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Response of photoelectron peaks in the Martian ionosphere to solar EUV/X-ray irradiance

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Earth and Planetary Physics 2020年第4期4卷 390-395页

作者： XiaoShu Wu Jun Cui YuTian Cao WeiQin Sun Qiong Luo BinBin Ni National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519082China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430074China

An important population of the dayside Martian ionosphere are photoelectrons that are produced by solar Extreme Ultraviolet and X-ray ionization of atmospheric neutrals.A typical photoelectron energy spectrum is characterized by a distinctive peak near 27 eV related to the strong solar HeⅡ emission line at 30.4 nm,and an additional peak near 500 eV related to O Auger ionization.In this study,the extensive measurements made by the solar Wind Electron Analyzer on board the recent Mars Atmosphere and Volatile Evolution spacecraft are analyzed and found to verify the scenario that Martian ionosphere photoelectrons are driven by solar radiation.We report that the photoelectron intensities at the centers of both peaks increase steadily with increasing solar ionizing flux below 90 nm and that the observed solar cycle variation is substantially more prominent near the O Auger peak than near the HeⅡ peak.The latter observation is clearly driven by a larger variability in solar irradiance at shorter wavelengths.When the solar ionizing flux increases from 1 mW·m^-2 to 2.5 mW·m^-2,the photoelectron intensity increases by a factor of 3.2 at the HeⅡ peak and by a much larger factor of 10.5 at the O Auger peak,both within the optically thin regions of the Martian atmosphere.

关键词： Mars ionosphere photoelectron solar irradiance MAVEN

Distribution of solar irradiance on Inclined Surfaces Due to the Plane of the Ground

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Journal of Power and Energy Engineering 2014年第7期2卷 1-10页

作者： Teolan Tomson Henrik Voll Institute of Materials Science Tallinn University of Technology(TUT)TallinnEstonia Department of Environmental Engineering Tallinn University of Technology(TUT)TallinnEstonia

Measurements of solar radiation are ordinarily made on horizontal planes recording global, diffuse and reflected components. The beam component and distribution of the global radiation on tilted planes can be calculated via the said components, as the position of the Sun in the sky’s sphere is known. Another ordinary procedure is measuring beam and diffuse components and calculating global radiation. These measurements require stationary equipment and in such a way it is difficult to study the influence of different grounds on the distribution of radiation on the inclined surfaces due to the ground. This distribution has some importance in civil engineering, but it is not popular in the field of solar radiation investigations. Present paper shows how this distribution can be calculated measuring only global irradiance on the horizontal and vertical planes. Such an approach, which is valid in clear-sky and overcast conditions, allows the use of a portable measuring device and studies of different grounds. The coincidence of the calculated values with the actual is good, except for snow-cover and discrete cloud, which do not correspond to the isotropic sky and ground models.

关键词： solar irradiance Hanging Down Facade Ground Influence

Delayed Antarctic melt season reduces albedo feedback

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National Science Review 2023年第9期10卷 236-246页

作者： Lei Liang Huadong Guo Shuang Liang Xichen Li John C.Moore Xinwu Li Xiao Cheng Wenjin Wu Yan Liu Annette Rinke Gensuo Jia Feifei Pan Chen Gong Key Laboratory of Digital Earth Science Aerospace Information Research Institute Chinese Academy of Sciences 2. International Research Center of Big Data for Sustainable Development Goals Institute of Atmospheric Physics Chinese Academy of Sciences College of Global Change and Earth System Science Beijing Normal University Arctic Centre University of Lapland CAS Center for Excellence in Tibetan Plateau Earth Sciences School of Geospatial Engineering and Science Sun Yat-sen University Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Department of Geography University of North Texas

Antarctica’ s response to climate change varies greatly both spatially and temporally.Surface melting impacts mass balance and also lowers surface albedo.We use a 43-year record(from 1978 to 2020) of Antarctic snow melt seasons from space-borne microwave radiometers with a machine-learning algorithm to show that both the onset and the end of the melt season are being delayed.Granger-causality analysis shows that melt end is delayed due to increased heat flux from the ocean to the atmosphere at minimum sea-ice extent from warming oceans.Melt onset is Granger-caused primarily by the turbulent heat flux from ocean to atmosphere that is in turn driven by sea-ice variability.Delayed snowmelt season leads to a net decrease in the absorption of solar irradiance,as a delayed summer means that higher albedo occurs after the period of maximum solar radiation,which changes Antarctica’s radiation balance more than sea-ice cover.

关键词： Antarctic ice sheet snowmelt season delay sea ice solar irradiance

Development and comparison of local solar split models on the example ofCentral Europe

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能源与人工智能(英文)

能源与人工智能(英文) 2023年第2期12卷 31-43页

作者： E.Schlager G.Feichtinger H.Gursch Know-Center GmbH Inffeldgasse 13/68010 GrazAustria

solar radiation influences many and diverse fields like energy generation, agriculture and building operation.Hence, simulation models in these fields often rely on precise information about solar radiation. Measurementsare often restricted to global irradiance, whereby measurements of its single components, direct and diffuseirradiance, are sparse. However, information on both, the direct and diffuse irradiance, is necessary forsimulation models to work reliably. In this study, solar separation models are developed using 10-min trainingdata from two different locations in Austria. Direct horizontal irradiance is predicted via regressing the directfraction using several objective functions. The models are first trained on a data set including data from bothlocations, and evaluated regarding root mean squared deviation (RMSD), mean bias deviation (MBD), andcoefficient of determination (R2) on measured and estimated direct normal irradiance. The two best performing models are then selected for further analysis. This analysis comprises of an evaluation of the models per season,transferability of trained modes between two locations in Austria, a transferability and generalisability studyconducted for four more locations in Central Europe, and a comparison with the trusted Engerer model. Thesolar separation model with polynomial terms up to order three and Ridge regularisation outperforms thesecond model based a logistic term in combination with mixed quadratic terms as well as the Engerer model.

关键词： solar irradiance Direct normal irradiance solar separation model solar regression solar model transferability Seasonality

Potentiality of solar Photovoltaic Energy in Paraiba, Brazil, and the Relation with Sustainable Development

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Journal of Geoscience and Environment Protection 2023年第5期11卷 135-149页

作者： João Ramos da Silva Júnior Hermes Alves de Almeida Postgraduate Program in Regional Development State University of Paraiba (UEPB) Campina Grande Brazil Department of Geography State University of Paraiba (UEPB) Campina Grande Brazil

The use of non-renewable energy has been a major environmental concern and, therefore, there is a need to look for other renewable energy sources, especially photovoltaic’s. In view of this, an attempt was made to quantify the potential of solar irradiance in the State of Paraiba, as an alternative source for conversion and use in electrical energy, these determinations being the main objectives. Global solar irradiance and solar photovoltaic data were extracted from scientific publications and/or made available on the websites of the National Institute of Meteorology (INMET), the Ministry of Mines and Energy and the National Electric Energy Agency, among others. For the case study, semi-structured questionnaires were applied in different business establishments in Campina Grande, with questions related to socioeconomic aspects and photovoltaic technology. Data were analyzed using descriptive statistics criteria and using an Excel spreadsheet. The main results indicated that the Brazilian energy matrix is predominantly from renewable sources. The Northeast is the second region with the highest production of photovoltaic solar energy and the State of Paraiba occupies its fourth position in the generation of this type of energy. The option of photovoltaic technology is a promising alternative, especially for rural areas, where there is not always a conventional electricity grid. The high availability of solar energy in northeastern Brazil, in almost all months of the year, especially in the state of Paraiba, demonstrates the existence of a high potential to generate electricity from photovoltaic systems. This technology contributes to local sustainable development, as it is an activity that generates employment and income, without degrading the environment.

关键词： solar irradiance Renewable Energy Alternative Source of Energy solar

Observation　of　clouds　and　solar　radiation　over　the　Pacific　Ocean　as　relation　to　global　climate

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Acta Oceanologica Sinica 1995年第2期14卷 201-207页

作者： Farn Parungo Clarence Nagamoto Cecilia M. I. R. Girz Jeff Torgerson and Zhou Mingyu (Science and Technology Corporation, Boulder, CO, U. S. A.Air Resources Laboratory, NOAA, Boulder, CO, U. S. A.Forecast Systems Laboratory, NOAA, Boulder, CO, U. S. A.U

During a research cruise over the Pacific Ocean in 1989, solar irradiance was measured with a broad-band pyranometer along the cruise track. Cloud cover was photographed with an all-sky time-lapse came ra. Cloud types were observed and recorded. The data show that both the types and the amounts of clouds affect radiation fluxes on the sea surface. For low-level and middle-level clouds, the correlations (r) between measured irradiance (in Percent of calculated maximum irradiance) and cloud amount (in fraction of sky) were significant: r=-0. 79 and - 0. 66, respectively. For high-level clouds, the correlation was not significant: r=-0. 21. The results indicate that cloud shortwave forcing is a major modifier of the earth's surface insolation and change of cloud amount may affect global climate.

关键词： solar irradiance cloud type cloud cover earth's surface insolation global climate

RADIATIVE CHARACTERISTICS OF AEROSOLS AT GOLMUD ON THE TIBETAN PLATEAU

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Acta meteorologica Sinica 1993年第2期7卷 199-211页

作者：孙治安 Keith P.Shine Department of Meteorology Reading University

The characteristics of atmospheric aerosols in the Golmud desert over the Tibetan (Qinghai-Xizang) Plateau are investigated using the measurements made during the QXPMEX-79.Using spectroscopic observations at the surface and satellite data,the aerosol optical depth is calculated,from which the aerosol size distribution is worked out by means of an inversion method.The effects of vertical distribution of aerosols on irradiance and heating rate profiles are investi- gated using radiation models in conjunction with the assumption of three idealized aerosol profiles.The effect of aerosols on solar irradiance at the surface is also investigated and the results are compared with the observations.It is shown that the solar irradiance can be reduced by up to 100 W m^(-2) in the presence of aerosols,and the heating rate can be increased by 1 Kd^(-1).

关键词： dust aerosol absorption and scattering radiative transfer solar irradiance

Absence of the Impact of the Flux of Cosmic Rays and the Cloud Cover on the Energy Balance of the Earth

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Journal of Atmospheric Science Research 2020年第3期3卷 1-7页

作者： H.I.Abdussamatov Pulkovo Observatory of the RAS St.Petersburg196140Russia

The energy of solar radiation absorbed by the Earth,as well as the thermal radiation of the Earth’s surface,which is released to the space through the atmospheric transparency window,depends on variations of the area of the cloud cover.Svensmark et al.suggest that the increase in the area of the cloud cover in the lower atmosphere,presumably caused by an increase in the flux of galactic cosmic rays during the quasi-bicentennial minimum of solar activity,results only in an increase in the fraction of the solar radiation reflected back to the space and weakens the flux of the solar radiation that reached the Earth surface.It is suggested,without any corresponding calculations of the variations of the average annual energy balance of the EarthЕ,that the consequences will include only a deficit of the solar energy absorbed by the Earth and a cooling of the climate up to the onset of the Little Ice Age.These suggestions ignore simultaneous impact of the opposite aspects of the increase in the area of the cloud cover on the climate warming.The latter will result from a decrease in the power of thermal radiation of the Earth’s surface released to the space,and also in the power of the solar radiation reflected from the Earth’s surface,due to the increase in their absorption and reflection back to the surface.A substantial strengthening in the greenhouse effect and the narrowing of the atmospheric transparency window will also occur.Here,we estimate the impact of all aspects of possible long-term 2%growth of the cloud cover area in the lower atmosphere byЕ.We found that an increase in the cloud cover area in the lower atmosphere will result simultaneously both in the decrease and in the increase in the temperature,which will virtually compensate each other,while the energy balance of the Earth E before and after the increase in the cloud cover area by 2%will stay essentially the same:E1-E0≈0.

关键词： Climate Cosmic rays Cloud Cover Energy Balance Little Ice Age solar irradiance Greenhouse Effect Atmospheric Transparency Window