Understanding of Atmospheric Systems with Efficient Numerical Methods for Observation and Prediction Online Course https://giladjames.com Section: Tropical Cyclone Center Determination Algorithm by Texture and Gradient of Infrared Satellite Image Lesson: Experimental group of eye TC center location Introduction Tropical cyclone (TC) is one of the most serious natural disasters in the world. Satellite remote sensing technology can not only observe the whole situation but also the structural characteristics and center information of a TC. It is the current main method of the TC center location. Dvorak technique (DT) is widely used to TC center location. DT, which was proposed by in the 1970s was the most important method for TC analysis in the world. Nowadays, based on the DT, advanced Dvorak technologies were developed to determine the TC center location. Li et al. put forward a new artificial intelligence algorithm for the eye TC center location. First, the image segmentation technique was used to extract the TC cloud features. And then, the mathematic morphology opening operation and the filling operation are used to obtain the contour of the TC eye. The gravity calculation method is applied to locate the TC center. Comparing the data to the Central Meteorological Observatory of China, the experimental results show that the deviation is smaller. Li et al. proposed an improved genetic algorithm to determine the TC center location. The theoretical analysis and experimental results show that this method is reasonable and effective. Yang et al. combined pattern matching with the vector field analysis to determine the TC center position. The proposed method is very efficient for the TCs, which have clear spiral structure. Fan et al. used 85 GHz vertical polarization channels in specail sensor microwave/imager (SSM/I) for TC center location. According to the distributed characteristics of brightness and temperature, the TC of its band is analyzed and classified. The average gap of the best route in the test results of TC is smaller. Wei et al. presented a novel spiral band model to automatically locate the TC center. And particle swarm optimization was used to optimize the model parameters. Experimental results show that this model can achieve the best average error in both latitude and longitude in comparison with the best track data. Zhang et al. proposed a novel intelligent automatic system framework, which was based on the image process technology to locate the TC center. According to the symmetry shape and spiral movement feature of TC, a rotation matching methodology is used to catch the track of TC. Compared with the data of Shanghai Meteorology Center, experimental results show that this system is efficient and the performance errors are acceptable for practical applications. Zheng et al. established the TC forecast service production system based on geographic information system (GIS) technology and realized the function construction. It had met the requirements of the TC center forecast service production in the Central Meteorological Observatory. Recently, some researchers used deviation angle variance and pattern matching algorithm for TC center detection. Although there are some advantages in the above methods, some defects are existing. The subjectivity of DT is stronger, and the degree of automation is limited. The location effect for the smaller intensity cyclone is poorer. The method based on mathematical morphology is suitable for tropical cyclone whose morphology characteristic can be identified easily. If it is applied to the weak or atypical morphology cyclone, a big deviation will be resulted. Intelligent learning method requires a lot of experimental data and experience accumulation. It is suitable for recognizing the particular structures. Wind field analysis method is applicable to locate the tropical cyclone center, which is weak and whose circulation center is not clear. When the intensity level of tropical cyclone is higher, the center location is not accurate because it is easily affected by the resolution and heavy rain. The temperature/humidity structure retrieval method is also only applied to locate the tropical cyclone center whose intensity is strong. The tempo-spatial movement mat #understanding #of #atmospheric #systems #with #efficient #numerical #methods #for #observation #and #prediction ... https://www.youtube.com/watch?v=y562NWuexHU

Climate Variability Online Course https://giladjames.com Section: Climate Risk Assessment for Water Resources Development in the Niger River Basin Part I: Context and Climate Projections Lesson: Overview of approach and methodological framework - PART 3 Climate Variability. This course is brought to you by Gilad James Mystery School. Learn more at Gilad James.com. Introduction Climate change has emerged as one of the most important challenges of the 21st century. Consequently, a plethora of studies has appeared which focus on adaptation measures for responding to the climate change threat. A cursory review of much of the adaptation literature shows, however, that most of it contains little more than generic recommendations to vaguely defined or specified threats. This situation results from the fact that generally the specific impacts of climate change in specific locations or to specific sectors remain poorly understood and under-investigated. This situation is especially acute in Africa where adaptation strategies are urgently needed. In this lecture, we present the results of a study designed to identify and quantify specific impacts of climate change to the hydro-energy, environmental, and agro-economic sectors in the Niger Basin in West Africa. The Niger River is the second largest river in Africa by discharge volume (5,600 m3/s at Onitsha; 1955-1991) and the third longest (4,100 km). Taking its source on the interior side of the Guinea Daro Massif at an altitude of 1068 meters, the Niger River runs off in a northeasterly direction towards the Niger Inland Delta. At Tossaye (Taoussa, Republic of Mali), the river turns southeast forming the Great Bend and flows on through Niger to Lokoja in Nigeria, where it receives its largest and most important tributary, the Benue River (Fig. 1). From there, the enlarged Niger runs directly south to empty into the Bight of Benin through a network of distributaries in Nigeria’s Terminal Niger Delta. The river’s unusual flow path delineates a drainage basin that is boomerang-shaped and bounded approximately by latitudes 5° N and 22° N and by longitudes 11°30΄ W and 15° E. The Niger Basin’s total drainage area is 2,170,500 km² although 35% (770,500 km2) of the basin lies within the hyper-arid Sahara and contributes no runoff to the Niger River. The Niger Basin cuts across all the major climatic zones of West Africa, including the Guinean or Equatorial forest zone, the Transitional tropical belt, the Sudan Savanna zone, the semi-arid or Sahel savanna belt, and the desert region. Rainfall, temperature, humidity and evaporation all exhibit steep gradients as one moves hinterland from the coast (Fig. 2). The Location of the Niger Basin in West Africa. Source: BRLi, 2007. The climatic characteristics of the Niger Basin. The panel on the top left shows the distribution of annual average precipitation, the panel on the top right shows the basin demarcated into active and inactive parts. Also shown is the location of river gauging sites within the basin. The bottom left panel shows the distribution of annual average temperature. Finally, the bottom right panel shows the basin divided into commonly recognized sub-basins. The Upper Niger Basin includes all of the sub basins above the Inner Delta (red area) i.e. Siguiri, Koulikoro (or Sélingué) and Douna (or Bani) watersheds. The Niger Basin is experiencing considerable pressures on ecosystem resources and with good reason: all 9 countries in the active basin rank among the bottom 40 countries on the Human Development Index (UNDP, 2010). Over 100 million people inhabit the Niger basin distributed in nine countries, namely Benin, Burkina Faso, Cameroon, Chad, Cote D’Ivoire, Guinea, Mali, Niger, and Nigeria (Fig. 1). Average population growth rate is estimated at 2.7% and the rate of urbanization at 4.3%, both numbers among the highest rates in the world (UNFPA, 2010). Approximately 70% of the population depends on agriculture for their livelihood and overwhelmingly on rain-fed agriculture, and 60% lack access to a developed source of water. Somewhat paradoxically, the basins’ environmental and water resources are currently grossly underutilized. The irrigation potential is es #climate #variability ... https://www.youtube.com/watch?v=u4LrrX-yYvM

New Frontiers in Tectonic Research Online Course https://giladjames.com Section: Tunisian Transtensive Basins in Tethyan Geodynamic Context and Their Post-Tortonian Inversion Lesson: Oligocene New Frontiers in Tectonic Research. This course is brought to you by Gilad James Mystery School. Learn more at Gilad James.com. Introduction Generally, the geological and structural context of Tunisia can be described, from the North to the South, in terms of the structural domains illustrated on Fig. 1: The Alpine zone, composed of the Tellian Atlas, characterized by the stacking of allochthonous units (Jauzein et al., 1965; Biely et al., 1974; Rouvier, 1977; Ben Ferjani et al., 2006; Ould Bagga et al., 2006) and a series of imbricate thrust slices, whose front corresponds to the major Teboursouk overthrust (Zargouni, 1975; Perthuisot, 1978). The diapir zone (DZ), represented by the N050-trending Triassic outcrops of northern Tunisia (Perthuisot, 1978). The Atlasic zone includes the Northern Atlas, the central Atlas, the southernmost Atlas and the "North-South Axis". The central Atlas and the Northern Atlas are characterized by a bundle of N040-050 anticlinal folds that are cut orthogonally by a graben system. The southernmost Atlas is made up of E-W folds, inflected towards N060 at their terminations and bounded by the major faults of Gafsa and Négrine-Tozeur striking N120-130 (Zargouni, 1985). The "North-South Axis" comprises a folded and faulted zone delimiting the central Atlas (sensu lato) and the Eastern Atlas. It corresponds to a zone of major heterogeneity giving rise to N-S trending faults (Burollet, 1956; Turki, 1984, 1985, Gourmelen, 1984; Abbès, 2004). The Eastern platform is characterized by a weakly folded thick Neogene succession that extends eastward to the Malta scarp. The Saharan platform is characterized by folded Paleozoic rocks of the African craton, and makes up the foreland of the Atlasic chains (Fig. 1). The present architecture of the Saharan Atlas in Tunisia is defined by two principal models: The first one (Fig. 1) emphasizes a general SW-NE geological structure in successive and parallel bands represented by the tellian zone and the diapirs zone in the North, the central Atlas then the southernmost Atlas with oblique orientation and installed within a NW-SE corridor. These fields are bordered in the East by the “North-South Axis” (Castany, 1951; Burollet, 1956, 1991; Rouvier, 1977; Zargouni, 1985, 1986). Location of Tunisia in the eastern Maghreb: A: general context; B- schematic tectonic map of Tunisia. In B: a- major thrust, b- major faults, c- major anticlines, d- Trias, e- grben, f- limit of Kasserine Island The second model (Fig. 2) frames atlasic Tunisia in a big E-W strike-slip corridor which controls at first the facies distribution during the Meso-Cenozoïc sedimentation and generates later long echelon folds in the sedimentary cover by dextral shear zone (Ben Ayed 1980; Ben Ayed and Viguier, 1981; Ben Ayed, 1986; El Ghali et al., 2003). Simplfied tectonic map of Tunisian Atlasic domain (Ben Ayed and Viguier, 1981). 1: anticline; 2: syncline; 3: strike-slip fault; 4: rift; 5: flexure; 6: slipping thrust front; 7: thrust; 8: imbrications; 9: anticlinal alignment; 10: eastern extension of this alignment from the bathymetrical data; 11: pre-alpine; 12: Triassic outcrops #new #frontiers #in #tectonic #research ... https://www.youtube.com/watch?v=iR7GA8uAbJc

Multi-purposeful Application of Geospatial Data Online Course https://giladjames.com Section: Introduction to Navigation Systems Lesson: PMMs Multi-purposeful Application of Geospatial Data. This course is brought to you by Gilad James Mystery School. Learn more at Gilad James.com. Introduction Navigation refers to the method of determining aspects such as position, speed, and direction during travel. In the pre-modern era, direction and position were determined using an altazimuth, a compass, and a map; these are now considered primitive forms of navigation. As a result of modern developments in science and technology, exact positions and speeds are determined using equipment such as artificial satellites, global navigation satellite system (GNSS), inertial navigation systems (INS), etc. In the modern sense, navigation is mechanical devices equipped in ground vehicles, ships, and aircraft to determine their positions. Navigation is classified into two categories in this study: physical model-based methods (PMMs) and external data-based methods (EDMs). Examples of PMMs are inertial navigation systems (INS) and dead-reckoning navigation. They determine the existing position of an object by measuring various changes in its state, such as velocity and acceleration. The global navigation satellite system (GNSS) is an excellent representative of EDMs. Methods to determine longitude and latitude using polar stars or the sun considered as EDMs, which is utilized in the spacecraft nowadays. PMM and EDM have duality. The accuracy of PMMs is exponentially proportional to the cost, and the error increases over time. However, information can be obtained for three axes (X, Y, and Z); this is a stable configuration as no communication problems are incurred. EDMs are relatively cheap and the accuracy is pre-defined according to sensor. However, there may be some restrictions on communication. The navigation equipment in ground vehicles and the orbit propagator in spacecraft are designed to complement each other, considering the properties of tools such as the INS/GNSS. In the case of spacecraft, auxiliary navigation systems using data compression were proposed due to the unpredictable space environment and limited communication. The orbital equation used in spacecraft is represented by a nonlinear differential equation containing multiple perturbation terms, which makes the determination of orbit numerically complex. Generally, a precise determination of orbit is made on the ground, and the information is then transmitted to the spacecraft periodically. However, Deep space communication is restrictive and expensive. Therefore, the cost of communication can be reduced by compressing orbital data. For Low Earth Orbit satellites, the deviations between nominal and real orbit are compressed in the form of Fourier coefficients by using the periodic characteristics of the trajectory. Deep space explorer orbit compression and transmission were proposed using B-spline . #multi-purposeful #application #of #geospatial #data ... https://www.youtube.com/watch?v=V9fhJ9P76Rk