Miracle-dz/UniFAR-FTUs huggingface dataset:
Holocene vegetation and volcanic activity, Auckland Isthmus, New Zealand

A 12 000 to 4000 yr BP pollen and tephra-bearing profile from Auckland, New Zealand, provides insights into the vegetation history and evidence for early Holocene volcanic activity in this area centred on the Mount Wellington basaltic volcano. Possibly 500 yr separated initial scoriaceous ash deposition (ca. 9500 yr ago) and subsequent major lava flows (ca. 9000 yr ago) from Mount Wellington. The local vegelation, topography, and drainage patterns were substantially modified during this time, and damming by the lava flows resulted in the formation of Lake Waiatarua in a shallow valley head ca. 9000 yr ago. Diatom evidence indicates that this lake was initially deep (> 5 m) but was shallowing around 4000 yr ago. In contrast to the Mount Wellington eruptions, tephra deposition resulting from distant rhyolitic volcanic activity of the central North Island and Mayor Island has had little effect on the Auckland vegetation during this time interval (12 000–4000 yr ago). Between ca. 12 000 and 10 000 yr ago, conifer-angiosperm forest was the predominant vegetation cover on Auckland Isthmus, but during the early Holocene, forest dominated by Metrosideros expanded, probably on to fresh volcanic surfaces resulting from the Mount Wellington eruptions. At this time, swamp forest communities developed in Waiatarua valley basin, and included species indicative of moist, mild, relatively frost-free climates. Some taxa show histories consistent with other records from the northern New Zealand region, including the rise of Ascarina lucida ca. 11 000 to 9000 yr ago, and its subsequent decline, and the expansion of Agathis australis (kauri) forest communities from ca. 6000 yr ago. Taken together the history of local and regional vegetation points to a mild, moist and weakly seasonal early Holocene climate, which subsequently became drier with greater seasonal temperature extremes.
Temporal and spatial evolution of deepwater fold thrust belts: Implications for quantifying strain imbalance

Deepwater fold and thrust belts (DWFTBs) occur in a large number of active and passive continental margins, and their occurrence play an important role in controlling the structural configuration and stratigraphic evolution of margins. Although DWFTBs that are located on passive margins are a coupled system, in which updip extension is linked to downdip contraction, many studies have established a significant imbalance between these two domains in favor of net extensional strain. We have sequentially restored a series of parallel sections from the Orange Basin, South Africa, to quantify the amount of extension and contraction along a single collapse system. We found there to be a constant shortfall in the amount of contraction relative to extension in these features, which allowed us to quantify the lateral compaction of the margin as 5%. We also established a temporal model for the development and growth of thin shale detachment gravity collapse structures on passive margins. This model had implications not only for the kinematic and geometric evolution of these systems but also on the geomechanical process involved, in particular the accommodation of strain through compactional processes rather than discrete faulting.
An NMR Study of Shale Wettability and Effective Surface Relaxivity

Traditional methods of determining wettability such as the Amott and the U.S. Bureau of Mines (USBM) test for an oil/brine/rock system are difficult to apply to shales due to their extremely low permeability, usually in the nanodarcy range. Earlier Nuclear Magnetic Resonance (NMR) studies on Berea sandstone showed consistency with standard wettablity measurements and served as a calibration standard. A total of 10 core plugs from an Ordovician organic rich shale were analyzed. The T2 NMR signature of the imbibed dodecane and brine occurred mostly at relaxation times faster than their measured bulk relaxation of 1 and 3 second, respectively, indicating that surface relaxation is dominant. The Ordovician organic rich shale display mixed wettability. Three of the samples had a high affinity for dodecane, as a result of the organic pores present in the samples. This result was consistent with the NMR spectra in both sequences as well as the gravimetric analysis. The main advantage NMR has over the traditional methods is that we are able to see where the fluids are being imbibed. Mercury injection capillary pressure (MICP) characterizes the distribution of pore throats while NMR responds to the pore bodies. Assuming the throats and bodeies are equivalent, a scaling factor was used to match the NMR spectra and the MICP curves to estimate the effective surface relaxivity for the shale samples. The range of the effective surface relaxivities ranged between 0. 5μm/sec to 3. 1μm/sec with an average of 1.7 ± 1.0 μm/sec. Mineralogy variations were observed across the 10 shale samples but showed a correlation which suggests that the effective surface relaxivity is dependent on mineralogy.
Search for lower mantle high-velocity zones beneath the deepest Kuril and Mariana earthquakes

We perform travel time analyses for the Kuril and the Mariana subduction zones to investigate whether a lower mantle high-velocity zone exists immediately beneath the deepest earthquakes in these regions. We use P and PKIKP wave arrival time data read directly and accurately from WWSSN short-period vertical component records and corrected for the effect of lateral heterogeneity far from the source regions using a differential residual sphere technique. The corrected residuals for the deep Kuril events show that a high velocity zone extends in the down-dip direction of the Kuril slab in the lower mantle. On the other hand, the residuals for the deep Mariana events show no evidence for a high-velocity zone in the down-dip direction beneath the deepest earthquakes. A reasonable interpretation of these results is that the Kuril slab penetrates into the lower mantle (h≥670 km) but that the Mariana slab does not extend vertically into the lower mantle.
Observations of energetic neutral oxygen by IMAGE/HENA and Geotail/EPIC

Energetic neutral oxygen emissions from two satellites, IMAGE and Geotail, are examined during a magnetic storm interval on 2001 November 24–25. These two satellite observations provide different viewing perspectives of the energetic neutral emissions from the Earth's magnetosphere. IMAGE has a high inclination orbit while Geotail has a low one. Overlapping energy range of energetic neutral oxygen occurs for HENA on IMAGE and EPIC on Geotail. Quantitative comparison of oxygen energy spectra during this storm period indicates that viewing perspective plays an important role in the total intensity measured. This study constitutes the first quantitative inter‐spacecraft comparison of energetic neutral oxygen intensity.
Differences in El Nino Response over the Southern Hemisphere

Southern Hemisphere (SH) circulation conditions during austral springs of ENSO events are examined. Based on previous knowledge that SST variations over the subtropical south-central Pacific (SSCP) region are linked to differences among El Nino (EN) events, a stratification of the springs associated with EN events was performed according to SST conditions over the El Nino-3.4 sector and over the SSCP region. The EN events associated with cold conditions in the SSCP (WC) exhibit enhanced convection not only in the intertropical convergence zone over the central equatorial Pacific but also in the South Pacific convergence zone (SPCZ) extended south- eastward into the subtropical regions. The resulting heating forcing intensifies a localized overturning cell, which is associated with an anomalous Rossby wave source in the central South Pacific extratropical region. Neither the Rossby wave source nor the associated wave pattern is evident during EN events associated with warm conditions in the SSCP and inactive SPCZ (WW). The basic features that characterize the differences in the EN response over the South Pacific can also be identified through the analysis of the SPCZ activity over the central South Pacific. The fact that variations in SPCZ activity lead SST anomaly changes in the SSCP would indicate that the differences in the EN response over the SH might be mainly driven by atmospheric changes, which induces extratropical SST anomalies. The differences in the circulation anomalies that characterize both types of EN response over the SH were further explored through the analysis of the activity of the three leading modes of circulation variability. The combined effect of the three leading patterns describes in some extent the intensification (weakening) of the cyclonic circulation anomaly observed over the southeastern Pacific in WC (WW), associated with an active (inactive) SPCZ. In particular, the interdecadal variability observed in the Pacific by many previous studies influences the circulation response to ENSO over the SH, mainly through changes in the activity of the SH annular mode.
Estimate of top-of-atmosphere albedo for a molecular atmosphere over ocean using Clouds and the Earth's Radiant Energy System measurements

[1] The shortwave broadband albedo at the top of a molecular atmosphere over ocean between 40°N and 40°S is estimated using radiance measurements from the Clouds and the Earth's Radiant Energy System (CERES) instrument and the Visible Infrared Scanner (VIRS) aboard the Tropical Rainfall Measuring Mission satellite. The albedo monotonically increases from 0.059 at a solar zenith angle of 10° to 0.107 at a solar zenith angle of 60°. The estimated uncertainty in the albedo is 3.5 × 10−3 caused by the uncertainty in CERES-derived irradiances, uncertainty in VIRS-derived aerosol optical thicknesses, variations in surface wind speed and variations in ozone and water vapor. The estimated uncertainty is similar in magnitude to the standard deviation of 0.003 that is derived from 72 areas which are divided by 20° latitude by 20° longitude grid boxes. The empirically estimated albedo is compared with the modeled albedo using a radiative transfer model combined with an ocean surface bidirectional reflectivity model. The modeled albedo with standard tropical atmosphere is 0.061 and 0.111 at the solar zenith angles of 10° and 60°, respectively. The empirically estimated albedo can be used to estimate the direct radiative effect of aerosols at the top of the atmosphere over oceans.
Spectroscopic measurement of bromine oxide and ozone in the high Arctic during Polar Sunrise Experiment 1992

Bromine oxide (BrO) is proposed to be an important agent for tropospheric ozone depletion, as observed in the high Arctic during springtime. In this paper we report measurements of bromine oxide and ozone by Long Path Differential Optical Absorption Spectroscopy (LPDOAS), 8.6-km light path), performed in April 1992 in Alert (82.3°N, 62.2°W). BrO mixing ratios were found between the detection limit of about 4 ppt to 17 ppt. Because of the frequently poor visibility conditions, especially during ozone depletion events, long-signal integration times (sometimes more than 24 hours) were needed, and short-time BrO-peaks might have escaped detection. A pure in situ chemical mechanism based on BrO-catalyzed ozone destruction cannot account for the observed complete depletion of ozone at the observed BrO mixing ratios. On the other hand, it can be argued that the maximum time for chemical ozone depletion (by any mechanism) may not be much longer than 1 day. A simple scenario involving a combination of advection, atmospheric dispersion, and BrO-catalyzed chemical ozone destruction is described, which could explain the observed ozone loss.
Earthquake swarm in Steigen, northern Norway: an unusual example of intraplate seismicity

On the first of January 1992, unusual earthquake activity started in Steigen, northern Norway. By 31 December, 1992, a total of 207 events had been recorded in several pulses. Among these, several events with magnitudes larger than 3.0 (Mc) were also felt by the people. The epicentral distribution of these events seems to suggest that they all are concentrated in a small region (approximately 10 km in diameter) in the Brennvika Bay (67.8°N, 14.9°E), between Leinesfjorden in the north and Nordfolda in the south. The distribution of events in time is characteristic of a swarm in which no dear evidence of a mainshock–aftershock sequence was observed. Macroseismic intensity surveys as well as synthetic modelling indicate shallow focal depths in the range 5–8 km. Based on a composite focal mechanism, indicating an oblique-slip fault striking NE with a normal component dipping NW, combined with an observed NE trend in the epicentres and the focal depths, these events correlate with a previously proposed fault zone along Nordfolda. The NE trend has been dominant in the area throughout geological time, starting from the Caledonian Orogeny to the post-Caledonian basin developments, as well as the post-glacial and neotectonic structural features. At present, the deep-seated structural anomaly underneath the Lofoten Ridge seems to be the major factor controlling the structural trends in the area. The activity along the Nordfolda fault zone could be related to this large-scale structure, although the causes of the stresses that would create the seismic activity are not very clear, as there are several possible stress-generating mechanisms involved, such as post-glacial uplift of the land masses, the ‘ridge-push’ effect from Mohn's Ridge, and vertical stresses generated by the sediment loading in the adjacent basins.
Long‐wave radiation and heat flux estimates within a small tributary in Catamaran Brook (New Brunswick, Canada)

River water temperature is an important water quality parameter that also influences most aquatic life. Physical processes influencing water temperature in rivers are highly complex. This is especially true for the estimation of river heat exchange processes that are highly dependent on good estimates of radiation fluxes. Furthermore, very few studies were found within the stream temperature dynamic literature where the different radiation components have been measured and compared at the stream level (at microclimate conditions). Therefore, this study presents results on hydrometeorological conditions for a small tributary within Catamaran Brook (part of the Miramichi River system, New Brunswick, Canada) with the following specific objectives: (1) to compare between stream microclimate and remote meteorological conditions, (2) to compare measured long‐wave radiation data with those calculated from an analytical model, and (3), to calculate the corresponding river heat fluxes. The most salient findings of this study are (1) solar radiation and wind speed are parameters that are highly site specific within the river environment and play an important role in the estimation of river heat fluxes; (2) the incoming, outgoing, and net long‐wave radiation within the stream environment (under the forest canopy) can be effectively calculated using empirical formula; (3) at the study site more than 80% of the incoming long‐wave radiation was coming from the forest; (4) total energy gains were dominated by solar radiation flux (for all the study periods) followed by the net long‐wave radiation (during some periods) whereas energy losses were coming from both the net long‐wave radiation and evaporation. Conductive heat fluxes have a minor contribution from the overall heat budget (<3·5%); (5) the reflected short‐wave radiation at the water surface was calculated on average as 3·2%, which is consistent with literature values. Results of this study contribute towards a better understanding of river heat fluxes and water temperature models as well as for more effective aquatic resources and fisheries management. Copyright © 2011 John Wiley & Sons, Ltd.
The Impact of Anthropogenic Climate Change on North Atlantic Tropical Cyclone Tracks

AbstractThe authors examine the change in tropical cyclone (TC) tracks that results from projected changes in the large-scale steering flow and genesis location from increasing greenhouse gases. Tracks are first simulated using a Beta and Advection Model (BAM) and NCEP–NCAR reanalysis winds for all TCs that formed in the North Atlantic Ocean’s Main Development Region (MDR) for the period 1950–2010. Changes in genesis location and large-scale steering flow are then estimated from an ensemble mean of 17 models from phase 3 of the Coupled Model Intercomparison Project (CMIP3) for the A1b emissions scenario. The BAM simulations are then repeated with these changes to estimate how the TC tracks would respond to increased greenhouse gases. As the climate warms, the models project a weakening of the subtropical easterlies as well as an eastward shift in genesis location. This results in a statistically significant decrease in straight-moving (westward) storm tracks of ~5.5% and an increase in recurving (open oce.
Absolute absorption coefficients of ClONO2 infrared bands at stratospheric temperatures

Fourier-transform absorption spectroscopy has been used in the laboratory to obtain absolute absorption coefficients σ(ν) in infrared bands of ClONO2 in the 700–1800 cm−1 spectral region. These data have been obtained over a temperature range (213–296 K) corresponding to stratospheric temperatures. The results are therefore applicable to retrievals of stratospheric ClONO2 from remote-sensing observations. Room temperature absorption coefficients are some 25% larger than previously reported values, and large temperature dependences in the absorption coefficients have been observed. The ν1 and ν2 bands behave as simple fundamentals of a system which has low-energy vibrational or torsional modes, with little contribution from hot bands over the temperature range used. The intensity in the ν2 Q branch increased by 53% over the temperature range 296–213 K. A similar increase was observed for the ν4 Q branch, and significant hot-band features were seen in the ν3, ν4 spectral region. The ν4 Q branch and the ν2 Q branch were observed to obey the Beer-Lambert law over the range of pressure, temperature, absorber amount, and resolution employed. The absorption coefficients in the ν4 Q branch and in the ν2 band were modeled by equispaced absorption lines, each characterized by a central frequency, strength, lower-state energy, and pressure-broadened width.
Investigation of the Interannual Variability of the Tropical Atlantic Ocean from Satellite Data

The interannual variability of the tropical Atlantic Ocean is analyzed from 1992 to 2011 using statistical decompositions of different satellite data such as altimetric series. Three regions of maximum variability are highlighted: a northern one, between 10 and 20°N; a southern region, along 20°S; and an equatorial region. This variability is due to both local and remote wind activity. The teleconnections with the tropical Pacific El Niňo–Southern Oscillation indicate a possible connection of the tropical Atlantic between 10 and 20°N with a 4-month delay, and in the Gulf of Guinea with a 16-month delay.
Alternative to Agricultural Drains in California's San Joaquin Valley: Results of a Regional-Scale Hydrogeologic Approach

The occurrence of selenium in agricultural drainage water derived from the central part of the western San Joaquin Valley has focused concern on alternatives to agricultural drains for managing shallow, poor-quality groundwater. A transient, three-dimensional simulation model was developed to evaluate the response of the water table to alternatives that affect recharge to or discharge from the groundwater flow system. The modeled area is 551 mi2 (1 mi2 = 2.59 km2) and includes both the semiconfined and confined zones above and below the Corcoran Clay Member of the Tulare Formation of Pleistocene age. The simulation model was calibrated using hydrologic data from 1972 to 1988, and was extended to the year 2040 to forecast for various management alternatives, including maintenance of present practices, land retirement, reduced recharge, increased groundwater pumping, and combinations of these alternatives. Maintenance of present practices results in a worsening of the situation: the total area subject to bare-soil evaporation increases from 224 mi2 in 1990 to 344 mi2 in 2040, and drain flow increases from 25,000 ac ft/yr (1 ac ft = 1234 m3) to 28,000 ac ft/yr. Although land retirement results in elimination of bare-soil evaporation and drain flow in the areas retired, it has little to no effect in adjacent areas. In contrast, regional-scale changes in recharge and pumping are effective for regional management. The area subject to bare-soil evaporation can be reduced to 78 mi2, and drain flow to 8000 ac ft/yr if (1) recharge is reduced by 15% (26,000 ac ft/yr) in areas that currently use surface and groundwater (362 mi2); (2) recharge is reduced by 40% (28,000 ac ft/yr) in areas that currently use only surface water (137 mi2); and (3) pumping rates are uniformly incremented by 0.5 ft/yr (160,000 ac ft/yr) in both areas. If these water budget changes were to be implemented in the study area, and in adjacent areas with similiar Hydrogeologic characteristics, then approximately 400,000 ac ft/yr of surface water would be made available. Thus a shift in the hydrologic budget in the central part of the western San Joaquin Valley improves the prospects for sustaining agriculture in the area, and could provide substantial water resources for other uses.
Seasonal development of spatial snow-depth variability across different scales in the Swiss Alps

Abstarct The depth of snow cover is temporally and spatially heterogeneous at different scales in Alpine regions. For snow hydrology/climatology the spatial variability of snow depths is a key parameter for capturing the total amount of snow in a given area. Here a scale analysis of the spatial variability of snow depths during the accumulation period is investigated. The development of the variability is characterized by a parameter, β, describing the relationship between the standard deviation and the mean of snow depths. The analysis includes two datasets: (1) 141 snow-depth point measurements representing flat-field observations, and (2) snow precipitation from the numerical weather prediction model COSMO-7. The results reveal that β is almost invariant at scales between 10 and 300 km. The COSMO-7 data exhibit the same scale invariance above 50 km, indicating that the spatial variability of snow depths is formed by the precipitation pattern at these scales. The scaling analysis of β allows determination of the absolute accuracy of estimating the total amount of snow in a given area and helps to validate different snow models or remote-sensing techniques by ground truth verification.
An empirical evolution law of fractal size frequency of fault population and its similarity law

Size (displacement) frequencies of 10 fault populations follow a power‐law associated with cut‐off in the range smaller than a characteristic size. They are depicted by five geometrical parameters of fault population; cut‐off size, sharpness of cut‐off, fault number density, fault displacement density and the power‐law exponent. The former three are rock properties related to dissipative energy density and constitute the similarity law of the size frequency. The fault displacement density is a measure of total input energy density. The power‐law exponent decreases as the − 1/4 power of total input energy density normalized by dissipative energy density.