly facilitated by the use of remotely-sensed data.
INTERDISCIPLINARY GROUP EXPLORES SEAFLOOR ERUPTION WITH REMOTELY OPERATED VEHICLE

One of the most successful open-ocean, interdisciplinary expeditions using a remotely operated vehicle was conducted last year and is being looked on as a harbinger for future deep submergence expeditions. Unmanned systems have emerged in the past decade as an alternative to manned submersibles for deep-ocean studies. But until now they have not proven themselves to be equal to manned vehicles in conducting multiple sampling tasks in an interdisciplinary milieu. Last year's expedition involved extensive investigations and sampling using the Canadian Remotely Operated Vehicle for Ocean Sciences (ROPOS) [Shepherd and Juniper, 1997]. A team of 33 chemists, biologists, geologists, and engineers, including a number of principal investigators from the United States and Canada, sailed on the Ronald H. Browne National Oceanic and Atmospheric Administration (NOAA) ship, with ROPOS to investigate in detail the aftermath of a diking event in the Pacific Ocean and its effect on hydrothermal chemistry and on seafloor and subseafloor biological communities. The expedition was part of the New Millennium Observatory (NeMO) project and began in earnest the in situ portion of the project in August 1998.
Quantifying riverine surface currents from time sequences of thermal infrared imagery

River surface currents are quantified from thermal and visible band imagery using two methods. One method utilizes time stacks of pixel intensity to estimate the streamwise velocity at multiple locations. The other method uses particle image velocimetry to solve for optimal two‐dimensional pixel displacements between successive frames. Field validation was carried out on the Wolf River, a small coastal plain river near Landon, Mississippi, United States, on 26–27 May 2010 by collecting imagery in association with in situ velocities sampled using electromagnetic current meters deployed 0.1 m below the river surface. Comparisons are made between mean in situ velocities and image‐derived velocities from 23 thermal and 6 visible‐band image sequences (5 min length) during daylight and darkness conditions. The thermal signal was a small apparent temperature contrast induced by turbulent mixing of a thin layer of cooler water near the river surface with underlying warmer water. The visible‐band signal was foam on the water surface. For thermal imagery, streamwise velocities derived from the pixel time stack and particle image velocimetry technique were generally highly correlated to mean streamwise current meter velocities during darkness (r2 typically greater than 0.9) and early morning daylight (r2 typically greater than 0.83). Streamwise velocities from the pixel time stack technique had high correlation for visible‐band imagery during early morning daylight hours with respect to mean current meter velocities (r2 > 0.86). Streamwise velocities for the particle image velocimetry technique for visible‐band imagery had weaker correlations with only three out of six correlations performed having an r2 exceeding 0.6.
Tropical Atlantic Variability Modes (1979–2002). Part II: Time-Evolving Atmospheric Circulation Related to SST-Forced Tropical Convection

Abstract The ways in which deep convection over the tropical Atlantic affects the midlatitude climate variability through meridional circulation, planetary wave teleconnection, and wave–mean flow interaction is examined for the 1979–2002 period, by following the North Atlantic anomalous rainfall evolution from summer to late winter. In this way, the first two covariability modes between anomalous summer tropical Atlantic sea surface temperature (SST) and anomalous summer–late-winter precipitation over the North Atlantic basin are analyzed using the same methodology of extended maximum covariance analysis developed for Part I. This work updates the results given by other authors, whose studies are based on different datasets dating back to the 1950s. To this end, the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) dataset, which includes measures over the ocean, is used to give a complete picture of the interannual rainfall patterns for the last decades. The first mode, which accoun.
Changes in seismicity before and after the 2011 Tohoku earthquake around its southern limit revealed by dense ocean bottom seismic array data

The southern limit of the 2011 Tohoku earthquake is considered to be located around off Ibaraki. However, it is not well constrained how far south the large slip extended. To give better constraints, we investigated seismicity including small earthquakes before and after the Tohoku earthquake around off Ibaraki using dense ocean bottom seismic array data. We automatically identified epicenters by backprojecting semblance values resulting in a considerable increase in the number of detected events compared with those listed in the catalog based on onshore observation. The results revealed a couple of seismicity‐activated region. The largest aftershock also occurred ~30 min after the main shock. Our detailed results suggest that this highly activated seismicity was initiated by the largest aftershock instead of the main shock. It, then, suggests that the large coseismic slip zone of the Tohoku earthquake may not have extended off Ibaraki.
New Method for 3D and Asymmetrical Slope Stability Analysis

A new three-dimensional (3D) slope stability analysis method is developed based on two-directional moment equilibrium. This method calculates not only the safety factor but also the possible direction of sliding for semispherical and composite failure surfaces. As a result, the possible errors associated with assuming a plane of symmetry in 3D stability analyses are eliminated. Another advantage of the new method is to eliminate the tedious work on the coordinate transformation prior to the analysis. Two examples of symmetrical failure surfaces are used to verify the basic formulation in the present study. Three additional examples further demonstrate the applicability of the proposed method in analyzing 3D asymmetrical failure surfaces. An analysis on a slope, subject to asymmetrical excavation unloading and geological conditions, shows that using the method of one-directional moment equilibrium may give an overestimated safety factor of the slope.
Reliable Displacement Response Spectra at Long Periods in the Near Field of Large Earthquakes

Displacement response spectra defined up to long periods are needed for the design of large structures and to design structures according to displacement‐based methods. The spectra can theoretically be retrieved in the near field of large earthquakes from accelerations recorded by modern strong‐motion accelerometers. Difficulties exist due to instrumental limitations: long‐period noise that contaminates the acceleration time histories and record of the tilt simultaneously to the translational accelerations. Original in this work, the effect of the instrument’s permanent tilt is investigated, and the improvement of the spectra at long periods, when the residual tilt is removed from accelerations recorded by modern strong‐motion seismometers, is checked against 1 Hz Global Positioning System (GPS) measurements. Records of five strong‐motion accelerometers situated in the near field of the M w 6.8 Japanese 2007 Niigata‐ken Chuetsu‐Oki earthquake are analyzed in terms of Fourier content and displacement response spectra and are then compared to their closest 1 Hz GPS data. The results show that the uncorrected acceleration time histories, obtained by simply removing the preevent mean from the raw accelerations recorded by modern strong‐motion seismometers, provide reliable displacement response spectra at periods over 20 s. Corrected acceleration time histories, obtained by removing the permanent tilt from the uncorrected records using the Javelaud et al. (2011) method, may provide reliable response spectra at very long periods until they reach the theoretical peak ground displacement.
Competition Versus Optimal Control in Groundwater Pumping When Demand is Nonlinear

This article considers the issue of optimal control versus no control in groundwater pumping under the assumption of a nonlinear demand function for water use. We confirm for the case of the nonlinear demand function what had been demonstrated for the case of a linear demand function: namely, if water rights are properly defined and if the storage capacity of the aquifer is relatively large, the difference between a strategy of no control and a strategy of optimal control is small and thus can be ignored for practical policy considerations. Furthermore, we demonstrate that even if simulated optimal control yields slightly better results than no control, a strategy of no control is likely to yield better results than optimal control, unless we can be sure that the estimated demand for groundwater is very close to the true demand.
Mapping Clay Content across Boundaries at the Landscape Scale with Electromagnetic Induction

Detailed information on soil textural heterogeneity is essential for land management and conservation. It is well known that in individual fields, measurement of the soil's apparent electrical conductivity (EC a ) offers an opportunity to map the clay content of soils with free drainage under a humid climate. At the catchment scale, however, units of different land management and differing sampling dates add variation to EC a and constrain the mapping across field boundaries. We analyzed their influence and compared three approaches for applying electromagnetic induction (EM v ) to clay-content mapping at the landscape scale across the boundaries of individual fields and different sampling dates. In the study region, a separate calibration of the relation between clay and EC a for each field and sampling date (fieldwise calibration) yielded satisfactory clay-content predictions only if the costly precondition of sufficient calibration points for each field was fulfilled. We propose a method (nearest-neighbors EC a correction) for unifying EC a across boundaries based only on the EC a data themselves, and the assumption of continuity of textural properties at field boundaries, which was fulfilled in the landscape studied. Prediction is calibrated once for the entire landscape, which allows a reduced set of calibration points. The coefficient of determination for predicting clay content (here, including silt <4 μm) was improved from R 2 = 0.66 (no correction for land use and sampling date) to R 2 = 0.85 (n = 46). With the method developed, EC a offers a powerful and cheap method of clay-content mapping in agricultural landscapes.
Estimation of suspended solids using Indian Remote Sensing Satellite-IA data: a case study from Central India

Abstract The objective of this study was to use Indian Remote Sensing Satellite-IA (IRS-1A) Linear Imaging Self Scanning-I (LISS-I) digital data in combination with field measurement for the estimation of suspended solids concentration in an inland water body (reservoir). For this purpose, a small reservoir (Tawa), on the Tawa river of the Narmada basin in Central India, was studied. The Tawa reservoir water samples were collected on 28 September and 20 October 1988, concurrent with IRS-1A overpass. Reservoir water samples have been analysed to determine grain size analysis and mineralogy.
A Coupled Air-Sea Biennial Mechanism in the Tropical Indian and Pacific Regions: Role of the Ocean

Abstract Variations in the upper-ocean beat content are part of a mechanism to explain biennial signals in the tropical Indian and Pacific ocean regions. The mechanism involves modulations of the annual cycle of convection and processes of the dynamically coupled ocean and atmosphere system in the tropics. A critical element of that mechanism is persistent sea surface temperature anomalies on the time scale of one seasonal cycle. Analyses of composite vertical temperature profiles from hydrographic station data for various near-equatorial areas in the Indian and Pacific oceans show that variations in the ocean heat content depend on the depth of the thermocline in the warm-pool region (both eastern Indian and western Pacific) and temperatures in the upper-ocean mixed layer away from the warm pool (western Indian and eastern Pacific). The variations in thermocline depth in the Pacific are similar to those for El Nino-Southern Oscillation (ENSO) events and are present in the biennial mode as well. Apparentl.
The Steinmann Trinity revisited: mantle exhumation and magmatism along an ocean-continent transition: the Platta nappe, eastern Switzerland

Abstract The close association of serpentinites, basalts and radiolarites, later known as the Steinmann Trinity, was clearly described by Steinmann from the south Pennine Arosa zone and its southern prolongation, the Platta nappe of the eastern Swiss Alps. This classical ‘ophiolite’ is distinctly different from typical fast-spreading ridge associations and can be compared with the transitional crust occurring along non-volcanic passive continental margins in present-day oceans. It includes serpentinized peridotites that we interpret as subcontinental mantle rocks, which were exhumed along low-angle detachment faults and locally overlain by extensional allochthons of continental crust, minor gabbroic intrusions, tholeiitic pillow lavas and flows and a succession of oceanic sediments. The serpentinized peridotites record deformation at falling temperatures during extension leading to final exposure of the mantle rocks at the sea floor and their inclusion in tectono-sedimentary breccias (ophicalcites). Field relationships, and mineral-chemical and radiometric data show that the gabbros intruded already serpentinized mantle rocks at shallow depth 161 Ma ago. They are Mg gabbros, Fe gabbros and Fe-Ti gabbros, cut by dioritic pegmatoid veins and albitite dykes, which originated by differentiation from the same parental magma. All gabbros show the same metamorphic evolution, i.e. intrusion at relatively low pressure, oceanic hydration at elevated temperature and a subsequent static oceanic alteration. The pillow lavas stratigraphically overlie the exhumed mantle rocks and the tectono-sedimentary breccias related to the exhumation of both mantle rocks and gabbros. However, both gabbros and pillow basalts are characterized by εNd values typical for an asthenospheric mid-ocean ridge-type source of the melts. They may be the products of a steady process that combined extensional deformation with magma generation and emplacement. They appear to document the onset of sea-floor spreading across an exhumed subcontinental mantle during the earliest phases of a slow-spreading ridge.
Seismic hazard in western Canada from GPS strain rates versus earthquake catalog

[1] Probabilistic seismic hazard analyses (PSHA) are commonly based on frequency - magnitude statistics from 50–100 yearlong earthquake catalogs, assuming that these statistics are representative of the longer-term frequency of large earthquakes. We test an alternative PSHA approach in continental western Canada, including adjacent areas of northwestern U.S.A. , using regional strain rates derived from 179 Global Positioning System (GPS) horizontal velocities. GPS strain rates are converted to earthquake statistics, seismic moment rates, and ground shaking probabilities in seismic source zones using a logic-tree method for uncertainty propagation. Median GPS-based moment rates and shaking estimates agree well with those derived from earthquake catalogs in only two zones (Puget Sound and mid-Vancouver Island). In most other zones, median GPS-based moment rates are 6–150 times larger than those derived from earthquake catalogs (shaking estimates 2–5 times larger), although the GPS-based and catalog estimates commonly agree within their 67% uncertainties. This discrepancy may represent an under-sampling of long-term moment rates and shaking by earthquake catalogs in some zones; however a systematic under-sampling is unlikely over our entire study area. Although not demonstrated with a high confidence level, long-term regional aseismic deformation may account for a significant part of the GPS/catalog discrepancy and, in some areas, represent as much as 90% of the total deformation budget. In order to integrate GPS strain rates in PSHA models, seismic versus aseismic partitioning of long-term deformation needs to be quantified and understood in terms of the underlying mechanical processes.