Solar Terrestrial Physics

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A brief history of solar-terrestrial physics in Australia

A brief history of solar-terrestrial physics in Australia

Over more than one century beginning in the late 1800’s, Australia has exhibited a rich history of achievement in solar-terrestrial physics, ranging from simple geomag- netic measurements to sophisticated radars and satel- lite payloads. These endeavours have been supported by competent and continuing theoretical and modelling programs. Beginning at the time of the Second World War applied research was fostered by close collaboration between UK, Australian and New Zealand physicists which later included the USA. As a consequence, great progress was made in association with the World War II effort and this continued through until the 1960’s, and was a time when Australia was at the forefront of inter- national STP research. An advantage over this period was, due the history evolving over the previous three decades that political implications were largely and con- veniently absent from scientific planning and implemen- tation. However, in the following three decades, until the end of the century, there was significant investment from the Australian Federal Government to expand research with applied research increasing, albeit sup- ported with only modest private industry investment. In the new millennium, more emphasis has been placed on large projects. For example, the future multibillion dol- lar astronomical telescope, the Square Kilometre Array Project (SKA 2015) under development coupled with the
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Paradigm transitions in solar–terrestrial physics from 1900: my personal view

Paradigm transitions in solar–terrestrial physics from 1900: my personal view

Abstract. Solarterrestrial physics, like any other scientific field, has evolved and developed by replacing older theories with newer theories. Unfortunately, each generation of young researchers tends to learn naturally only the latest, and perhaps the most popular theory and believes that it is the only useful one to pursue. Therefore, they do not necessarily realize that in the past the theory they chose had struggled to reach its presently accept- able state, and that eventually it might be replaced with a new theory. Two generations of scientists or in some subjects even more generations tend to be guided by one particular idea or theory. Thus, among us (namely, one or two generations) a high degree of agreement occurs, both on the theoretical assumptions and on the problem to be solved within the framework provided by the theory. Such an idea or theory was termed paradigm by Kuhn (1970). The purpose of this article is to describe several examples of the transition of paradigms and ideas in the subjects of solarterrestrial physics. The examples are subjects that experienced a paradigm change after prevail- ing in the field for a few generations and also some that are perhaps on the verge of the transition. The chosen subjects are (1) Stormer’s single particle theory to Chapman’s plasma theory (1907–1963), (2) the auroral zone to the auroral oval (1860–1971), (3) the closed to open magnetosphere (1931–1971), (4) the current system contro- versies (1918–1963) and (1964–present), (5) the fixed pattern concept to the concept of auroral/magnetospheric substorms (1935–1982), (6) the importance of the interplanetary magnetic field (IMF) in the development of geomagnetic storms (1905–1966), (7) the ring current: solar wind protons to oxygen ions from the ionosphere (1933–1977), (8) the storm–substorm controversy (1963–present), (9) substorm onset (1964-present), (10) solar flares (1958–present) and (11) sunspots (1961–present).
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The capacity building and science enabling activities of the IUGONET for the solar terrestrial research community

The capacity building and science enabling activities of the IUGONET for the solar terrestrial research community

Geophysical Year (IGY, 1957 to 1958) to avoid catastro- phic damage to all the observed geophysical data. This system has evolved over the approximately 60 years of its operation for the STP community, especially in Japan. The Space Physics Interactive Data Resource (NOAA National Geophysical Data Center 2014) of the former WDC for Solar-Terrestrial Physics, Boulder, in the National Geophysical Data Center (NGDC)/National Ocean and Atmosphere Administration (NOAA), is the pioneer database for archiving STP observational data. Satellite mission data from the upper atmosphere and heliosphere have been archived at the National Space Science Data Center (NSSDC) of the National Aero- nautics and Space Administration (NASA) (Grayzeck 2014) since 1966. These include the Virtual Magneto- spheric Observatory (VMO), Virtual Heliospheric Ob- servatory (VHO), and Virtual Solar Observatory (VSO), which constitute satellite data archives for each field and are NASA projects that are grouped under the ab- breviated name ‘VxO.’
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Simulating solar induced chlorophyll fluorescence in a boreal forest stand reconstructed from terrestrial laser scanning measurements

Simulating solar induced chlorophyll fluorescence in a boreal forest stand reconstructed from terrestrial laser scanning measurements

soybean and cotton. Another radiative transfer model, FluorFLIGHT (Hernández-Clemente et al., 2017) couples the 3D ray-tracing forest radiative transfer model FLIGHT and the leaf fluorescence model FLUSPECT. FLIGHT describes the tree canopy as consisting of homo- geneous tree crowns and gaps between them (North, 1996). The results of FluorFLIGHT showed that the TOC SIF signal is greatly influenced by canopy structure for complex canopy types with heterogeneity in both horizontal and vertical dimensions. Although these two models re- present a significant step forward in complexity, they approximate plant crowns as geometrical object filled homogeneously with leaves without considering leaf clumping effects. Contrary to this, the 3D Discrete Anisotropic Radiative Transfer (DART) model can be used to provide a more realistic representation of plant architecture by ex- plicitly describing the foliage distribution, including leaf clumping at branch and crown levels, along with detailed geometry of stems and branches (Gastellu-Etchegorry et al., 2017). DART also simulates spectrally resolved radiative budget of vegetation scenes, which can be used to directly estimate the light regime and instantaneous incoming photosynthetically active radiation (PAR) of each leaf. Subsequently, it is possible to separate foliage into sun and shade adapted parts and assign them specific optical properties and fluorescence yields as a function of light regime or incoming PAR (Gastellu-Etchegorry et al., 2018). The parameterization of leaf geometry, distribution and clumping at branch and crown levels can, however, be very laborious and consequently forced to be simplified, especially for a large canopy. In this study we present a methodological scheme to assimilate high resolution forest canopy 3D structural data, acquired with a terrestrial laser scanner in a Silver birch stand, into the DART model. The scheme is combined with empirical data and used to simulate TOC SIF in the heterogeneous forest stand with consideration to multiscale leaf clumping and understory vegetation. The potential of the modelling scheme is next demonstrated by conducting a local sensitivity analysis of TOC SIF to key structural, biochemical and physiological factors.
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Terrestrial Mammals

Terrestrial Mammals

Widespread distribution, presence in broad range of habitats and the European status of least concern justify current Irish assessment... Ireland, but proposed for addition to Schedule 6[r]

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Terrestrial Mammals

Terrestrial Mammals

Category – All terrestrial mammals referenced in the text are listed and assigned to the following categories: Native/naturalised – all species native to Ireland or naturalised in Ireland before 1500 i.e. the species which were assessed; Post-1500 – the species introduced to Ireland by man after 1500; Vagrant – only single records confirmed; Feral – species originating from escaped domestic stock. See Pg 5 Taxonomic and geographic scope for full details. IRL 2019 Status - Red list status for Ireland based on this assessment; RE - Regionally Extinct, VU – Vulnerable, NT - Near threatened, DD - Data deficient, LC – Least Concern; NA – Not Assessed. EU Status - Red list status for Europe, based on Temple & Terry (2007); Global Status - Red List status, taken from IUCN (2019); UK Status – Conservation status in the UK; PS – Priority Species, SoCC – Species of
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The Terrestrial Metasystem

The Terrestrial Metasystem

magnetosphere, atmosphere, geosphere, hydrosphere and biosphere systems generate a global.. 71.[r]

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On the Apparent Relationship Between Total Solar Irradiance and the Atmospheric Temperature at 1 Bar on Three Terrestrial-type Bodies

On the Apparent Relationship Between Total Solar Irradiance and the Atmospheric Temperature at 1 Bar on Three Terrestrial-type Bodies

The temperature of the atmospheres at 1 bar (101.3kPa) of all three of the terrestrial-type planetary bodies with thick atmospheres, despite the large differences between them both in atmospheric greenhouse gas content and albedo (Figure 1), appears to relate almost exclusively to the quaternary root of relative differences in TSI (Figure 2). This seems to point to the main determinants of planetary atmospheric temperatures of terrestrial-type bodies which possess thick atmospheres, being atmospheric pressure and TSI, not albedo and greenhouse gas content. If this relationship proves to be a real feature of planetary atmospheric physics, it will have far- reaching effects for how albedo and ‘greenhouse’ gas content are treated when calculating atmospheric temperatures in the future. The relationship tends to add to previous work that indicates the likelihood of a very low or a zero, climate sensitivity for CO 2 [2-4,14,17,18,24-29].
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Terrestrial ground temperature variations in relation to solar magnetic variability, including the present Schwabe cycle

Terrestrial ground temperature variations in relation to solar magnetic variability, including the present Schwabe cycle

The next question is that of the character of the new Grand Episode. It is unlikely that a Grand Minimum, such as the Maunder one, may be expected, because Grand Minima occur only during negative phases of the 2300 years lasting solar Hallstatt oscillation (Steinhilber et al., [27]; De Jager and Duhau, [24]). A diagram like Figure 10 in Versteegh [30] shows that phases of pro- nounced low solar (Grand Minima) activity tend to clus- ter together during periods of negative Hallstatt oscilla- tions. Actually, the Hallstatt periodicity is just a reflex of the repetitive clustering of Grand Minima each 2300 years. The Hallstatt oscillation changed from negative to positive in the middle of the 20 th century. Therefore we
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Cyclotron radiation from electron streams gyrating in the Jovian magnetosphere, the terrestrial exosphere and the solar active corona

Cyclotron radiation from electron streams gyrating in the Jovian magnetosphere, the terrestrial exosphere and the solar active corona

For cycltron radiation from a charged particle gyrating about a static magnetic field line, the wave vector 2 gyrates with the gyrating radiator and g forms a cone for one complete gyrat[r]

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Correlative Study Between Harmonics of Daily Variation of
Cosmic Rays and Solar Terrestrial Parameters

Correlative Study Between Harmonics of Daily Variation of Cosmic Rays and Solar Terrestrial Parameters

It is well established from the diffusion-convection theory that cosmic rays intensity varies with variation in solar wind velocity and a number of studies have been done to derive relation between them (Shrivastava et al., 1994; Ahluwalia, 1991, Rangrajan et al. 2000).

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A Bayesian approach to comparing theoretic models to observational data: A case study from solar flare physics

A Bayesian approach to comparing theoretic models to observational data: A case study from solar flare physics

The temporal evolution of temperature and emission measure in a C3.0 solar flare observed on March 26, 2002 has been analysed. During a typical solar flare, the temperature rises from less than one MK up to ∼ 20 MK, and then cools down to the pre-flare temperatures. In the example under consideration here, Raftery et al. (2009) used different instruments to track this evolution: the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI; > 5 MK), GOES-12 (5 − 30 MK), the Transition Region and Coronal Explorer (TRACE 171 ˚ A ; 1 MK), and the Coronal Diagnostic Spectrometer (CDS; ∼ 0.03 − 8 MK). We note here that TRACE data were not included in the emission measure analysis. This is as a result of the instrument being sensitive to multiple emission lines, making it complex to define the contribution function. The reader is referred to Raftery et al. (2009) which outlines the reasons why and at which particular time of the flare each particular instrument was employed.
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Multi-objective optimisation of integrated space-based and terrestrial solar energy systems

Multi-objective optimisation of integrated space-based and terrestrial solar energy systems

With η c the solar to electric power conversion efficiency and η S the power system effiency. S 0 is the specific power at 1AU, r S is the distance from the Sun (in AU) and α is the elevation angle of the Sun over the solar panels. For the purpose of this assessment the case of the sail tower concept is used, which rotates the solar panels to have continuous 90° irradiation. In the sail-tower concept A SPS is the area of the solar arrays. In the solar concentrator concept A SPS is the area of the solar concentrator. The power is then collected and beamed to the ground through a microwave transmitter operating at 2.54 GHz. The ground station antenna is designed to collect all the power transmitted, therefore its size depends on the distance from SPS to ground station, on the divergence of the beam and the incident angle of the microwave beam. It is assumed that the divergence is 3.85 × 10 − 4 radians, therefore the diameter
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QUANTUM PHYSICS AND FUNDAMENTAL PHYSICS IN SPACE

QUANTUM PHYSICS AND FUNDAMENTAL PHYSICS IN SPACE

• Instrument Engineer, Space Research Institute Graz, Austrian Academy of Sciences. • Lecturer in Audio Engineering, TU Graz[r]

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A Bridge Connecting Classical Physics and Modern Physics

A Bridge Connecting Classical Physics and Modern Physics

x + y + z − ct = x ′ + y ′ + z ′ − ct ′ = (1) We believe that time and spaces are dependent and should be shown in a frame which is applied not only to modern physics but also to classical physics. A 3-d s-t frame serves that purpose. We can draw the time dilation and length contraction between two inertial 3-d s-t frames. We can show that a 4-d s-t frame is the approxima- tion of a 3-d s-t frame, when the velocity of a moving frame is much less than the velocity of the medium. We also show that a 3-d s-t frame is equivalent to a 4-d s-t frame after properly converting coordinates between two frames.
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Community Development of Terrestrial and Semi-Terrestrial Invertebrates Along Environmental Gradients in a Reclaimed Watershed

Community Development of Terrestrial and Semi-Terrestrial Invertebrates Along Environmental Gradients in a Reclaimed Watershed

The development and expansion of surface mining for oil sands in the Wood Buffalo boreal region of northeastern Alberta has been a topic of economic and environmental importance for the past 50 years. Because of the further need for oil sands mining, companies continue to increase the expanse of their projects, which has resulted in significant peatland loss in the region (Rooney et al., 2012). Habitat disturbance caused by the mining process necessitates reclamation in the disturbed areas. There has been past success in reclamation of terrestrial upland habitats, as seen in Gateway Hill and South Bison Hills (both Syncrude Canada Ltd.) (MacDonald et al., 2012). However, given the extent of peatlands in this region’s landscape, there has been a shift in focus from upland reclamation practices to wetland and fen reclamation practices (Price et al., 2012). As a condition of continuing the operation of their mines, Syncrude Canada Ltd. was tasked in the construction and study of the Sandhill Fen Watershed, which is the first watershed built in the region and the first construction of a reclaimed wetland on soft tailings (Wytrykush et al., 2012). Design of the watershed began in 2007 (Syncrude, 2008), with construction occurring in 2010 (BGC Engineering, 2010) and culminating in 2012.
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Filling-in of near-infrared solar lines by terrestrial fluorescence and other geophysical effects: simulations and space-based observations from SCIAMACHY and GOSAT

Filling-in of near-infrared solar lines by terrestrial fluorescence and other geophysical effects: simulations and space-based observations from SCIAMACHY and GOSAT

We note filling-in (retrieved as F ) at 866 nm over parts of the Sahara desert (most apparent in May–September) and the Saudi Arabian peninsula where vegetation is sparse and a sig- nificant signal from chlorophyll fluorescence is not expected. We also note some negative filling-in values over these re- gions that have high radiances values. The memory effect of SCIAMACHY may contribute to these features as radiances at 866 nm show sometimes large gradients over these areas and our filtering scheme may not have completed removed all affected pixels. The SCIAMACHY memory effect may also affect the reference spectra, particularly for high values of radiance that correspond to the bright cloudy data over ocean. In addition, residual filling-in over the brightest areas may not have been well characterized by the cloudy ocean spectra. Cloudy spectra with high radiance values occur pri- marily in deep and frontal convection where cloud pressures are low. This may lead to an underestimation of filling-in from RRS when these spectra are used as a reference and thus over-estimation of the residual filling-in from terrestrial sources.
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The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 2: Accurate calibration of high spectral-resolution infrared measurements of surface solar radiation

The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 2: Accurate calibration of high spectral-resolution infrared measurements of surface solar radiation

Abstract. Quantitative knowledge of water vapor absorp- tion is crucial for accurate climate simulations. An open sci- ence question in this context concerns the strength of the water vapor continuum in the near infrared (NIR) at atmo- spheric temperatures, which is still to be quantified by mea- surements. This issue can be addressed with radiative clo- sure experiments using solar absorption spectra. However, the spectra used for water vapor continuum quantification have to be radiometrically calibrated. We present for the first time a method that yields sufficient calibration accuracy for NIR water vapor continuum quantification in an atmo- spheric closure experiment. Our method combines the Lan- gley method with spectral radiance measurements of a high- temperature blackbody calibration source ( < 2000 K). The calibration scheme is demonstrated in the spectral range 2500 to 7800 cm −1 , but minor modifications to the method enable calibration also throughout the remainder of the NIR spectral range. The resulting uncertainty (2σ ) excluding the contribu- tion due to inaccuracies in the extra-atmospheric solar spec- trum (ESS) is below 1 % in window regions and up to 1.7 % within absorption bands. The overall radiometric accuracy of the calibration depends on the ESS uncertainty, on which at present no firm consensus has been reached in the NIR. How- ever, as is shown in the companion publication Reichert and Sussmann (2016), ESS uncertainty is only of minor impor- tance for the specific aim of this study, i.e., the quantification of the water vapor continuum in a closure experiment. The calibration uncertainty estimate is substantiated by the inves- tigation of calibration self-consistency, which yields com- patible results within the estimated errors for 91.1 % of the
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Assimilating solar-induced chlorophyll fluorescence into the terrestrial biosphere model BETHY-SCOPE v1.0: model description and information content

Assimilating solar-induced chlorophyll fluorescence into the terrestrial biosphere model BETHY-SCOPE v1.0: model description and information content

We assessed the ability of satellite SIF observations to con- strain uncertainty in model parameters and uncertainty in spatiotemporal patterns of simulated GPP using a process- based terrestrial biosphere model. The results show that there is a strong constraint of parametric uncertainties across a wide range of processes including leaf growth dynamics and leaf physiology when assimilating just 1 year of SIF observa- tions. Combined, the SIF constraint on parametric uncertain- ties propagates through to a strong reduction in uncertainty in GPP. The prior uncertainty in global annual GPP is re- duced by 73 % from 19.0 to 5.2 Pg C yr −1 . Although model dependent, this result demonstrates the potential of SIF ob- servations to improve our understanding of GPP. We also showed that a data assimilation framework with error prop- agation such as this allows us to account for uncertainty in model forcing such as SWRad. Surprisingly, by including it into this framework with SIF observations, there is a net-zero effect on uncertainty in GPP due to the sensitivity of both SIF and GPP to radiation. This study is a crucial first step toward assimilating satellite SIF data to estimate spatiotemporal pat- terns of GPP. With the addition of other observational con- straints such as atmospheric CO 2 concentration or soil mois-
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TERRESTRIAL VEGETATION ASSESSMENT

TERRESTRIAL VEGETATION ASSESSMENT

Sensitivity mapping will be conservation planning information obtained from the South African National Biodiversity Institute (SANBI) datasets, which represents priori[r]

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