Data Mining approach to identify PFZ(Potential Fishing Zone) using Oceanographic Data

Oceanographic factors (biological, physical and chemical) and fisherman’s expertise are the two basic ways for determining potential fishing zones. There are many disadvantages with this approach when it comes to determining the exact potential fishing zones(PFZs) spatially and temporally.In our proposed framework, we have come up with a data mining approach for identifying PFZ in Indian ocean. We procured spatio -temporal images from Copernicus Online Data Access (CODA) and then extracted characteristics, Sea Surface Temperature (SST) and Sea Surface Chlorophyll(SSC) with the help of Sentinel Application Platform(SNAP).The results of this extraction method were used as Training data in the classification process, which was then used to PFZs. During the classification process, we utilized ensemble learning approach consists of different algorithms such as KNN, Naïve-Bayes, KNN classifier-5, KNN-classifier-10, Support Vector Machine (SVM), logistic regression, decision tree. The result gave an average accuracy of 80%, which showed that the proposed framework can be used effectively to determine PFZs.To validate the framework, we followed the process of cross-validation with the labelled data. The results showed that the proposed data mining framework predicted the correct values

Quantifying the effects of delisting wolves after the first state began lethal management

Predators and their protection are controversial worldwide. Gray wolves, Canis lupus, lost U.S. federal protection (delisting) and the State of Wisconsin began lethal management first among all states and tribes that regained authority over wolves. Here we evaluated the initial success of reaching the state’s explicit objective, “…to allow for a sustainable harvest that neither increases nor decreases the state’s wolf population…” We used official state figures for hunter-killed wolves, population estimates from April 2017–2020, and the latest peer-reviewed model of individual wolf survival to estimate additional deaths resulting from federal delisting. More than half of the additional deaths were predicted to be cryptic poaching under the assumption that this period resembled past periods of liberalized wolf-killing in Wisconsin. We used a precautionary approach to construct three conservative scenarios to predict the current status of this wolf population and a minimum estimate of population decline since April 2020. From our scenarios that vary in growth rates and additional mortality estimates, we expect a maximum of 695–751 wolves to be alive in Wisconsin by 15 April 2021, a minimum 27–33% decline in the preceding 12 months. This contradicts the state expectation of no change in the population size. We draw a conclusion about the adequacy of regulatory mechanisms under state control of wolves and discuss the particular governance conditions met in Wisconsin. We recommend greater rigor and independent review of the science used by agencies to plan wolf hunting quotas and methods. We recommend clearer division of duties between state wildlife agencies, legislatures, and courts. We recommend federal governments reconsider the practice of sudden deregulation of wolf management and instead recommend they consider protecting predators as non-game or transition more slowly to subnational authority, to avoid the need for emergency relisting

ANALYSIS OF PERFORMANCE OF FLAT EARTH PHASE REMOVAL METHODS

Interferometric synthetic aperture radar (InSAR) has been widely used in remote sensing field, which can reflect actual topographic trend or possible surface deformation. Due to the orbit attitude influence, the flat-earth phase usually causes the interferogram dense and difficult to be used in further procedures. Before phase unwrapping, interferogram must be flattened to derive accurate topographic or deformation information. In this paper, analysis of performance of two methods of flat-earth removal is done. First method uses imaging geometry and second method uses precise orbital information. Further, 3-degree, 5-degree and 7-degree polynomials are fitted in the method using precise orbital information. Validation is done both visually and empirically using entropy as the evaluation index

Frontshear and backshear instabilities of the mean longshore current

An analytical model based on Bowen and Holman [1989] is used to prove the existence of instabilities due to the presence of a second extremum of the background vorticity at the front side of the longshore current. The growth rate of the so-called frontshear waves depends primarily upon the frontshear but also upon the backshear and the maximum and the width of the current. Depending on the values of these parameters, either the frontshear or the backshear instabilities may dominate. Both types of waves have a cross-shore extension of the order of the width of the current, but the frontshear modes are localized closer to the coast than are the backshear modes. Moreover, under certain conditions both unstable waves have similar growth rates with close wave numbers and angular frequencies, leading to the possibility of having modulated shear waves in the alongshore direction. Numerical analysis performed on realistic current profiles confirm the behavior anticipated by the analytical model. The theory has been applied to a current profile fitted to data measured during the 1980 Nearshore Sediment Transport Studies experiment at Leadbetter Beach that has an extremum of background vorticity at the front side of the current. In this case and in agreement with field observations, the model predicts instability, whereas the theory based only on backshear instability fai led to do so

Experimental study of nearshore dynamics on a barred beach with rip channels

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95201/1/jgrc8777.pd

Wave-driven setup and alongshore flows observed onshore of a submarine canyon

Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 113 (2008): C07025, doi:10.1029/2007JC004514.The effect of alongshore variations in the incident wavefield on wave-driven setup and on alongshore flows in the surfzone is investigated using observations collected onshore of a submarine canyon. Wave heights and radiation stresses at the outer edge of the surfzone (water depth ≈2.5 m) varied by up to a factor of 4 and 16, respectively, over a 450 m alongshore distance, resulting in setup variations as large as 0.1 m along the shoreline (water depth ≈0.3 m). Even with this strong alongshore variability, wave-driven setup was dominated by the cross-shore gradient of the wave radiation stress, and setup observed in the surfzone is predicted well by a one-dimensional cross-shore momentum balance. Both cross-shore radiation stress gradients and alongshore setup gradients contributed to the alongshore flows observed in the inner surfzone when alongshore gradients in offshore wave heights were large, and a simplified alongshore momentum balance suggests that the large [O(1 kg/(s2 m)] observed setup-induced pressure gradients can drive strong [O(1 m/s)] alongshore currents.Funding was provided by the Office of Naval Research and the National Science Foundation

Mount Etna as a terrestrial laboratory to investigate recent volcanic activity on Venus by future missions:A comparison with Idunn Mons, Venus

The recently selected missions to Venus have opened a new era for the exploration of this planet. These missions will provide information about the chemistry of the atmosphere, the geomorphology, local-to-regional surface composition, and the rheology of the interior. One key scientific question to be addressed by these future missions is whether Venus remains volcanically active, and if so, how its volcanism is currently evolving. Hence, it is fundamental to analyze appropriate terrestrial analog sites for the study of possibly active volcanism on Venus. To this regard, we propose Mount Etna - one of the most active and monitored volcanoes on Earth - as a suitable terrestrial laboratory for remote and in-situ investigations to be performed by future missions to Venus. Being characterized by both effusive and explosive volcanic products, Mount Etna offers the opportunity to analyze multiple eruptive styles, both monitoring active volcanism and identifying the possible occurrence of pyroclastic activity on Venus. We directly compare Mount Etna with Idunn Mons, one of the most promising potentially active volcanoes of Venus. Despite the two structures show a different topography, they also show some interesting points of comparison, and in particular: a) comparable morpho-structural setting, since both volcanoes interact with a rift zone, and b) morphologically similar volcanic fields around both Mount Etna and Idunn Mons. Given its ease of access, we also propose Mount Etna as an analog site for laboratory spectroscopic studies to identify the signatures of unaltered volcanic deposits on Venus

Household pre-purchase practices and online grocery shopping:e-grocery pre-purchase trajectories

This paper explores household pre-purchase practices and their mediation by information and communications technologies (ICTs), specifically online grocery shopping. Drawing on practice theory, the impacts of ICTs on household grocery shopping behavior are conceptualized, and the concept of “front-loading” is introduced. Emerging themes generated from 31 semi-structured interviews conducted via Skype with Turkish consumers focusing on their experiences of online grocery practices are presented. To this end, the contribution of this paper is twofold. First, an understanding of the domestication of online grocery shopping and its affect on the dynamics of household decision making, information sharing, and responsibilities of tasks before the actual act of online shopping is developed. Second, how such pre-purchase practices undertaken by consumers act as a catalyst of change at the industry level is appraised

Introducing the “analogs for Venus’ geologically recent surfaces” initiative: an opportunity for identifying and analyzing recently active volcano-tectonic areas of Venus trough a comparative study with terrestrial analogs

Several missions to Venus have been recently selected for launch [1–6], opening a new era for the exploration of the planet. One of the key questions that the future missions need to address is whether Venus is presently volcanically active [7–15]. Studying areas of active volcanism and tectonism on Venus is crucial to reveal clues about the geologic past of the planet, as well as provide information about the volatile content of its interior and the formation of its dense atmosphere. The “Analogsfor VENus’ GEologically Recent Surfaces” (AVENGERS) initiative aims to build a comprehensive database of terrestrial analog sites for the comparative study of recent and possibly on- going volcanic activity on Venus. Besides its scientific relevance, the AVENG- ERS initiative also acts as a bridge for international scientific collaboration, including the leadership and/or team members from the currently selected missions to Venus

Wave-current interaction in Willapa Bay

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 116 (2011): C12014, doi:10.1029/2011JC007387.This paper describes the importance of wave-current interaction in an inlet-estuary system. The three-dimensional, fully coupled, Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system was applied in Willapa Bay (Washington State) from 22 to 29 October 1998 that included a large storm event. To represent the interaction between waves and currents, the vortex-force method was used. Model results were compared with water elevations, currents, and wave measurements obtained by the U.S. Army Corp of Engineers. In general, a good agreement between field data and computed results was achieved, although some discrepancies were also observed in regard to wave peak directions in the most upstream station. Several numerical experiments that considered different forcing terms were run in order to identify the effects of each wind, tide, and wave-current interaction process. Comparison of the horizontal momentum balances results identified that wave-breaking-induced acceleration is one of the leading terms in the inlet area. The enhancement of the apparent bed roughness caused by waves also affected the values and distribution of the bottom shear stress. The pressure gradient showed significant changes with respect to the pure tidal case. During storm conditions the momentum balance in the inlet shares the characteristics of tidal-dominated and wave-dominated surf zone environments. The changes in the momentum balance caused by waves were manifested both in water level and current variations. The most relevant effect on hydrodynamics was a wave-induced setup in the inner part of the estuary.Primary funding for this study was furnished by the U.S. Geological Survey, Coastal and Marine Geology Program, under the Carolinas Coastal Change Processes Project.2012-06-1