Miracle-dz/UniFAR-FTUs huggingface dataset:
An analytical algorithm for the determination of vegetation Leaf Area Index from TRMM/TMI data

In this paper, an analytical algorithm for the determination of land surface vegetation Leaf Area Index (LAI) with the passive microwave remote sensing data is developed. With the developed algorithm and the Tropical Rainfall Measuring Mission/Microwave Imager (TRMM/TMI) remote sensing data collected during the Global Energy and Water Experiment (GEWEX) Asian Monsoon Experiment in Tibet (GAME/Tibet) Intensive Observation Period (IOP'98), the regional and temporal distributions of the land surface vegetation LAI have been evaluated. To validate the developed algorithm and the retrieval results, the maximum-composite Normalized Difference Vegetation Index (NDVI) data over the same study area and period are used in this study; the cloud contaminated NDVI values have been replaced by the cloud-free values reconstructed by the Harmonic ANnalysis of Time Series (HANTS) technique. The results show that the retrieved LAI is in good agreement with the cloud-free NDVI in regional and temporal distributions and in their statistical characteristics; the vegetation characteristics can be clearly assessed from the regional distribution of the retrieved LAI. As lower frequency microwave radiation can penetrate atmosphere and thin cloud layer, with the application of the passive microwave remote sensing data, the developed algorithm can be used to monitor the land surface vegetation condition more effectively.
Comparison of SAR-interferometric and surveyed velocities on a mountain glacier: Black Rapids Glacier, Alaska, U.S.A.

Abstract An interferogram reflecting the motion of Black Rapids Glacier, Alaska, U.S.A. , was obtained from two European Remote-sensing Satellite (ERS-1) syntheticaperture radar (SAR) images, acquired on 22 and 25 January 1992. We investigate whether the interferometric data are quantitatively consistent with terrestrial velocity measurements along three transverse profiles. These terrestrial data are from different years (1987, 1990, 1996) and cover different periods (6–28 April, 23 May–7 July and a whole year) than the SAR interferogram. Terrestrial ice velocity at the date of the SAR imagery is obtained via seasonal and annual corrections that are calculated from other terrestrial velocity measurements available at higher time resolution for selected sites on the glacier. Interferometric and terrestrial velocity are in excellent agreement if a (terrestrially measured) surface-normal velocity component (v ⊥) is properly accounted for. This suggests that both the interferometric velocities and the conversions of terrestrial data to the winter period are reliable. The terrestrial velocity measurements show that ice flow in the upper ablation area (14–16 km sites) changes from longitudinal compression in mid-winter (v ⊥ = + 0.82 cm d−1) to moderate longitudinal extension during summer (v ⊥ ≈ –0.25 cm d−1). In the lower ablation area, the seasonal variations of the longitudinal strain rate are much smaller: +1.0 and about +0.85 cm d−1 for the respective mid-winter and summer values of v ⊥ at the 20 km site.
Biogeography and evolution of hydrothermal-vent fauna in the eastern Pacific Ocean

The biogeography and evolutionary history of animals that live at hydrothermal vents are connected intimately to the spreading history of mid-ocean ridges. Extensive collections from two active ridge systems in the eastern Pacific Ocean provide an opportunity to examine the regional dispersion of vent-limited organisms. The degrees to which these habitat-limited species from disjunct areas are related gives preliminary information about exchange routes, dispersability, and rates of taxonomic change. Differences between vent faunae from the northern Juan de Fuca and southern East Pacific Rise systems indicate that geographical differentiation has occurred. Geophysical evidence shows that North America interposed as a barrier between the northeast and equatorial Pacific spreading ridges about 35 Ma BP. The vicariating vent fauna of the Juan de Fuca Ridge has since formed an endemic assemblage of generally lower diversity than that found at East Pacific Rise vents. Taxonomic comparisons suggest that rates of speciation have been low. Examination of spreading histories elsewhere should provide predictions of evolutionary patterns in the hydrothermal-vent faunae.
Efficient Dynamic Phasor Model of Distributed Photovoltaic Systems

The computational challenge in solving dynamic models of power distribution grids increases with the high penetration of distributed photovoltaic (PV) systems. The existing dynamic models of PV systems are overly detailed and computationally intractable for solving distribution grid dynamics with a large number of distributed PV systems. As IEEE-1547 requires smart PV inverters to support the grid voltage and frequency dynamically, this motivates to develop an accurate and computationally efficient dynamic model of distributed PVs. Therefore, in this work, a dynamic phasor model of smart PV inverters is developed and compared with an existing electromagnetic transient model (detailed model) in terms of accuracy and computational efficiency. The results show a remarkably fast solve time of the proposed dynamic phasor model compared to that of the detailed model (more than 30 times speed up), while sufficiently capturing necessary volt-var, volt-watt, and frequency-watt dynamics during the normal, and voltage ride-through and frequency ride-through events.
The Last Pterosaurs: First Record from the Uppermost Maastrichtian of the Tremp Syncline (Northern Spain)

Pterosaur bones are for the first time reported from the Tremp Syncline (Spain) and the southern Pyrenees. They come from the Torrebilles‐2 site (Isona, Lleida Province) in the upper Maastrichtian part of the Tremp Formation, which falls within the C29r magnetochron. Fragmentary long bones are referred to the Pterosauria based on their cortical thinness, micro‐architecture, and histological features. They belong to very large to possibly giant individuals. The most complete specimen is possibly a partial right femur. The review of the Maastrichtian pterosaur record shows that only a few specimens can be referred to the C29r (which contains the K/Pg boundary). The identification of fragmentary remains could improve our knowledge about the abundance and distribution of these flying sauropsids just before the end‐Cretaceous mass extinction.
Shrub Expansion in SW Greenland Under Modest Regional Warming: Disentangling Effects of Human Disturbance and Grazing

Abstract Shrub expansion has been observed widely in tundra areas across the Arctic. This phenomenon has been partially attributed to increasing temperatures over the past century. However, relationships among shrub expansion, grazing, and human disturbance have been studied little. SW Greenland is a subarctic to low-arctic region with a long and complex land-use history and only modest temperature increases over the past 50 years (0.2 °C decade-1), but changes in shrub cover have not previously been studied in this region. We compiled historical photographs of vegetation in SW Greenland (1898–1974) and repeated the photos in 2010 and 2011. Sixty-four photo pairs were cropped into 133 smaller units and classified by aspect, substrate stability, muskoxen grazing, and human disturbance. The photo material was evaluated by 22 experts with respect to changes in shrub cover, revealing a general increase across the whole data set, and in a subset including only undisturbed sites. Shrub cover increased most on E and SE slopes, in sites with stable substrate, and in areas characterized by human disturbance and without muskoxen grazing. The general shrub cover increase could be caused mainly by changed land-use intensity, but effects of the moderately increased temperatures cannot be ruled out.
Hydraulics of subglacial outburst floods: new insights from the Spring-Hutter formulation

Using a slightly modified form of the Spring-Hutter equations, glacial outburst floods are simulated from three classic sites, Hazard Lake, Yukon, Canada, Summit Lake, British Columbia, Canada, and Grimsvotn, Iceland, in order to calibrate the hydraulic roughness associated with subglacial conduits. Previous work has suggested that the Manning roughness of the conduits is remarkably high, but the new calibration yields substantially lower values that are representative of those for natural streams and rivers. The discrepancy can be traced to a poor assumption about the effectiveness of heat transfer at the conduit walls. The simulations reveal behaviour that cannot be interred from simplified theories: (1) During flood onset, water pressure over much of the conduit can exceed the confining pressure of surrounding ice. (2) Local values of fluid potential gradient can differ substantially from the value averaged over the length of the conduit, contradicting an assumption of simple theories. (3) As the flood progresses, the location of flow constrictions that effectively control the flood magnitude can jump rapidly over large distances. (4) Predicted water temperature at the conduit outlet exceeds that suggested by measurements of exit water temperature.
Radical chemistry at a forested continental site: Results from the PROPHET 1997 campaign

[1] Radical chemistry at a forested site in northern Michigan has been examined using measurements made by a radical amplifier system in the summer of 1997. The radicals show a diurnal variation with the maximum concentration being measured several hours after solar noon. Low but observable concentrations were present at night, but these levels are inconsistent with the previously postulated active nighttime chemistry driven by high concentrations of highly reactive hydrocarbons. A box model, constrained by measured concentrations of CO, O3, NO, NO2, isoprene, and peroxyacetylnitrate, was found to simulate both the maximum concentrations and their diurnal variation. Model sensitivity studies indicate that 54% of the radical production comes from sources other than ozone photolysis, and the presence of isoprene has an impact on the radical concentration through impacts on both radical production and loss.
Seasonal variation of N2O and CH4 fluxes in differently managed arable soils in southern Germany

Agricultural practices are assumed to contribute significantly to the increase in atmospheric nitrous oxide (N 2 O) concentrations observed in the last decades, and they might influence the consumption of atmospheric methane (CH 4 ) by soil. The aim of this study was to quantify the effects of management intensity, soil type, and frost periods on the emission of N 2 O and the consumption of CH 4 in rotations in southern Germany. Fluxes of N 2 O and CH 4 were monitored over 12 months, using a closed chamber technique. The extensively managed system was cropped to sunflower and fertilized with farmyard manure (12 t ha −1 ). The intensively managed field was planted with spring wheat and fertilized with a total of 190 kg N ha −1 given as calcium ammonium nitrate (30 kg N) and urea-NH 4 NO 3 solution (160 kg N). Variation in the N 2 O emissions with time was extremcly high, with flux rates ranging from 0 to 2700 μg m −2 h −1 . The N 2 O fluxes were influenced by soil properties, management practices, and weather. The highest release rates were measured in the winter during thawing of the frozen soil. During the growing season, N 2 O emission was highest after heavy precipitation. No strong relationship was found between N 2 O emission rates and soil factors such as soil temperature, soil moisturc, and soil nitrate content. Annual fluxes of N 2 O from the extensively managed field were 9.4 and 12.9 kg N 2 O-N ha −1 yr −1 for a sandy soil and a clay soil, respectively. Total N 2 O-N losses from the intensively fertilized field amounted to 9.6 kg ha −1 yr −1 for a silty soil with a tendency to waterlogging during wintertime and to 16.8 kg ha −1 yr −1 for a loamy colluvial soil. Up to 46% of the annual N 2 O evolution was emitted during December and January when frost/thaw cycles induced extremely high N 2 O production. The application of urea-NH 4 NO 3 solution significantly increased N 2 O emission rates. Of the 160 kg N applied, 2.9 kg N or 1.8% was lost as N 2 O within a period of 8 weeks. Rates of CH 4 -C uptake varied from 0 to 17 μg m −2 h −1 . Soil temperature correlated positively and soil moisture correlated negatively with the CH 4 consumption. Stepwise multiple linear regression, including these soil factors, explained up to 44% of the variation in CH 4 fluxes. Annual CH 4 -C uptake was rather similar for the intcnsively and extensively managed Eutrochrepts, ranging from 348 to 395 g ha −1 . Significantly higher CH 4 -C consumption of 567 g ha −1 yr −1 occurred in the colluvial soil (Typic Udifluvent). N fertilizers had no effect on the CH 4 flux rates.
Walker circulation and tropical upper tropospheric water vapor

Maps of the boundary layer divergent wind component derived from velocity potential for two 35-day periods in 1991 and 1994 exhibit a pattern of convergence in the lower levels in the tropical western Pacific, following the Sun between hemispheres, and divergence in the eastern Pacific, these two features agreeing with schematics of the Walker circulation. Vertical motion maps show rising motion in the western Pacific and sinking motion in the eastern Pacific; water vapor maps derived from the microwave limb sounder on the Upper Atmosphere Research Satellite show a similar picture with moist plumes evident at 215 hPa in rising regions and dryness in sinking regions. While these three indicators of vertical motion are internally consistent and fit with accepted views of the Walker circulation, it is shown that there is not equally clear evidence that the eastern and western regions are directly linked by horizontal motions, particularly in the upper troposphere. Mass flux studies based on the divergent winds show that the southeastern Pacific anticyclonic region is fed by upper tropospheric inflow from all sides; in October 1991 the inflow from the west, east, south, and north contributed almost equally, while in February 1994 the inflow from the west was the largest contribution, but flow across the eastern and southern boundaries was also important. The water vapor maps suggest that a substantial fraction of air in the upper troposphere to the wrest of South America originates over the continent. Lidar measurements of cirrus show good evidence of diverging flow into the northern hemisphere from the rising motion in the west Pacific near 10°S during February 1994. The situation in the southeastern Pacific cell in October 1991 is somewhat analogous to that in the northwestern Pacific cell in February 1994 in that flow from a nearby landmass is entrained into the circulation. From daily water vapor maps coupled with potential voracity maps and cross sections, it is suggested that direct exchange between the stratosphere and the troposphere in the form of almost vertical plumes may occur in subsiding regions in the tropics.
An assessment of the absolute accuracy of the Atmospheric Infrared Sounder v5 precipitable water vapor product at tropical, midlatitude, and arctic ground-truth sites: September 2002

[1] The Atmospheric Infrared Sounder (AIRS) is the first of a series of satellite sensors that exploit high spectral resolution and broad spectral coverage of the midinfrared to improve the retrieval accuracy of passive infrared sounding. The AIRS atmospheric retrieval goals are to obtain 1 K accuracy for 1 km layers below 100 mb for temperature and 10% for 2 km layers for water vapor in clear and most cloud conditions. The AIRS total column precipitable water vapor (PWV) is obtained by integrating the vertical profile of water vapor mixing ratio derived from cloud-cleared radiances. The accuracy goal of the AIRS PWV product is 5%. This paper provides a validation of the AIRS PWV product at three distinct climate sites over the nearly full range of total water amounts observed on Earth (between 0.1 and 6.5 cm). Six years (September 2002 to August 2008) of AIRS v5 retrievals of PWV are evaluated against ground-based microwave radiometer (MWR) data at three Department of Energy Atmospheric Radiation Measurement program (ARM) sites. The accuracy of the MWR PWV retrieval is estimated to be between 1% and 3%. This study shows that the agreement between the MWR and AIRS retrievals of PWV is within 5% at all three ARM climate sites for most conditions. The notable exceptions are (1) very dry cases (PWV 1 cm, where AIRS is too dry by about 10%. The moist bias for low water amounts (usually observed during the winter) over land could be a surface emissivity–related error since very little bias is seen at the ARM Arctic site for similar water amounts. The cause of the dry bias at nighttime over land for moderate water amounts is not determined by this study. However, a spatial map of the diurnal bias in monthly AIRS water amount suggests that this effect is related to meteorological conditions in the U. S. Great Plains, which in the summertime is characterized by a moist boundary layer. The diurnal error in AIRS PWV at the SGP site seen with respect to the MWR data are confirmed by PWV amounts derived from a coincident ground-based GPS receiver.
Evidence for an ice‐free Wrangel Island, northeast Siberia during the Last Glacial Maximum

10Be and 26Al surface exposure ages from 22 tors and bedrock samples from Wrangel Island, northeast Siberia, indicate that the East Siberian and Chukchi shelves were ice‐free during the Last Glacial Maximum (LGM). The paucity of glacial landforms and deposits, the absence of erratics and the presence of radiocarbon dates on plant and mammal fossils that span the LGM suggest that Wrangel Island also remained free of extensive glacial ice during the LGM. The lack of moisture due to the continental climate on the emergent Bering Land Bridge is the most likely reason for limited ice in this part of the Arctic. Alternative interpretations regarding the age and origin of ‘glaciogenic’ bedforms on the Chukchi shelf should be considered.
Infra‐red FTS measurements of CH4, N2O, O3, HNO3, HCl, CFC‐11 and CFC‐12 from the MANTRA balloon campaign

Abstract The Middle Atmosphere Nitrogen TRend Assessment (MANTRA) campaign is intended to address the question of whether possible changes in the mid‐latitude nitrogen budget can account for discrepancies between predicted and observed ozone loss at these latitudes. In addition, MANTRA seeks to establish consistency between old and new measurement techniques. We report here the results of infra‐red spectral measurements made with a high resolution Fourier Transform Spectrometer (FTS) during the August 1998 MANTRA flight. Vertical mixing ratio profiles of methane, nitrous oxide, ozone, nitric acid, hydrogen chloride, CFC‐11 and CFC‐12 are presented. The error estimates on the retrieved values are larger than typical for this type of measurement, due mostly to instrument problems that occurred during flight. In addition, the CFC values are larger than expected. Possible reasons for this are discussed.
Laboratory investigation of wave run-up caused by landslides in dam reservoirs

Waves generated by underwater landslides are studied in a physical laboratory model. A total of 102 laboratory tests were carried out. The experimental data measured generation, propagation and run-up of water waves. A wide range of effective parameters are considered in the experimental tests. Based on laboratory data, an empirical method is presented for prediction of impulse wave run-up caused by an underwater landslide in a dam reservoir. This method is developed using only the information about landslide geometry, initial submergence, water depth and sidewall slopes in the dam reservoir. The presented equation is successfully verified using laboratory-based and analytical equations from the literature. The equation is also applied in a real case study for a dam reservoir in Iran in which the impulse wave characteristics are available, and good reliability is obtained.
Bacteria transport in an unsaturated porous media: incorporation of air–water interface area model into transport modelling

The bacterial transport model into which the air–water interface (AWI) area model is incorporated is developed in this study. At the outset, the AWI area models are analysed to determine the appropriate model. In the analysis, three models are evaluated with the previously reported experimental data, and the modified form of the Niemet et al. (2002) model is selected as an appropriate AWI area model, which is then combined into the transport model. The bacterial transport model is used to fit the bacterial breakthrough data in an unsaturated porous media from the literature, and the fitting results show that the model matches well with the observed data at three different air contents by varying the specific AWI area. On the basis of the sorption‐related parameters determined from the literature, simulations are performed to examine bacterial transport in three different soils under unsaturated and transient flow conditions. The results illustrate that bacteria can travel to different depths in unsaturated soils depending on the soil type and water content. Even if the predictive model presented in this study is not comprehensive, it will help to understand bacterial transport behaviour in an unsaturated porous media. Copyright © 2007 John Wiley & Sons, Ltd.
The impact of climate and reservoirs on longitudinal riverine carbon fluxes from two major watersheds in the Central and Intermontane West

A nested sampling network on the Colorado (CR) and Missouri Rivers (MR) provided data to assess impacts of large‐scale reservoir systems and climate on carbon export. The Load Estimator (LOADEST) model was used to estimate both dissolved inorganic and organic carbon (DIC and DOC) fluxes for a total of 22 sites along the main stems of the CR and MR. Both the upper CR and MR DIC and DOC fluxes increased longitudinally, but the lower CR fluxes decreased while the lower MRs continued to increase. We examined multiple factors through space and time that help explain these flux patterns. Seasonal variability in precipitation and temperature, along with site‐level concentration versus discharge relationships proved to be significant factors explaining much of the difference among sites located below reservoirs as compared to sites located in more free‐flowing segments of the river. The characterization of variability in carbon exports over space and time provides a basis for understanding carbon cycling and transport within river basins affected by large reservoir systems, particular in arid‐to semi‐arid ecosystems.
Haemoprotozoan Disease Classification in Cattle using Portable Device

: This survey aims to automate the process of identification and diagnosis of Haemoprotozoan diseases in cattle, using machine learning algorithms to build a model from a dataset of images and diagnoses collected from local labs. The project focuses on three significant Haemoprotozoan diseases that pose a significant risk to cattle all across India: Anaplasmosis, Babesiosis, and Theileriosis. The model is designed to run on a client-server web application, where a picture of the bloodstream sample is sent to the server, which then returns two parameters specifying whether the diagnosis is positive or negative, and the type of disease. This could significantly reduce mortality rates by making the process cheaper and faster. The model will be tested and evaluated several times in the training and testing modules. The evaluation process will be based on the model's accuracy, as well as other factors such as the model's speed and cost-effectiveness. The outcomes are then differentiated from the existing models already in use, to inspect the accuracy and implementation of the model. The final model will be deployed in the client-server web application.