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Calculation of the extreme ultraviolet radiation of the earth's plasmasphere

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Science China(Technological Sciences) 2010年第1期53卷 200-205页

作者： FOK Mei-Ching nasa goddard space Flight Center GreenbeltMD 20771USA

The dynamic global core plasma model(DGCPM) is used in this paper to calculate the He+ density distribution of the Earth's plasmasphere and to investigate the configurations and 30.4 nm radiation properties of the *** comparisons between the simulation results and IMAGE mission observations show:That the equatorial structure of the plasmapause is mainly located near 5.5 RE and the typical scale of plasmasphere shrinking or expansion within 10 min is approximately 0.1 RE;that the plasmaspheric shoulders are formed and rotate noon-ward from the dawn sector under the conditions of strong southward turning of the interplanetary magnetic field(IMF);that the plasmaspheric plumes will rotate dawn-ward from the night sector and become narrow for the southward turning of the *** simulated images from the lunar orbit show that the plasmasphere locating within the geocentric distance of 5.5 RE corresponds to field of view(FOV) of 10.7°×10.7° for the moon-based EUV imager,and that the 30.4 nm radiation intensity of the plasmasphere is 0.1-11.4 *** plasmaspheric shoulders and plumes locating toward the moon-side are for the first time simulated with typical scale level of 0.1 RE from the side view of the *** simulated results provide an important theoretical basis for the lunar-based EUV camera design.

关键词： earth’s plasmasphere dynamic global core plasma model extreme ultraviolet radiation lunar-based imaging

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The neutron star zoo

Frontiers of physics 2013年第6期8卷 679-692页

作者： Alice K. Harding Astrophysics Science Division NASA Goddard Space Flight Center Greenbelt MD 20771 USA

Neutron stars are a very diverse population, both in their observational and their physical properties. They prefer to radiate most of their energy at X-ray and gamma-ray wavelengths. But whether their emission is powered by rotation, accretion, heat, magnetic fields or nuclear reactions, they are all different species of the same animal whose magnetic field evolution and interior composition remain a mystery. This article will broadly review the properties of inhabitants of the neutron star zoo, with emphasis on their high-energy emission.

关键词： stars neutron stars pulsars binary stars

Automatic sub-pixel co-registration of Landsat-8 Operational Land Imager and Sentinel-2A Multi-Spectral Instrument images using phase correlation and machine learning based mapping

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International Journal of Digital Earth 2017年第12期10卷 1253-1269页

作者： Sergii Skakun Jean-Claude Roger Eric F.Vermote Jeffrey G.Masek Christopher O.Justice Department of Geographical Sciences University of MarylandCollege ParkMDUSA nasa goddard space Flight Center Code 619 GreenbeltMDUSA nasa goddard space Flight Center Code 618 GreenbeltMDUSA

This study investigates misregistration issues between Landsat-8/Operational Land Imager and Sentinel-2A/Multi-Spectral Instrument at 30 m resolution,and between multi-temporal Sentinel-2A images at 10 m resolution using a phase-correlation approach and multiple transformation ***-registration of 45 Landsat-8 to Sentinel-2A pairs and 37 Sentinel-2A to Sentinel-2A pairs were *** correlation proved to be a robust approach that allowed us to identify hundreds and thousands of control points on images acquired more than 100 days ***,misregistration of up to 1.6 pixels at 30 m resolution between Landsat-8 and Sentinel-2A images,and 1.2 pixels and 2.8 pixels at 10 m resolution between multi-temporal Sentinel-2A images from the same and different orbits,respectively,were *** non-linear random forest regression used for constructing the mapping function showed best results in terms of root mean square error(RMSE),yielding an average RMSE error of 0.07±0.02 pixels at 30 m resolution,and 0.09±0.05 and 0.15±0.06 pixels at 10 m resolution for the same and adjacent Sentinel-2A orbits,respectively,for multiple tiles and multiple conditions.A simpler 1st order polynomial function(affine transformation)yielded RMSE of 0.08±0.02 pixels at 30 m resolution and 0.12±0.06(same Sentinel-2A orbits)and 0.20±0.09(adjacent orbits)pixels at 10 m resolution.

关键词： Sub-pixel co-registration phase correlation misregistration Landsat-8 Sentinel-2 machinelearning random forest

A Note on the Relationship Between Temperature and Water Vapor over Oceans, Including Sea Surface Temperature Effects

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Advances in Atmospheric Sciences 2006年第1期23卷 141-148页

作者： C.-L. SHIE W.-K. TAO J. SIMPSON goddard Earth Sciences and Technology Center University of MarylandBaltimore CountyBaltimoreMaryland 21250USA Laboratory for AtmospheresNASA Goddard Space Flight CenterGreenbeltMaryland 20771USA Laboratory for Atmospheres NASA Goddard Space Flight CenterGreenbeltMaryland 20771USA

An ideal and simple formulation is successfully derived that well represents a quasi-linear relationship found between the domain-averaged water vapor, Q （ram）, and temperature, T （K）, fields for the three tropical oceans （i.e., the Pacific, Atlantic and Indian Oceans） based on eleven GEOS-3 [goddard Earth Observing System （EOS） Version-3] global re-analysis monthly products. A Q - T distribution analysis is also performed for the tropical and extra-tropical regions based on in-situ sounding data and numerical simulations [GEOS-3 and the goddard Cumulus Ensemble （GCE） model]. A similar positively correlated Q - T distribution is found over the entire oceanic and tropical regions; however, Q increases faster with T for the former region. It is suspected that the tropical oceans may possess a moister boundary layer than the Tropics. The oceanic regime falls within the lower bound of the tropical regime embedded in a global, curvilinear Q - T relationship. A positive correlation is also found between T and sea surface temperature （SST）; however, for one degree of increase in T, SST is found to increase 1.1 degrees for a warmer ocean, which is slightly less than an increase of 1.25 degrees for a colder ocean. This seemingly indicates that more （less） heat is needed for an open ocean to maintain an air mass above it with a same degree of temperature rise during a colder （warmer） season [or in a colder （warmer） region]. Q and SST are also found to be positively correlated. Relative humidity （RH） exhibits similar behaviors for oceanic and tropical regions. RH increases with increasing SST and T over oceans, while it increases with increasing T in the Tropics. RH, however, decreases with increasing temperature in the extratropics. It is suspected that the tropical and oceanic regions may possess a moister local boundary layer than the extratropics so that a faster moisture increase than a saturated moisture increase is favored for the former regions. T, Q, saturated water v

关键词： moisture temperature relationship quasi-equilibrium states Tropics oceans

Optical Study of Bandedge Blue-Shift in AlGaN/GaN Double Quantum Wells

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Chinese Physics Letters 1997年第9期14卷 708-711页

作者： YANG Kai SHEN Bo ZHANG Rong ZHOU Yu-gang CHEN Zhi-zhong CHEN Peng ZHENG You-dou HUANG Zhen-chun Department of Physics Nanjing Universitx Nanjing 210093 nasa goddard space Flight Center Code 718GreenbeltMD 20771USA

Optical properties of AlGaN/GaN double quantum wells grown by metalorganic chemical vapor deposition are *** wide-angle and small angle x-ray diffraction spectra show high crystalline quality of the *** transmission and cathodoluminescence spectra exhibit that there is a blue shift of the energy bandedge in the AlGaN/GaN double quantum wells comparing to that of bulk *** experimental data are compared to theoretical calculation based on the finite square well model and a confined particle transitions are *** observed energy shift which differs from calculated values of ground state electron to heavy hole transition is attributed to strain in the AlGaN/GaN system.

关键词： AlGaN/GaN Optical Quantum

Degree One Loading by Pressure Variations at the CMB

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Journal of Earth Science 2013年第5期24卷 736-749页

作者： Ming Fang Bradford H Hager Weijia Kuang Department of Earth Atmospheric & Planetary Sciences Massachusetts Institute of Technology Planetary Geodynamics Laboratory NASA Goddard Space Flight Center

Hemispherical asymmetry in core dynamics induces degree-1 pressure variations at the core mantle boundary （CMB）, which in turn deforms the overlaying elastic mantle, at the same time keeps center of mass of the whole Earth stationary in space. We develop a systematic procedure to deal with the degree-1 CMB pressure loading. We find by direct calculation a surprisingly negative load Love number h1=-1.425 for vertical displacement. Further analysis indicates that the negative hi corre- sponds to thickening above the positive load that defies intuition that pressure inflation pushes over- laying material up and thins the enveloping shell. We also redefine the pressure load Love numbers in general to enable comparison between the surface mass load and the CMB pressure load for the whole spectrum of harmonic degrees. We find that the gravitational perturbations from the two kinds of loads at degrees n〉l are very similar in amplitude but opposite in sign. In particular, if the CMB pressure variation at degree 2 is at the level of -1 hpa/yr （1 cm water height per year）, it would perturb the variation of Earth＇s oblateness, known as the J2, at the observed level.

关键词： Degree One Loading by Pressure Variations at the CMB MRSP

Resolving SSM/I-Ship Radar Rainfall Discrepancies from AIP-3

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Advances in Atmospheric Sciences 2005年第6期22卷 903-914页

作者： Song YANG Eric A. SMITH School of Computational Sciences George Mason University Fairfax VA USA nasa/goddard space Flight Center Greenbelt MD USA

The third algorithm intercomparison project （AIP-3） involved rain estimates from more than 50 satellite rainfall algorithms and ground radar measurements within the Intensive Flux Array （IFA） over the equatorial western Pacific warm pool region during the Tropical Ocean Global Atmosphere coupled Ocean-Atmosphere Response Experiment （TOGA COARE）. Early results indicated that there was a sys- tematic bias between rainrates from satellite passive microwave and ground radar measurements. The mean rainrate from radar measurements is about 50% underestimated compared to that from passive microwave-based retrieval algorithms. This paper is designed to analyze rain patterns from the Florida State University rain retrieval algorithm and radar measurements to understand physically the rain discrep- ancies. Results show that there is a clear range-dependent bias associated with the radar measurements. However, this range-dependent systematical bias is almost eliminated with the corrected radar rainrates. Results suggest that the effects from radar attenuation correction, calibration and beam filling are the major sources of rain discrepancies. This study demonstrates that rain retrievals based on satellite mea- surements from passive microwave radiometers such as the Special Sensor of Microwave Imager （SSM/I） are reliable, while rain estimates from ground radar measurements are correctable.

关键词： rainfall SSM/I radar satellite microwave measurements

Origins of perturbations in dayside equatorial ground magnetograms

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Earth and Planetary Physics 2024年第1期8卷 215-221页

作者： Syau-Yun W.Hsieh David G.Sibeck The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA nasa goddard space Flight Center GreenbeltMarylandUSA

To determine the cause(s)of perturbations seen in dayside equatorial ground magnetograms,we conducted a systematic survey of simultaneous ground-based and geosynchronous satellite-based observations during the 90-day period from December 1,2020 to February 28,*** examined Huancayo ground magnetometer observations from 14:00:00 to 20:00:00 UT each day,during which Huancayo passed through local *** those data we chose perturbation events selected on the basis of large(>20 nT)event amplitude and classified the selected events as responding primarily to solar wind pressure,or to variations in the north/south component of the interplanetary magnetic field(IMF Bz),or perhaps in part to *** results show that an equivalent number of events were identified for each model during this 90-day *** in the lagged solar wind dynamic pressure routinely correspond to nearly simultaneous sudden impulses recorded at both geosynchronous orbit and on the *** in IMF Bz produce erosion signatures at geosynchronous orbit and can correspond to ground events if lag times for reconnection to enhance convection in the magnetosphere are taken into account.

关键词： dayside magnetosphere dayside equatorial ionosphere geosynchronous magnetic field

1982～1996年亚洲热带夏季风建立迟早的探讨(Ⅰ)热带季风环流的主要特征和季风建立指数

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中山大学学报（自然科学版） 2000年第3期39卷 91-96页

作者：贺海晏温之平简茂球隋中兴中山大学大气科学系广东广州510275 nasa goddard space flightcenter

利用NCEP再分析的 1982～ 1996年的风场和高度场资料 ,分析讨论了亚洲热带夏季风环流的若干基本特征 ;从季风环流的主要特征出发 ,定义了一个季风建立指数 ;计算、确定和分析了东亚季风区和印度季风区 15年平均的季风建立时间 .结果表... 详细信息

利用NCEP再分析的 1982～ 1996年的风场和高度场资料 ,分析讨论了亚洲热带夏季风环流的若干基本特征 ;从季风环流的主要特征出发 ,定义了一个季风建立指数 ;计算、确定和分析了东亚季风区和印度季风区 15年平均的季风建立时间 .结果表明 ,在 1982～ 1996年期间 ,平均而言 ,东亚热带季风 5月第 4候建立 ,维持到 10月第 2候 ;印度季风 6月第 2候建立 ,比南海热带季风晚约 4候 ,持续至 9月第

关键词：亚洲热带夏季风环流气候特征建立指数