Ionospheric Monitoring and Specification Utilizing Data From the Defense Meteorological Satellite Program

<p>In this study, TEC measurements from METOP (Meteorological Operational) satellites are used together with a tomographic algorithm to estimate electron density distributions during geomagnetic storm events. The proposed method is applied during four geomagnetic storms to check the tomographic capabilities for space weather monitoring. The developed method was capable to successfully capture and reconstruct well-known enhancement and decrease of electron density during the geomagnetic storms. The comparison with in-situ electron densities from DMSP (Defense Meteorological Satellite Program) satellites has shown an improvement around 11% and a better plasma description compared to the background. Our study also reveals that the plasmasphere TEC contribution to ground-based TEC may vary 10 to 60% during geomagnetic storms, and the contribution tends to reduce during the storm-recovery phase.</p>

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Subvisual Cirrus

Cirrus ◽

10.1093/oso/9780195130720.003.0016 ◽

2002 ◽

Author(s):

David K. Lynch ◽

Kenneth Sassen

Keyword(s):

World War Ii ◽

Solar Limb ◽

Stratospheric Aerosol ◽

Defense Meteorological Satellite Program ◽

Passive Sensors ◽

The Tropics ◽

Anvil Cirrus ◽

High Clouds ◽

Meteorological Satellite

Starting during World War II, pilots flying high over the tropics reported “a thin layer of cirrus 500ft above us”. Yet as they ascended, they still observed more thin cirrus above them, leading to the colloquialism “cirrus evadus.” With the coming of lidar in the early 1960s, rumors and unqualified reports of subvisual cirrus were replaced with validated detections, in situ sampling, and the first systematic studies (Uthe 1977; Barnes 1980, 1982). Heymsfield (1986) described observations over Kwajalein Atoll in the western tropical Pacific Ocean, where pilots and lidars could clearly see the cloud but DMSP (U.S. Defense Meteorological Satellite Program) radiance measurements and ground observers could not. The term “subvisual” is a relatively recent appellation. Prior terminology included cirrus haze, semitransparent cirrus, subvisible cirrus veils, low density clouds, fields of ice aerosols, cirrus, anvil cirrus, and high altitude tropical (HAT) cirrus. Subvisual cirrus clouds (SVC) are widespread (Winker and Trepte 1998; see chapter 12, this volume) and virtually undetectable with existing passive sensors. Orbiting solar limb occupation systems such as the Stratospheric Aerosol and Gas Experiment (SAGE) can detect these clouds, but only by looking at them horizontally where the optical depths are significant. SVC appear to affect climate primarily by heating the planet, though to what extent this may happen is unknown. Much of what we know is based on work by Heymsfield (1986), Platt et al. (1987), Sassen et al. (1989, 1992), Flatau et al. (1990), Liou et al. (1990), Hutchinson et al. (1991, 1993), Dalcher (1992), Sassen and Cho (1992), Takano et al. (1992), Lynch (1993), Schmidt et al. (1993), Schmidt and Lynch (1995), and Winker and Trepte (1998). SVC are defined as any high clouds composed primarily of ice (WMO 1975) and whose vertical visible optical depth is 0.03 or less (Sassen and Cho 1992). Such clouds are usually found near the tropopause and are less than about 1 km thick vertically. SVC do not appear to be fundamentally different from ordinary, optically thicker cirrus. They do, however, differ from average cirrus by being colder (-50-90°C), thinner (<0.03 optical depths at 0.694 μm), and having smaller particles (typically about <50μm diameter).

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A Comparative Study of Estimating Auroral Electron Energy from Ground-Based Hyperspectral Imagery and DMSP-SSJ5 Particle Data

Remote Sensing ◽

10.3390/rs12142259 ◽

2020 ◽

Vol 12 (14) ◽

pp. 2259

Author(s):

Wanqiu Kong ◽

Zejun Hu ◽

Jiaji Wu ◽

Tan Qu ◽

Gwanggil Jeon

Keyword(s):

Spectral Data ◽

Brute Force ◽

Characteristic Energy ◽

Particle Detectors ◽

Zhongshan Station ◽

Defense Meteorological Satellite Program ◽

Auroral Electron ◽

Auroral Electrons ◽

Meteorological Satellite ◽

Strong Linear Relationship

Aurora, the spectacular phenomenon commonly occurring in high latitudes, is caused by the precipitation of energetic particles penetrating the Earth’s atmosphere. Being the result of solar-terrestrial interactions, electron precipitation significantly contributes to auroral production. To evaluate its magnitude, a physical quantity describing the characteristics of precipitating auroral electrons—their characteristic energy—is adopted. In this paper, this quantity is derived from joint data observed by the ground-based auroral spectroscopic imager located in Antarctica Zhongshan Station and the particle detectors “Special Sensor J5 (SSJ5)” on the Defense Meteorological Satellite Program (DMSP) satellites. A postprocessing scheme of ground-based spectral data is proposed to infer the characteristic energy that successively uses classical brute-force, recursive brute-force and self-consistent approximation strategies for step-up speed improvement. Then, the inferred characteristic energies are compared to the average energies calibrated from the relevant electron data detected by SSJ5 to confirm whether this inference is valid. Regarding DMSP F18/SSJ5, these two energy estimations about auroral electrons deviate slightly from each other and show a strong linear relationship. It sheds light on further applications of the valuable aurora spectral data.

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Occurrence of Equatorial Plasma Bubbles during Intense Magnetic Storms

International Journal of Geophysics ◽

10.1155/2011/401858 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10 ◽

Cited By ~ 11

Author(s):

Chao-Song Huang

Keyword(s):

Electric Field ◽

Magnetic Storms ◽

Ion Density ◽

Plasma Bubbles ◽

Defense Meteorological Satellite Program ◽

Equatorial Plasma Bubbles ◽

Evening Sector ◽

Plasma Depletions ◽

Meteorological Satellite ◽

The Imf

An important issue in low-latitude ionospheric space weather is how magnetic storms affect the generation of equatorial plasma bubbles. In this study, we present the measurements of the ion density and velocity in the evening equatorial ionosphere by the Defense Meteorological Satellite Program (DMSP) satellites during 22 intense magnetic storms. The DMSP measurements show that deep ion density depletions (plasma bubbles) are generated after the interplanetary magnetic field (IMF) turns southward. The time delay between the IMF southward turning and the first DMSP detection of plasma depletions decreases with the minimum value of the IMFBz, the maximum value of the interplanetary electric field (IEF)Ey, and the magnitude of the Dst index. The results of this study provide strong evidence that penetration electric field associated with southward IMF during the main phase of magnetic storms increases the generation of equatorial plasma bubbles in the evening sector.

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