| Estimating Neutral Atmosphere Drivers using a Physical Model |
30-Mar-2009 |
9 pages |
| Authors:
Tim Fuller-Rowell; Cliff Minter; Mihail Codrescu; Mariangel Fedrizzi; COLORADO UNIV AT BOULDER
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 | In the initial phase of this study, research focused on implementing a physical model into an ensemble Kalman filter to estimate the location and magnitude of the upper atmospheric heating. Since the neutral atmosphere is strongly externally driven during geomagnetic storms, specifying the upper atmospheric heating is necessary when describing the time-dependent evolution of the neutral density. Challenges arise when only a portion of the upper atmosphere is observable. Because ... |
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| Radiation and Dissipation of Internal Waves Generated by Geostrophic Motions Impinging on Small-Scale Topography |
Feb-2009 |
171 pages |
| Authors:
Maxim Nikurashin; WOODS HOLE OCEANOGRAPHIC INSTITUTION MA DEPT OF PHYSICAL OCEANOGRAPHY
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| Observations and inverse models suggest that small-scale turbulent mixing is enhanced in the Southern Ocean in regions above rough topography. The enhancement extends 1 km above the topography suggesting that mixing is supported by breaking of gravity waves radiated from the ocean bottom. In other regions, gravity wave radiation by bottom topography has been primarily associated with the barotropic tide. In this study, we explore the alternative hypothesis that the ... |
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| Demonstration of Helicopter Multi-sensor Towed Array Detection System (MTADS) Magnetometry at Former Camp Beale, California |
01-Oct-2008 |
94 pages |
| Authors:
Jack Foley; David Wright; SKY RESEARCH ASHLAND OR
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| Helicopter Multisensor Towed Array Detection System (MTADS) Magnetometry (HeliMag) technology was demonstrated as part of the ESTCP Wide Area Assessment Pilot Program. This report documents the acquisition, processing, analysis, and interpretation of Helicopter Multisensor Towed Array Detection System Magnetometry data for unexploded ordnance related sites at nearly 5,000 acres at former Camp Beale, California. The performance criteria for positioning accuracy, system noise, data density, MEC parameter estimates, and operating parameters ... |
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| Interhourly Variability Index of Geomagnetic Activity and Its Use in Deriving the Long-Term Variation of Solar Wind Speed |
31 OCT 2007 |
33 pages |
| Authors:
Leif Svalgaard; Edward W. Cliver; AIR FORCE RESEARCH LAB HANSCOM AFB MA
|
| [1] We describe the detailed derivation of the interhourly variability (IHV) index of geomagnetic activity. The IHV index for a given geomagnetic element is mechanically derived from hourly values or means as the sum of the unsigned differences between adjacent hours over a 7-hour interval centered on local midnight The index is derived separately for stations in both hemispheres within six longitude sectors spanning the Earth using only local night ... |
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| An Alternative Method of Computing Altitude Adjustment Corrected Geomagnetic Coordinates as Applied to IGRF Epoch 2005 |
20-Jul-2007 |
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| Authors:
William Heres; Nelson A Bonito; ATMOSPHERIC AND ENVIRONMENTAL RESEARCH INC LEXINGTON MA
|
 | An updated set of altitude adjusted corrected geomagnetic coordinates has been calculated. The coordinates are based on the 10th generation IGRF model coefficients for Epoch 2005. The corrected geomagnetic coordinates at ground level are available as a lookup table, and a corresponding set of spherical harmonic coefficients for use in computing altitude adjusted corrected geomagnetic coordinates at various altitudes (after Baker and Wing [1998]) are also available. Both products are ... |
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| Thermospheric Space Weather Modeling |
JUN 2007 |
13 pages |
| Authors:
Frank A. Marcos; William J. Burke; Shu T. Lai; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
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| We review impacts of satellite drag and describe past, current and future capabilities designed to meet evolving operational requirements. Historically, thermospheric research has been data starved. Thus, from the early space age to the end of the 20th century little progress was made in satellite-drag modeling. This condition improved greatly with the development of empirical assimilative models and recent availability of comprehensive drag measurements. With the new Jacchia-Bowman 2006 model ... |
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| A Space-Based Proxy for the Dst Index |
18 MAY 2007 |
8 pages |
| Authors:
F. J. Rich; J. M. Bono; W. J. Burke; L. C. Gentile; AIR FORCE RESEARCH LAB HANSCOM AFB MA
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| The Dst index was created to monitor and quantify disturbances in the inner magnetosphere using ground-based, magnetic field measurements. The phases and strengths of geomagnetic storms are usually defined by the evolution of Dst. The standard Dst database is computed and maintained at the World Data Center for Geomagnetism, Kyoto. We demonstrate that the Dst index can also be approximated using magnetometers on spacecraft in near-Earth orbit. Measurements used in ... |
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| 3rd IAGA/ICMA Workshop on Vertical Coupling in the Atmosphere/Ionosphere System/ Abstract |
10 JAN 2007 |
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| Authors:
Dora Pancheva; BATH UNIV (UNITED KINGDOM)
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| The Final Proceedings for 3rd IAGA/ICMA Workshop on Vertical Coupling in the Atmosphere/Ionosphere 18 September 2006 - 22 September 2006. The 3rd IAGA/ICMA Workshop will focus primarily on those forcing mechanisms that originate in the lower atmosphere on their transmission into the atmosphere-ionosphere system and the ways in which these are influenced by changing solar geomagnetic and anthropogenic drivers. The workshop will address recent studies on atmospheric coupling with special ... |
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| International Heliophysical Year SCINDA Workshop/Abstract |
01 OCT 2006 |
35 pages |
| Authors:
Abebe Kebede; Jyoti Nair; NORTH CAROLINA AGRICULTURAL AND TECHNICAL SATE UNIV GREENSBORO DEPT OF PHYSICS
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| The first Heliophysical Year International SCINDA Workshop was held at Sal, Cape Verde, during the period of July 10-14, 2006. This 5-day workshop was organized by Air Force Research Laboratory, NC A&T State University, the and Instituto Nacional De Metereologica E Geofisica Republico De Cabo Verde (INMG). Representatives from Nigeria, Ethiopia, Cape-Verde, Cote D Ivoire, Malaysia and Congo Brazzaville participated in the workshop. The overall goals of the workshop were ... |
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| Reply to the Comment by M. Lockwood et al. on the IDV Index: Its Derivation and Use in Inferring Long-Term Variations |
21 SEP 2006 |
9 pages |
| Authors:
L. Svalgaard; E. W. Cliver; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| From an analysis of geomagnetic and solar wind data, Lockwood et al (1999) (hereinafter referred to as LSW99) reported that The solar coronal magnetic field had increased by more than a factor of two during the last century. If true, this would be an important discovery. Recently, Svalgaard and Cliver (2006) (hereinafter referred to as SCOS) reported an analysis based on our newly developed interdiurnal variability (IDV) index of geomagnetic ... |
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| The IDV Index: Its Derivation and Use in Inferring Long-Term Variations of the Interplanetary Magnetic Field Strength |
13 DEC 2005 |
10 pages |
| Authors:
Leif Svalgaard; Edward W. Cliver; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| On the basis of a consideration of Bartels' historical u index of geomagnetic activity, we devise an equivalent index that we refer to as the interdiurnal variability (IDV). The IDV index has the interesting and useful property of being highly correlated with the strength of the interplanetary magnetic field (B; R2 = 0.75) and essentially unaffected by the solar wind speed (V; R = 0.01) as measured by spacecraft. This ... |
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| Multidimensional Quasi-Linear Diffusion of Radiation Belt Electrons |
28 JUL 2005 |
5 pages |
| Authors:
J. M. Albert; S. L. Young; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE WEATHER CENTER OF EXCELLENCE
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| We consider diffusion of outer zone radiation belt electrons by chorus waves. Quasi-linear diffusion coefficients valid outside the plasmasphere have only been calculated recently, and indicate that the energy and cross diffusion rates can be comparable to that for pitch angle diffusion. Proper solution of the diffusion equation for phase space density must therefore be based on the full diffusion tensor, but this has been plagued by numerical problems associated ... |
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| Near-Simultaneous Plasma Structuring in the Midlatitude and Equatorial Ionosphere During Magnetic Superstorms |
29 APR 2005 |
5 pages |
| Authors:
Santimay Basu; Sunanda Basu; Keith M. Groves; Eileen MacKenzie; M. J. Keskinen; F. J. Rich; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| Near simultaneous formation of ionospheric plasma density structures at middle and equatorial latitudes during the intense magnetic storms of October 29-31, 2003; July 15, 2000; and March 30-31, 2001 is investigated. The evolution of these structures is explored by measuring amplitude scintillation of satellite signals at 250 MHz, determining zonal irregularity drifts and by detecting equatorial plasma bubbles with DMSP satellites. During abrupt decreases of SYM-H (1-minute resolution Dst) that ... |
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| Understanding Midlatitude Space Weather: Storm Impacts Observed at Bear Lake Observatory on 31 March 2001 |
26 OCT 2004 |
17 pages |
| Authors:
J. J. Sojka; D. Rice; J. V. Eccles; F. T. Berkey; P. Kintner; W. Denig; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
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| On 30 March 2001 in the late evening an auroral display was observed over the United States of America. The Bear Lake Observatory (BLO) magnetometer in Utah measured changes of 550 nT in less than 30 min. During the same period, BLO ionosonde measurements showed deep high-frequency radio wave absorption up to 7 MHz. BLO's CPS single-frequency receiver experienced geolocation errors of 20 m for over 3 hours. These storm ... |
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| The Use of Geophysical Data in Studies of the Historical Solar-Terrestrial Environment |
29 SEP 2004 |
12 pages |
| Authors:
M. A. Shea; D. F. Smart; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| Recent studies of the solar-terrestrial environment for the past 500 years have necessitated the use of a variety of historical databases: nitrates in ice cores, knowledge of large volcanic eruptions, sunspot numbers, mid-latitude aurora, and geomagnetic records. The nitrate data are being used to identify large solar proton fluence events. The volcanic records help to provide time markers for the ice core. The records of major geomagnetic storms and mid-latitude ... |
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| The Energetic Electron Response to Magnetic Storms: HEO Satellite Observations |
10 JUL 2004 |
20 pages |
| Authors:
J. F. Fennell; J. B. Blake; R. Friedel; S. Kanekal; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
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| The energetic electron observations from the HEO 97-068 satellite are used to study the electron response to magnetic storms in the inner magnetosphere during 1998-2002. The observations cover L values in the range 2.5 less than or equal L less than or equal 6. The same L values are covered at both high (>2.3 Re) and low (1.5 MeV electron fluxes were ^10-16% of the high-altitude fluxes for L = ... |
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| Transient Sheets of Field-Aligned Current Observed by DMSP During the Main Phase of a Magnetic Superstorm |
16 JUN 2004 |
18 pages |
| Authors:
Cheryl Y. Huang; William J. Burke; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| Reported are the first observations of intense (^1 A/m) but transient sheets of field-aligned currents (FACS) that couple of the central plasma sheet with the auroral ionosphere near the maximum epochs of magnetic superstorms. Maximum magnetic perturbations associated with the FACs normally develop at middle (55 deg - 60 deg) magnetic latitudes. Our attention was drawn to these phenomena while comparing ground magnetometer responses to measurements by particle and field ... |
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| Derivation of a Self-Consistent Auroral Oval Model Using the Auroral Boundary Index |
JUN 2004 |
110 pages |
| Authors:
Keith A. Anderson; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
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| The position and intensity of the auroral oval has many implications for the Air Force from determining the effects of incoming electron flux on DoD systems to modeling the ionosphere to exploit current HF communications capabilities. The auroral morphology is a good indicator of the level at which space weather and its near-Earth consequences are occurring, and thus it is important to develop an auroral prediction model. However, since no ... |
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| An Analysis of Airship Acceleration Dynamics for Airborne Gravimetry |
12 JAN 2004 |
21 pages |
| Authors:
Mary E. Peters; John M. Brozena; Robert T. Liang; NAVAL RESEARCH LAB WASHINGTON DC MARINE PHYSICS BRANCH
|
| A Honeywell three-axis inertial accelerometer was placed on board a Skyship 600B and acceleration data were recorded during the flight. Weather conditions during the flight were windy and turbulent, considered to be near the upper limits of this airship's operational envelope. Power spectra were computed from the acceleration data and showed favorable fall-off at high frequencies, but high power at low frequencies, as compared to a large, multi-engine aircraft used ... |
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| Paleomagnetism of Basaltic Lava Flows in Coreholes ICPP-213, ICPP-214, ICPP-215, and USGS 128 Near the Vadose Zone Research Park, Idaho Nuclear Technology and Engineering Center, Idaho National Engineering and Environmental Laboratory, Idaho |
OCT 2003 |
21 pages |
| Authors:
Duane E. Champion; Theodore C. Herman; GEOLOGICAL SURVEY RESTON VA
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| A paleomagnetic study was conducted on basalt from 41 lava flows represented in about 2,300 ft of core from coreholes ICPP-213, ICPP-214, ICPP-215, and USGS 128. These wells are in the area of the Idaho Nuclear Technology and Engineering Center (INTEC) Vadose Zone Research Park within the Idaho National Engineering and Environmental Laboratory (INEEL). Paleomagnetic measurements were made on 508 samples from the four coreholes, which are compared to each ... |
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| The Space-Developed Dynamic Vertical Cutoff Rigidity Model and its Applicability to Aircraft Radiation Dose |
17 FEB 2003 |
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| Authors:
D. F. Smart; M. A. Shea; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| We have developed a dynamic geomagnetic vertical cutoff rigidity model that predicts the energetic charged particle transmission through the magnetosphere. Initially developed for space applications, we demonstrate. the applicability of this library of cutoff rigidity models for computing aircraft radiation dose. The world grids of vertical cutoff rigidities were obtained by particle trajectory tracing in a magnetospheric model. This reference set of world grids of vertical cutoff rigidities calculated for ... |
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| A Study of Magnetic Storm Current Systems by the Application of Wavelet Analysis to Ground-Based Magnetograms |
05 SEP 2002 |
136 pages |
| Authors:
William B. Cade III; UTAH STATE UNIV LOGAN DEPT OF PHYSICS
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| Ground-based magnetograms are used to measure the intensity of magnetic storms, yet the relative contributions of the current systems involved have been debated for decades. Wavelet analysis is a technique to analyze signals with complex content and is well suited to the analysis of time-series data. I applied wavelet analysis to ground magnetograms to extract information about magnetic storms current systems. The analysis showed three components at low- and mid-latitudes: ... |
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| Multi-Step Dst Development and Ring Current Composition Changes During the 4-6 Jun 1991 Magnetic Storm |
30 DEC 2001 |
66 pages |
| Authors:
J. U. Kozyra; M. W. Liemohn; C. R. Clauer; J. Ridley; M. F. Thomsen; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
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| The 4-6 June 1991 magnetic storm during solar maximum conditions is analyzed to investigate two observed features of magnetic storms: (1) ring current composition changes strongly correlated with Dst changes; and (2) multi- step ring current development. A kinetic ring current drift-loss model, driven by dynamic fluxes at the nightside outer boundary, simulated this storm interval. The majority of ions in the partial ring current pass through the inner magnetosphere ... |
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| The Effect of Electric Field Structure on Joule Heating II: An Expanded Data Set |
28 SEP 2001 |
13 pages |
| Authors:
David N. Walker; WIlliam E. Amatucci; Gurudas I. Ganguli; NAVAL RESEARCH LAB WASHINGTON DC
|
| Emissive probe and ion energy analyzer diagnostics have been used to deduce the effect of electric field scale size on ion temperature in space simulation of ion heating in a large vacuum chamber. Results suggest an increase in ion temperature as a function of electric field scale size but a limit proportional to mean free path. |
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| Spacecraft Charging: Observations and Relationship to Satellite Anomalies |
01 AUG 2001 |
24 pages |
| Authors:
J. F. Fennell; H. C. Koons; J. L. Roeder; J. B. Blake; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| Many studies have shown that satellite charging can cause anomalies on spacecraft. The SCATHA (Spacecraft Charging AT High Altitude) satellite was flown to determine the conditions and document the existence of satellite charging. It was instrumented to measure charging and to detect electrostatic discharges that occurred. Discharges were observed and could be characterized as either surface or internal charging related. More recently, observations were made of charging on a high-inclination ... |
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| Identification of Submerged Side Scan Sonar and Magnetic Targets Naval Station Pascagoula, Mississippi |
JUN 2001 |
65 pages |
| Authors:
Michael C. Krivor; PANAMERICAN CONSULTANTS INC MEMPHIS TN
|
| From January 16-24, 2001, archaeologists from Panamerican Consultants, Inc. of Memphis, Tennessee conducted an intensive remote-sensing refinement survey and diver investigations of three magnetic anomalies and six sidescan targets located within Pascagoula Harbor, Jackson County, Mississippi. The purpose of the survey was to determine if any of the anomalies represent potentially significant submerged cultural resources eligible for listing on the National Register of Historic Places and which subsequently might require ... |
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| Energy Content in the Stormtime Ring Current |
10 MAR 2001 |
31 pages |
| Authors:
N. E. Turner; D. N. Baker; T. L. Pulkkimen; J. L. Roeder; J. F. Funnell; V. K. Jordanova; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
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| Due to the important role the ring current plays in magnetospheric energetics, it is essential to understand its strength and evolution in disturbed times. There are currently three main methods for deducing the strength of the ring current: measuring ground magnetic perturbations, measuring high-altitude magnetic perturbations, or directly measuring ring current particles. The use of ground magnetometers is the most convenient, and many use the ground magnetometer-derived Dst index as ... |
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| Ring Current Ion Composition during Solar Minimum and Rising Solar Activity: POLAR/CAMMICE/MICS Results |
28 FEB 2001 |
47 pages |
| Authors:
T. I. Pulkkinen; N. Ganushkina; D. N. Baker; N. E. Turner; J. F. Fennell; AEROSPACE CORP EL SEGUNDO CA
|
| This report shows statistical results of the ring current ion composition and its variability as a function of solar cycle and magnetospheric activity. Spin-averaged energetic particle (1-200 keV) measurements from the POLAR/CAMMICE/MICS instrument are combined with geomagnetic indices as well as solar wind and IMF observations from the WIND spacecraft during a period from September 1996 to March 1999. The statistics are performed both for time- averaged values for all ... |
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| Substorms and Magnetic Storms From the Satellite Charging Perspective |
28 FEB 2001 |
30 pages |
| Authors:
J. F. Fennell; H. C. Koons; J. L. Roeder; J. B. Blake; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| Sub storms and magnetic storms generate significant space weather effects in the inner magnetosphere. They change the dose rates experienced by satellites in many orbits and are directly linked to the occurrence of satellite charging. Substorms inject hot plasma into the nightside magnetosphere. The drifting electron component of this hot plasma can charge the surfaces of the satellites, leading to electrostatic discharges and associated satellite anomalies and sometimes failures. These ... |
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| Dawn/Dusk Dropouts Due to Storms/Substorms Near the Outer Radiation Belt: Observations From CRRESS |
20 SEP 2000 |
11 pages |
| Authors:
C. G. Mouikis; A. Korth; R. W. Friedel; J. Fennel; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| We investigate particle dropout events from the dawn flank of the magnetosphere as observed from a variety of instruments on board the CRRES satellite. All dropouts are observed at magnetic latitudes more than 100 above the magnetic equator. Plasma and energetic electron and ion data help us establish the boundary regimes being sampled. During these events, the magnetic field shows a dramatic change in the ... |
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| The Effect of Electric Field Structure on Joule Heating |
31 MAY 2000 |
18 pages |
| Authors:
D. N. Walker; W. E. Amatucci; G. Ganguli; NAVAL RESEARCH LAB WASHINGTON DC
|
| We have recently performed a detailed characterization of ion Joule heating perpendicular to an axial magnetic field in the laboratory in a simulated ionospheric plasma environment which contains localized electric field structuring. Since Joule heating is often regarded as an important mechanism contributing to energization of outflowing heavy ions observed by higher altitude auroral satellites, this work has particular relevance to space physics issues; and, to our knowledge, has not ... |
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| Testing of the New USGS K Index Algorithm at Bear Lake Observatory |
MAR 2000 |
123 pages |
| Authors:
Ariel O. Acebal; AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH SCHOOL OF ENGINEERING
|
| The K index was developed by Bartels in 1939 as an estimate of the level of geomagnetic activity caused by the Sun. This index was computed manually every three hours at geomagnetic observatories using the magnetic traces of the surface planetary magnetic field. In 1991, the International Association of Geomagnetism and Aeronomy approved four additional methods to compute the K index; all of them were ... |
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| An Investigation of Variable Time Interval "K-like" Geomagnetic Indices |
16 DEC 1999 |
134 pages |
| Authors:
Devin J. Della-Rose; UTAH STATE UNIV LOGAN
|
| The 3-hour planetary K index derivative, Kp, is designed to measure irregular fluctuations in the Earth's magnetic field due to currents in the magnetosphere-ionosphere system. The index is widely used to drive empirical models of auroral particle precipitation, high-latitude convection patterns, thermospheric composition, and neutral winds. The 3-hour time interval of Kp makes it suitable for use as a parameter in thermospheric models, since the ... |
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| Dawn/Dusk Dropouts due to Storms/Sub storms Near the Outer Radiation Belt: Observations from CRRES |
30 SEP 1999 |
9 pages |
| Authors:
C. G. Mouikis; A. Korth; R. H. Friedel; J. F. Fennell; AEROSPACE CORP EL SEGUNDO CA ENGINEERING AND TECHNOLOGY GROUP
|
| We investigate the particle dropout events from the dawn flank of the magnetosphere as observed from a variety of instruments on board the CRRES satellite. All dropouts are observed at magnetic latitudes more than 100 above the magnetic equator. Plasma and energetic electron and ion data help us establish the boundary regimes being sampled. During these events, the magnetic field shows a dramatic change in the ... |
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| Distributions of Magnetic Field Variations, Differences and Residuals |
FEB 1999 |
|
| Authors:
J. Watermann; J. Lam; SACLANT UNDERSEA RESEARCH CENTRE LA SPEZIA (ITALY)
|
| Temporal and spatial variations of the geomagnetic field were recorded in different geographic areas, using arrays of seven tri-axial magnetometers which resided on the sea bottom in 50-150 m depth for periods up to 16 days. The different geographic areas are characterized by different levels of the mean ambient magnetic noise. We discuss briefly data from a magnetically quiet area and then focus on a coastal ... |
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| Survey of Ring Current Composition During Magnetic Storms |
15 FEB 98 |
12 pages |
| Authors:
M. Grande; C. H. Perry; A. Hall; J. Fennell; B. Wilken; AEROSPACE CORP EL SEGUNDO CA TECHNOLOGY OPERATIONS
|
| During geomagnetic storms, the ring current is substantially modified and intensified. We use data from the MICS instrument on CRRES to investigate composition changes in magnetospheric ions in the energy range 20-400 keV/e. These are related to the Dst signature of the storm. Long term survey plots of MICS data show that during storms there is an initial increase of ionospheric material at around L = ... |
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| Global Ground Tomography |
11 DEC 1997 |
117 pages |
| Authors:
T. Wallace; D. MacEnany; D. Papadopoulos; R. Singerman; ADVANCED POWER TECHNOLOGIES INC WASHINGTON DC
|
| The results of the first year of the Global Ground Tomography program for low frequency electromagnetic imaging and characterization of underground structures are presented. |
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| A Magnetospheric Neutral Sheet-Oriented Coordinate System for MSM and MSFM Applications |
31 JUL 97 |
55 pages |
| Authors:
R. V. Hilmer; BOSTON COLL CHESTNUT HILL MA INST FOR SCIENTIFIC RESEARCH
|
| We develop an analytic magnetospheric neutral sheet oriented coordinate system which depends on the Earth's dipole tilt angle, psi, and the geomagnetic activity index Kp. With an orientation similar to that of the GSM coordinate system, this non-orthogonal coordinate system contains coordinate surfaces (at constant Z' values) which conform to a shape approximating that of the magnetic neutral sheet. By more accurately representing a point's location relative to the magnetic ... |
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| The Effects of Magnetic Storm Phases on F-Layer Irregularities from Auroral to Equatorial Latitudes |
30 JUN 97 |
4 pages |
| Authors:
Jules Aarons; Michael Mendillo; BOSTON UNIV MA CENTER FOR SPACE PHYSICS
|
| With scintillation data collected at both high and equatorial latitudes for a series of magnetic storms, we are searching for means of identifying the parameters at high latitudes which produce effects at equatorial latitudes. We seek to understand the physics of development of irregularities both at high and at equatorial latitudes. The measurement of parameters which are necessary and sufficient to develop the irregularities can be used to forecast and ... |
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| Models of the Near-Space Geophysical Environment |
30 JUN 97 |
55 pages |
| Authors:
Edward C. Robinson; James N. Bass; Krishin H. Bhavnani; Carl A. Hein; William J. McNeil; PHILLIPS LAB HANSCOM AFB MA
|
| This report provides descriptions of environmental models used in the near-earth environment for the analysis of earth-based and satellite data. Included are models of the ionosphere, atmosphere, radiation belt, Earth's magnetic field, and orbital prediction. These models are used at PL for a variety of purposes, in particular, for the analysis of experimental data obtained from ground based instruments and, where applicable, instruments carried on balloons, rockets, and satellites. Some ... |
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| Magnetospheric Dynamics: A Comprehensive Study |
MAR 97 |
22 pages |
| Authors:
Dennis E. Delorey; M. P. Hagan; BOSTON COLL CHESTNUT HILL MA INST FOR SCIENTIFIC RESEARCH
|
| This report is comprised of thirty three abstracts of papers presented or published in the first 12 month period of this contract. They are selected as being of the highest scientific interest of all such presentations or publications occurring under this contract during the year. |
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| Thermospheric Density Variability and Forecast Model Development |
15 JAN 97 |
27 pages |
| Authors:
Jeffrey M. Forbes; Timothy Fuller-Rowell; COLORADO UNIV AT BOULDER DEPT OF AEROSPACE ENGINEERING SCIENCES
|
| Thermospheric densities derived from SETA-1, SETA-2 and SETA-3 accelerometer data, and cross track winds from SETA-1, were analyzed to determine the nature of latitudinal structures at latitudes greater than 45 degrees. Distinct dependencies on magnetic activity level, local time, hemisphere and season are revealed. Empirical models such as MSIS or J70 do not represent the observed high latitude structures. The Coupled Thermosphere Ionosphere Model (CTIM), however, is able to reproduce ... |
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| Effects of a Cross-Tail Magnetic Field on the Equilibrium Structure of the Quiet-Time Magnetotail |
12 JAN 97 |
185 pages |
| Authors:
Daniel L. Holland; ILLINOIS STATE UNIV NORMAL
|
| As the publication record suggests during the tenure of the grant we have investigated a number of topics relevant to nonlinear dynamics and equilibrium structures in the magnetotail. Some of the initial goals of the program were modified so as to allow for more active participation of undergraduate students in the research. We are still in the process of completing some of the self consistent magnetotail equilibrium calculations. A brief ... |
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| An Expanded Altitude Algorithm for Computing Altitude-Dependent Corrected Geomagnetic Coordinates |
15 OCT 96 |
28 pages |
| Authors:
C. A. Hein; K. H. Bhavnani; RADEX INC BEDFORD MA
|
| A revised algorithm covering an expanded range of altitudes is described for computing altitude dependent corrected geomagnetic (CGM) coordinates from geocentric coordinates (and, where it exists, the inverse) using spherical harmonics. The original version was based upon the IGRF 90 magnetic field model, and was recently upgraded using the IGRF 95 model. In common with the two previous versions, the revised algorithm uses a tenth order spherical harmonic fit to ... |
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| Statistical Technique for Intermediate and Long-Range Estimation of 13- Month Smoothed Solar Flux and Geomagnetic Index |
SEP 1996 |
80 pages |
| Authors:
K. O. Niehuss; H. C. Euler Jr.; W. W. Vaughan; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HUNTSVILLE AL GEORGE C MARSHALL SPACE FLIGHT CENTER
|
| This report documents the Marshall Space Flight Center (MSFC) 13- month smoothed solar flux (F10.7) and geomagnetic index (Ap) intermediate (months) and long-range (years) statistical estimation technique, referred to as the MSFC Lagrangian Linear Regression Technique (MLLRT). Estimates of future solar activity are needed as updated input to upper atmosphere density models used for satellite and spacecraft orbital lifetime predictions. An assessment of the MLLRT computer ... |
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| The Effects of Magnetic Storm Phases on F-Layer Irregularities from Auroral to Equatorial Latitudes |
30 JUN 96 |
4 pages |
| Authors:
Jules Aarons; Michael Mendillo; BOSTON UNIV MA CENTER FOR SPACE PHYSICS
|
| Analysis of equatorial observations of GPS from stations on the magnetic equator and in the anomaly region allow us to begin to study the morphology of height of plumes and the occurrence pattern of thin layers of irregularities during years of low solar flux. Very high altitude plumes have been observed during magnetic storms in the data sets analyzed for 1993-1996. At high latitudes a storm expands the irregularity oval ... |
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| Solar Water Heating -- Guidance for Small Facilities |
MAY 96 |
7 pages |
| Authors:
Mike Rocha; NAVAL FACILITIES ENGINEERING SERVICE CENTER PORT HUENEME CA
|
| Water heating accounts for a substantial portion of energy use at many Federal facilities. Of the total energy used, approximately 18 percent in residential and 4 percent in commercial buildings is for water heating; that percentage may be much higher for buildings with laundries, kitchens, showers, or swimming pools. Nearly all hot water in the United States is heated directly or indirectly through the combustion of some fossil fuel. Because ... |
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| FY 97 Geophysics Technology Area Plan |
MAY 96 |
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| Authors:
AIR MATERIEL COMMAND WRIGHT-PATTERSON AFB OH
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| The Effects of Magnetic Storm Phases on F-Layer Irregularities from Auroral to Equatorial Latitudes |
31 MAR 96 |
5 pages |
| Authors:
Jules Aarons; Michael Mendillo; BOSTON UNIV MA CENTER FOR SPACE PHYSICS
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| Studies in conjunction with J. Clynch of the Naval Post Graduate School showed that very severe magnetic storms have affected GPS reception at auroral latitudes. Analysis of auroral data indicates that some receivers ride through high amplitude scintillation. Receiver characteristics are discussed which keep track so that short term fades do not affect lock immediately. |
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| Magnetospheric Morphology and Dynamics: Specification of the Near-Earth Operational Environment |
03 JAN 96 |
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| Authors:
Ching-I. Meng; JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB
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Geomagnetism
