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2021 ◽  
Vol 8 (5) ◽  
pp. 84-97
Author(s):  
J. Marvin Herndon

Despite the importance for understanding the nature of the geomagnetic field, and especially its potential for radically disrupting modern civilization [1], virtually all scientific publications relating to it are based upon the false assumption that the geomagnetic field is generated in the Earth’s fluid core. By adhering to an outmoded paradigm, members of the geoscience community have potentially exposed humanity to globally devastating risks, leaving it unprepared for an inevitable geomagnetic field collapse. There is no scientific reason to believe that the geomagnetic field is generated within the fluid core. Convection is physically impossible in the fluid core due to its compression by the weight above and its inability to sustain an adverse temperature gradient. There is no evidence of ongoing inner core growth to provide energy to drive thermal convection or to cause compositional convection. Moreover, there is no mechanism to account for magnetic reversals and no means for magnetic seed-field production within the fluid core to initiate dynamo amplification. Earth’s nuclear georeactor, seat of the geomagnetic field, has none of the problems inherent in putative fluid-core geomagnetic field production. With a mass of about one ten-millionth that of the fluid core, georeactor sub-shell convection can potentially be disrupted by great planetary trauma, such as an asteroid impact, or by major solar outbursts or even by human activities, for example, by deliberate electromagnetic disturbance of the near-Earth environment, including the Van Allen belts. Furthermore, sub-shell convection disruption might trigger surface geophysical disasters, such as super-volcano eruptions [2-4]. Scientists have a fundamental responsibility to tell the truth and to provide scientific understanding that benefits humanity.


2021 ◽  
Vol 503 (4) ◽  
pp. 5611-5623
Author(s):  
Troy J Raen ◽  
Héctor Martínez-Rodríguez ◽  
Travis J Hurst ◽  
Andrew R Zentner ◽  
Carles Badenes ◽  
...  

ABSTRACT Most of the dark matter (DM) search over the last few decades has focused on weakly interacting massive particles (WIMPs), but the viable parameter space is quickly shrinking. Asymmetric dark matter (ADM) is a WIMP-like DM candidate with slightly smaller masses and no present-day annihilation, meaning that stars can capture and build up large quantities. The captured ADM can transport energy through a significant volume of the star. We investigate the effects of spin-dependent ADM energy transport on stellar structure and evolution in stars with 0.9 ≤ M⋆/M⊙ ≤ 5.0 in varying DM environments. We wrote a mesa module1 that calculates the capture of DM and the subsequent energy transport within the star. We fix the DM mass to 5 GeV and the cross-section to 10−37 cm2, and study varying environments by scaling the DM capture rate. For stars with radiative cores (0.9 ≤ M⋆/M⊙ ≲ 1.3 ), the presence of ADM flattens the temperature and burning profiles in the core and increases main-sequence (MS) (Xc > 10−3) lifetimes by up to $\sim \! 20{{\ \rm per\ cent}}$. We find that strict requirements on energy conservation are crucial to the simulation of ADM’s effects on these stars. In higher mass stars, ADM energy transport shuts off core convection, limiting available fuel and shortening MS lifetimes by up to $\sim \! 40{{\ \rm per\ cent}}$. This may translate to changes in the luminosity and effective temperature of the MS turnoff in population isochrones. The tip of the red giant branch may occur at lower luminosities. The effects are largest in DM environments with high densities and/or low velocity dispersions, making dwarf and early forming galaxies most likely to display the effects.


Author(s):  
Nicholas M. Leonardo ◽  
Brian A. Colle

AbstractThe largest medium-range (72-120 h) cross-track errors (CTE) of tropical cyclone (TC) forecasts from the Global Ensemble Forecast System (GEFS) over the northern Atlantic Ocean are examined for the 2008-2016 seasons. The 38 unique forecasts within the upper-quartile most negative CTEs (i.e., left-of-track bias larger than 250 km by 72 h) do not have a clear common source of steering error, though 12 of the forecasts involve the underprediction of a weak upper-level trough to the west of the TC by 36 h. Meanwhile, at least 18 of the 36 most positive CTEs (right-of-track bias) are associated with TCs embedded in the southwest extent of a subtropical ridge, the strength of which is increasingly underpredicted during the first 24 h of the forecast. Excessive height falls north of the TC are driven by overpredicted divergence aloft, which corresponds to overpredicted TC outer-core convection. The convection is triggered by a 5-to-20% overprediction of near-TC moisture and instability in the initial conditions. Weather Research Forecast (WRF) simulations are run at 36-, 12-, and 4-km grid spacing for select right-of-track cases, using the GEFS for initial and lateral boundary conditions. The 36-km WRF reproduces the same growth of errors as the GEFS due to in part sharing the same stability and moisture errors in the initial conditions. Changes in the convective parameterization affect how quickly these errors grow by affecting how much convection spins-up. The addition of a 4-km nest with no convective parameterization causes the errors to grow ~20% faster, resulting in an even larger right-of-track error.


2020 ◽  
Vol 148 (10) ◽  
pp. 4209-4229
Author(s):  
Tobias Kremer ◽  
Elmar Schömer ◽  
Christian Euler ◽  
Michael Riemer

AbstractMajor airstreams in tropical cyclones (TCs) are rarely described from a Lagrangian perspective. Such a perspective, however, is required to account for asymmetries and time dependence of the TC circulation. We present a procedure that identifies main airstreams in TCs based on trajectory clustering. The procedure takes into account the TC’s large degree of inherent symmetry and is suitable for a very large number of trajectories . A large number of trajectories may be needed to resolve both the TC’s inner-core convection as well as the larger-scale environment. We define similarity of trajectories based on their shape in a storm-relative reference frame, rather than on proximity in physical space, and use Fréchet distance, which emphasizes differences in trajectory shape, as a similarity metric. To make feasible the use of this elaborate metric, data compression is introduced that approximates the shape of trajectories in an optimal sense. To make clustering of large numbers of trajectories computationally feasible, we reduce dimensionality in distance space by so-called landmark multidimensional scaling. Finally, k-means clustering is performed in this low-dimensional space. We investigate the extratropical transition of Tropical Storm Karl (2016) to demonstrate the applicability of our clustering procedure. All identified clusters prove to be physically meaningful and describe distinct flavors of inflow, ascent, outflow, and quasi-horizontal motion in Karl’s vicinity. Importantly, the clusters exhibit gradual temporal evolution, which is most notable because the clustering procedure itself does not impose temporal consistency on the clusters. Finally, TC problems are discussed for which the application of the clustering procedures seems to be most fruitful.


2020 ◽  
Vol 7 (5) ◽  
pp. 283-303
Author(s):  
J. Marvin Herndon

A recent PLOSONE article utilized tabulations of opinions obtained from federal scientists to assert “perceived losses of scientific integrity under the Trump Administration.” The article presupposes the wide-spread existence of scientific integrity among federal scientists, which I refute based upon documented 40+ years’ experience making fundamental scientific discoveries which the scientific establishment systematically ignores and in instances has attempted to suppress. These discoveries include, but are not limited to: Earth’s nickel-silicide inner-core composition, the physical impossibility of both mantle convection and Earth-core convection; recognition that Earth’s early formation as a Jupiter-like gas giant makes it possible to derive virtually all geological and geodynamic behavior of our planet, including origin of continents and oceans, ocean floor topography, origin of mountains characterized by folding, primary initiation of fjords and submarine canyons, and two previously unanticipated potentially variable energy sources - nuclear fission and stored energy of protoplanetary compression; nuclear-fission-reactor origin of planetary magnetic fields, including the geomagnetic field; thermonuclear ignition of stars and the reason why the multitude of galaxies display just a few patterns of luminous stars; and, particulate pollution, not greenhouse gases, as the main cause of local and global warming. A scientific community, apparently suffering from Integrity Deficit Syndrome, cannot be expected to provide a truthful assessment, especially when queried about the actions of a president who might change the science landscape under which they flourish.


2019 ◽  
Vol 76 (8) ◽  
pp. 2309-2334 ◽  
Author(s):  
Buo-Fu Chen ◽  
Christopher A. Davis ◽  
Ying-Hwa Kuo

Abstract Given comparable background vertical wind shear (VWS) magnitudes, the initially imposed shear-relative low-level mean flow (LMF) is hypothesized to modify the structure and convective features of a tropical cyclone (TC). This study uses idealized Weather Research and Forecasting Model simulations to examine TC structure and convection affected by various LMFs directed toward eight shear-relative orientations. The simulated TC affected by an initially imposed LMF directed toward downshear left yields an anomalously high intensification rate, while an upshear-right LMF yields a relatively high expansion rate. These two shear-relative LMF orientations affect the asymmetry of both surface fluxes and frictional inflow in the boundary layer and thus modify the TC convection. During the early development stage, the initially imposed downshear-left LMF promotes inner-core convection because of high boundary layer moisture fluxes into the inner core and is thus favorable for TC intensification because of large radial fluxes of azimuthal mean vorticity near the radius of maximum wind in the boundary layer. However, TCs affected by various LMFs may modify the near-TC VWS differently, making the intensity evolution afterward more complicated. The TC with a fast-established eyewall in response to the downshear-left LMF further reduces the near-TC VWS, maintaining a relatively high intensification rate. For the upshear-right LMF that leads to active and sustained rainbands in the downshear quadrants, TC size expansion is promoted by a positive radial flux of eddy vorticity near the radius of 34-kt wind (1 kt ≈ 0.51 m s−1) because the vorticity associated with the rainbands is in phase with the storm-motion-relative inflow.


2019 ◽  
Vol 147 (7) ◽  
pp. 2657-2676 ◽  
Author(s):  
Christian Euler ◽  
Michael Riemer ◽  
Tobias Kremer ◽  
Elmar Schömer

Abstract Extratropical transition (ET) of tropical cyclones involves distinct changes of the cyclone’s structure that are not yet well understood. This study presents for the first time a comprehensive Lagrangian description of structure change near the inner core. A large sample of trajectories is computed from a convection-permitting numerical simulation of the ET of Tropical Storm Karl (2016). Three main airstreams are considered: those associated with the inner-core convection, inner-core descent, and the developing warm conveyor belt. Analysis of these airstreams is performed both in thermodynamic and physical space. Prior to ET, Karl is embedded in weak vertical wind shear and its intensity is impeded by excessive detrainment from the inner-core convection. At the start of ET, vertical shear increases and Karl intensifies, which is attributable to reduced detrainment and thus to the formation of a well-defined outflow layer. During ET, the thermodynamic changes of the environment impact Karl’s inner-core convection predominantly by a decrease of θe values in the inflow layer. Notably, notwithstanding Karl’s weak intensity, its inner core acts as a “containment vessel” that transports high-θe air into the increasingly hostile environment. Inner-core descent has two origins: (i) mostly from upshear-left above 4-km height in the environment and (ii) boundary layer air that ascends in the inner core first and then descends, performing rollercoaster-like trajectories. At the end of the tropical phase of ET, the developing warm conveyor belt comprises air masses from several different source regions, and only partly from the cyclone’s developing warm sector, as expected for extratropical cyclones.


2019 ◽  
Vol 147 (2) ◽  
pp. 591-605 ◽  
Author(s):  
Sarah D. Ditchek ◽  
John Molinari ◽  
Kristen L. Corbosiero ◽  
Robert G. Fovell

Abstract Storm-centered IR brightness temperature imagery was used to create 6-h IR brightness temperature difference fields for all Atlantic basin tropical cyclones from 1982 to 2017. Pulses of colder cloud tops were defined objectively by determining critical thresholds for the magnitude of the IR differences, areal coverage of cold-cloud tops, and longevity. Long-lived cooling pulses (≥9 h) were present on 45% of days overall, occurring on 80% of major hurricane days, 64% of minor hurricane days, 46% of tropical storm days, and 24% of tropical depression days. These cooling pulses propagated outward between 8 and 14 m s−1. Short-lived cooling pulses (3–6 h) were found 26.4% of the time. Some days without cooling pulses had events of the opposite sign, which were labeled warming pulses. Long-lived warming pulses occurred 8.5% of the time and propagated outward at the same speed as their cooling pulse counterparts. Only 12.2% of days had no pulses that met the criteria, indicating that pulsing is nearly ubiquitous in tropical cyclones. The environment prior to outward propagation of cooling pulses differed from warming pulse and no pulse days by having more favorable conditions between 0000 and 0300 LT for enhanced inner-core convection: higher SST and ocean heat content, more moisture throughout the troposphere, and stronger low-level vorticity and upper-level divergence.


2018 ◽  
Vol 45 (1) ◽  
pp. 98-107 ◽  
Author(s):  
Alexander J. Evans ◽  
Sonia M. Tikoo ◽  
Jeffrey C. Andrews-Hanna
Keyword(s):  

2017 ◽  
Vol 56 (10) ◽  
pp. 2801-2819 ◽  
Author(s):  
Ryo Oyama

AbstractThe temporally dense geostationary satellite observations made possible by recent technological advances enable atmospheric motion vectors (AMVs) to be derived that are suitable for capturing atmospheric flows even of mesoscale phenomena, for which in situ data are scarce. Tropical cyclone (TC) outflows around the cloud top, reflecting TC secondary circulation, were computed by using AMVs derived from successive Multifunctional Transport Satellite (MTSAT) imagery, and the relationship between TC intensification rate (defined as the change of the best-track maximum sustained wind in the previous 24 h) and the outflow was investigated for 44 TCs occurring during 2011–14. During the TC intensification phase, temporal changes in the outflow were generally synchronous with changes in the cloud-top temperature of TC inner-core convective clouds detected by MTSAT infrared band. It was noteworthy that the intensification rates of 66% of the TCs peaked 0–36 h after outflow maximization and that the intensification rate for TCs with a maximum rate of >15 m s−1 day−1 peaked after the outflow maximum. Furthermore, TCs with a large intensification rate and latent-heat release around the midlevel tended to have a large outflow during the intensification phase. A comparison of TCs with and without convective bursts (CBs) revealed that the correlation between outflow and the TC intensification rate was higher for TCs accompanied by CBs than for those without CBs, implying that a rapid deepening of inner-core convection is important for intensification of a TC’s secondary circulation. The outflow tended to be most correlated with the TC intensification rate 0–6 h earlier.


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