The spatio-temporal variability of river processes is governed by the balance between basin scale sediment supply and channel transport capacity. This balance is being altered by rampant sediment mining from the rivers which results in channel alteration and loss of physical habitat. The sediment mining guidelines are mostly based on empirical approaches and do not consider the spatio-temporal variability of river processes. This study includes hydrologic and geomorphic analysis to understand sediment dynamics and to suggest guidelines for sediment mining. The study was carried out in the 1312 km long Narmada River basin, Central India using hydrological data (1987-2015), SRTM DEM and LULC data. We identified the major aggrading river reaches (100s of km long) on the basis of reach scale sediment mass balance analysis. These reaches are dominantly aggrading at the rate of ~50,000 tons/km/yr. Sediment yield values were used to identify major erosion hot spots in the river basin and its contribution to spatial variability in aggradation-degradation processes in the river channel. This spatial variability within channel was also ascertained through stream power and sediment supply relationship. Further, temporal variability in channel processes was observed in the aggrading reaches. This variability is mostly governed by sediment concentration. Higher sediment concentration (~1.5 g/l) in a given month may change degrading reaches into aggrading reaches. Spatial variability within aggrading reaches and sediment contribution from different sub-basins was further assessed through application of semi-distributed process based Soil and Water Assessment Tool (SWAT). SWAT-CUP yielded good calibration results (~ 40% of the measured data bracketed under the 95PPU envelope, for discharge and sediment load). SWAT was found to be suitable to analyze sediment yield distribution at HRU scale in the Narmada River basin, except for smaller and steeper subbasins where hillslope processes dominate. Further, spatial variability within these reaches was identified by analysis of bar dynamics. Satellite data based change detection analysis was used to identify aggrading channel bars. These bars may be focused for sand mining operations within the aggrading reaches, although limited to ~20% change in the sediment bar area.

We re-examine data from a deep earthquake beneath NE Taiwan as recorded by the Formosa Array to explain mechanisms of a significant later P phase. For 2D simulations, we set up an initial velocity structure with (A) a high Vp anomaly in the mantle wedge above Ryukyu subduction, and (B) a slightly high Vp Eurasian lithosphere to the west with a sub-vertical boundary – based on results of tomographic studies. We conclude that (1) the small-amplitude first P phase is attributed to the energies radiated near the nodal point of the focal mechanism and propagated through (A), (2) those of the significant later P phase are analogous to a head wave that propagates and generates spherical waves along (B) that are received at the surface. Accordingly, stations of zero delay time between the first and second P provide a first-ever portrayal of the Eurasian lithosphere boundary by waveform constraints.

The frequency of major solar eruptions, and their space weather impacts at earth vary with the cycle of solar activity but large amplitude events can occur at any time. Each solar cycle has a distinct amplitude and duration so that the solar cycle dependent frequency of rare, extreme space weather events is challenging to quantify. By constructing the analytic signal of daily sunspot numbers since 1818 we construct a new solar cycle phase clock which maps each of the last 18 solar cycles onto a single time-base. This clock orders solar coronal activity and extremes of the aa index, which tracks geomagnetic storms at the earth’s surface over the last 14 solar cycles. We identify and quantify the occurrence times of a geomagnetically quiet solar cycle interval of ~4.4 years (~2 pi/5 phase or 40% of the cycle) in extent centered on solar minimum within which only two severe (aa>300nT) and one extreme (aa>500nT) geomagnetic storms occurred since 1868. The solar cycle modulation of activity is such that 1-3% of severe (aa>300nT) geomagnetic storms and 4-6% of C, M and X class solar flares occurred in the solar cycle quiet phase. Terminators of solar EUV bright point activity indicate the end of this quiet interval and the ‘switch on’ of increased frequency of solar flares and geomagnetic storms. This provides quantitative support to planning resilience against space weather impacts since only a few percent of all severe storms occur in this quiet interval and its start and end are forecast-able.

The power-law relationship has been regarded as the fundamental description of the size distribution from large-scale-earthquake to small-scale-laboratory rock ruptures. However, deviation from the power-law relationship has often been reported, especially when the amplitude distribution is used for -value estimation in rock acoustic emission testing, the effect of attenuation should be considered. Here, we perform a detailed analysis on the deviation of the size distribution from a power law and prove that the cumulative frequency distribution will inevitably result in deviation from the power law. We also discuss modification of the attenuation on the doubly truncated size distribution from a more general perspective. We find that in a certain interval, the attenuation will not modify the size distribution and the -value is theoretically verified to be unchanged. Based on these discussions, we propose a new -value estimation procedure for rock acoustic emission testing and apply it to a dilation rupturing test, the procedure exhibits good performance.

Old abandoned coal working create major hazards in the form of subsidence of the coalfields. To avoid such hazards, there is need to detect these cavities prior to start of deeper seam mining. There are number of geophysical techniques available for detecting subsurface cavity. High-resolution seismic survey is one such technique which provides accurate results as compared to others. Usually, most of the seismic processing and interpretation of these cavity detection was performed based on stacked data only. To understand these signatures more precisely, in our study, an attempt has been made to image these cavities with the help of Reverse Time Migration (RTM) combined with Full Waveform Inversion (FWI). RTM mostly used for hydrocarbon exploration targets with low central frequency as source. Application of this method to shallow subsurface exploration is still in research stage. Like the same way for velocity model updating, FWI gives mostly appropriate optimization results as compare to other techniques, but it also has the limitation to application of low frequency only. In this paper we first develop a 2D realistic Water Filled Cavity (WFC) model with a work flow of RTM combined with FWI in a high-frequency Ricker source wavelet as 100 Hz. In order to provide a velocity model with high accuracy for RTM, we apply FWI to estimate the subsurface velocity by considering an initial smooth velocity model with addition of 30 % Gaussian noise. The conventional RTM fails to image the cavities and yield a large amount of low frequency back scattered noise at shallow depth during the time of cross correlation due to time/space lag. To avoid these situation, we introduced an automatic shift operator at the time of imaging condition that operates automatically both in time or space. It leads to reduce the lag and improve the results by minimizing the noises at shallow subsurface. By comparing both the results it is observed that most of the noises in the migrated section of conventional method were eliminated by the improved form of RTM with the help of FWI velocity model estimation.

The most important task of the seabed electromagnetic data acquisition station is to discretize and sample the marine geophysical field signal according to the set working parameters. The system controller of the station generates the working sequence of data acquisition according to the system clock. In addition, the system needs to record the underwater real clock of the corresponding collected data for later data processing and inversion. The system real-time clock is generated by the counting and accumulation of second pulse (SP) signal, and the accuracy of SP depends on the clock stability of system clock source, such as atomic clock or crystal oscillator. The change of ambient temperature is the main factor affecting the clock accuracy of the system. When the ambient temperature changes, the output frequency of the clock source also changes, which leads to the advance or delay of the counting overflow point of the pulse counter relative to the standard clock. If the temperature characteristic of the clock source is measured first, then the overflow count of the pulse counter can be adjusted, the influence of temperature change on the output frequency can be compensated, as a result, the clock synchronization accuracy can be improved. However, when the output frequency of the clock source is low, the method of compensating the output frequency simply by changing the preset number of the counter will produce large errors. In this case, it is necessary to accurately adjust the output frequency and phase. Therefore, we use direct digital synthesizer (DDS) to realize the above assumption. In this process, the output frequency error curve of the clock source is fitted according to the discrete data point measured in the temperature characteristic experiment, then the curve is stored in the system memory area in the form of look-up table. Micro controller (MCU) of the system performs curve interpolation calculation according to real-time temperature and generates frequency control word (FCW). DDS adjusts the output frequency and phase of the clock source according to the FCW, Finally, the corrected clock is output after processing such as amplification and filtering.

The article proposes a straightforward Kalman filter-based method for computationally efficient ionospheric electron density multi-instrument imaging. The approach uses direct ionospheric measurements, such as ionosondes, and general physical assumptions to estimate the uncertainty associated with the previous reconstructed time step. Therefore the method does not require any electron density model of the ionosphere as a background. The uncertainty is represented by an inverse covariance matrix constructed with Gaussian Markov random fields, allowing the problem to be solved numerically with relatively high resolution. The experiments utilise measurements from dense ground-based GNSS and low Earth orbit beacon satellite receiver networks as well as ionosondes. A synthetic simulation study and real data validation with a specific EISCAT incoherent scatter radar measurement campaign is carried out over Northern European sector. The method can be controlled using parameters with probabilistic and physically realistic interpretations that can be applied to both simulated and real-world data. The results show that the approach is feasible for near real-time regional ionospheric imaging. Especially, the method can be seen as an expansion to local profile measurements field of view, but with sufficient measurement coverage, it also provides information further away from the specific instrument.

Soil water flow and physical quality as influenced by soil water retention curve fitting methods

The traditional method of measuring the lettuce height is a manual measurement with instruments, which is greatly affected by human error.At present, researchers have proposed to use color cameras to obtain RGB images of lettuce, and to obtain the height of lettuce from the images. However, these tasks usually require camera calibration or a reference object with a known height, which is somewhat restrictive. Considering that deep neural networks have a powerful ability to feature extraction and expression, without camera calibration and reference objects, we try to use four networks of image recognition to explore the effect of deep learning on abstracting the lettuce height from RGB images. On the test set, including 80 images and height from 0.9 cm to 7.5 cm, we achieve a good result with a mean absolute error of 1.22 mm.

The nonthermal continuum radiation (NTC) beaming angle is computed over the entire Van Allen Probes A mission when the spacecraft was in the dawn sector. The conditions in the dawn sector are favorable for the wave vector to lie near/in the spacecraft’s spin plan allowing a favorable estimate of the beaming angle, and the dawn sector is also advantageous in that previous studies show NTC occurrence to peak in this sector. We found that scatter plots, over the entire mission, of beaming angle versus magnetic latitude form a distinct inverted V pattern, with the apex at/near the magnetic equator. This pattern was sharpest for frequencies (f) ≲ 100 kHz. Using the NTC beaming formula from LMCT, we show that such an inverted V pattern is expected due to the large variation in the plasmapause location over the entire mission. The theoretical derived pattern qualitatively reproduces the observed pattern but not quantitatively. The lack of quantitative agreement is discussed and is attributed to several factors, one factor is off centered emissions from the radio window. The qualitative agreement strongly supports LMCT as being the dominant mechanism generating NTC for f ≲ 100 kHz. For f ≳ 100 kHz the inverted V pattern becomes less distinct, and strong near equatorial beaming is observed. After considering contamination of our selections by left-handed polarized AKR, our study suggests that besides LMCT another unidentified NTC generation mechanism becomes important for f ≳ 100 kHz.

This empirical research analyses a unique vintage photographic plate that confirms the location of a lost Wonder of the World, the Pink and White Terraces. Their location has been debated since 1886 when they were buried in a volcanic eruption. The paper develops a Parallax Effect methodology with a Skyline Gauge to test all 1886-2024 claims to the White Terrace location. Methods include photo-interpretation, photogrammetric optics, topography and forensic cartography. The results show nearly all claims have significant errors. The Gauge location is consistent with the coordinates provided by the 1859 Hochstetter Survey, the Hochstetter Paradigm and the early claimants.

This study provides insights on the composition and variability of atmospheric aerosols over the United Arab Emirates (UAE) by analyzing the atmospheric conditions together with 14-years (2006-2019) of aerosol optical depth (AOD) retrieved from CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellite, and 7 years of AOD measured from the ground-based Aerosol Robotic Network. We found that mineral dust is the most prevailing aerosol subtype. In addition, polluted dust and polluted continental aerosols are observed mostly in the cold season. The AOD is higher in spring and summer, when the atmospheric conditions are more favourable to the occurrence of dust events. Moreover, there is another peak in winter associated with dust storms triggered by mid-latitude baroclinic systems. In summer’s daytime, extinction coefficients in excess of 0.2 km-1 are observed up to 3-4 km above the surface, as a result of the warmer and windier conditions. In the cold season and at night, the dust layers are confined to the lower atmosphere below 2 km. On a climatological time scale, we found that the AOD over the UAE has been decreasing since 2009, possibly due to the increasing trend in precipitation and changes in land use. This study highlights the large contribution of dust aerosols to the total aerosol load over the UAE and stresses on the need to account for mineral dust aerosols in climate-air pollution related studies as well as weather and air quality forecasts.

NASA’s Capacity Building Program (CBP) works to empower communities around the globe to use Earth observation data and products in their decision making. Working through program and element activities, CBP developed a theoretical framework for engagement focused around user needs which identifies the appropriate path for engagement based on geography, discipline, data needs and availability, depth of support required, partnerships involved, length of engagement, and desired outcomes. These decision factors would determine which CBP element would take on the effort – ARSET, DEVELOP, or SERVIR, and which approach would be implemented – trainings or co-development. Each approach offers participants different benefits and leads to outcomes that fall on a spectrum from increased awareness to sustained use of Earth observations. However, implementation of this framework across multiple programs with differing constraints has been challenging. This presentation will highlight the CBP framework and its user-centric approach, capacity building methods and incentives, metrics and tracking indicators, challenges, and lessons learned.

GeoHealth as a research paradigm offers the opportunity to re-evaluate common research engagement models and science training practices. GeoHealth challenges are often wicked problems that require both transdisciplinary approaches and the establishment of intimate and long term partnerships with a range of community members. We examine four common modes of community engagement and explore how research projects are launched, who has the power in these relationships, and how projects evolve to become truly transformative for everyone involved.

Social Learning contributes as a guiding proposal for the joint intervention of the local actors and dissemination of methodologies and collaborative activities in socioenvironmental diagnoses. Its principles are active involvement, consultation and public access to participation. Several participatory tools have been developed and have been applied within the principles of Social Learning, such as local socioenvironmental agendas, action research, role playing; world café, participatory monitoring of the streams and socioenvironmental mapping. This article presents the last one applied in different contexts and with different groups of social actors, always aiming to elaborate a participatory diagnosis of the place and reality to identify the wicked problems. Socioenvironmental mapping is a didactic-pedagogical resource used to reflect and rethink about the place. It contributes to elaborate a diagnosis of the local reality and it subsidizes the reflection on the forms of the land use and occupation and its implications for the quality of life of its inhabitants, fostering discussions, possibilities of actions to solve problems and conflicts to improve the quality of life in communities. The map is a product of collective and collaborative construction of the participants. It contributes to transform information into knowledge and establish a bridge between scientific and local knowledge. Consider the following procedures: a) the reality in which the individual lives and how he deals with his immediate environment and his understanding of it, as a starting point; b) the possibility of re-elaborating the individual’s initial understanding of his / her place; c) the way to the development of different types of knowledge for the construction of more elaborate and more critical knowledge. We have applied this methodology with teaching formation, social control and conservation area with positive results of empowering the communities.

Exploring the connections between injection wells and seismic migration patterns is key to understanding processes controlling growth of fluid-injection induced seismicity. Numerous seismic clusters in Oklahoma have been associated with wastewater disposal operations, providing a unique opportunity to investigate migration directions of each cluster with respect to the injection-well locations. We introduce new directivity migration parameters to identify and quantify lateral migration toward or away from the injection wells. We take into account cumulative volume and injection rate from multiple injection wells. Our results suggest a relationship between migration patterns and the cluster-well distances, and unclear relationship with injected volume and equivalent magnitudes. Migration away from injection wells is found for distances shorter than 5-13 km, while an opposite migration towards the wells is observed for larger distances, suggesting an increasing influence of poroelastic stress changes. This finding is more stable when considering cumulative injected volume instead of injection rate.

Coalbed Methane is an attractive source of energy to mitigate the growing energy demand of India. It is often abbreviated as unconventional source of energy. In this paper two bore hole samples (J/01 & J/02) were collected and characterized for the isotherm studies to know the sorption capacity of the coal. Pure gas isotherm was constructed based on the manomateric method. Pure gas isotherm was constructed in indigenously fabricated setup. Langmuir model was used for the prediction of sorption capacity at particular pressure. Langmuir constants (PL & VL) were calculated using regression analysis. It was found that volume wise CO2 has 2.09 to 2.75 times more adsorption capacity than coal.Once pure gas isotherm was drawn and PL and VL was calculated. Langmuir constants were given as follows: CH4 -VL (scf/ton) of J/01 and J/02 are 227.27 and 454.55 respectively CH4 -PL (psi) of J/01 and J/02 are 128.54 and 173.68 CO2-VL (scf/ton) of J/01 and J/02 are 476.19 1250 respectively CO2-PL(psi) of J/01 and J/02 are 133.33 596.13 Binary mixture of CH4 and CO2 was modelled at different gas mixtures and at pressure of 2000 psi. Multicomponent iterative model (MIA) was proposed using Newton Raphson iteration to study the co adsorption isotherm of CH4 and CO2 at different binary mixtures. It was found that one CO2 mole fraction increases in gas phase. For sample J/01 Enhanced Coalbed Methane (ECBM) recovery will occur after 27.4 % of CO2 in gas phase while ECBM recovery will occur after 13.03% of CO2 in gas phase. Pure component isotherm and co adsorption isotherm is given in figure 1 & 2.

Atmospheric rivers (ARs) are responsible for the vast majority (approximately 88%) of flood damage in the Western U.S, an annual average of USD$1.1 billion. Here, using historical flood insurance data, we investigate the genesis characteristics of damaging ARs in the Western U.S. ARs exceeding USD$20 million in damage (90th percentile), are shown to travel further across the Pacific Ocean, with median genesis locations 8° to 27° longitude further westward compared to typical ARs. Identifying regions of preferential genesis of damaging ARs elicit important implications for AR observation campaigns, highlighting distant regions not currently considered for AR reconnaissance. The genesis of damaging ARs is associated with elevated upper-level zonal wind speeds along with deeper cyclonic anomalies, most pronounced for Washington and Oregon ARs. Linking AR dynamics and lifecycle characteristics to economic damage provides an opportunity for impact-based forecasting of ARs prior to landfall, supporting efforts to mitigate extreme flood damages.