共查询到20条相似文献，搜索用时 31 毫秒
1.
The Global Ozone Monitoring Experiment (GOME) is the first of a series of European satellite instruments monitoring global ozone and other relevant trace constituents in the UV/visible spectral range. On 20 April 1995, the European Space Agency (ESA) launched the GOME from Kourou, French Guyana, aboard the second European Remote Sensing satellite (ERS-2). In order to obtain the geometric albedo from the backscattered terrestrial radiance measurements, a solar irradiance measurement sequence in the spectral range between 240 nm and 790 nm is carried out once every day. The GOME solar irradiance is recorded at a moderate spectral resolution (0.2–0.4 nm), thus providing an excellent opportunity to contribute to the long-term investigation of solar flux variation associated with the 11-year solar activity cycle from space, which started in 1978 with SBUV (Solar Backscatter UV Experiment) observations on Nimbus-7 and covers solar cycles 21 and 22. This paper briefly describes the GOME spectrometer and measurement mode which are relevant to the solar viewing. Preliminary results from the solar irradiance measurements between 1995 and 1997 and comparisons to SSBUV-8 (Shuttle SBUV) in January 1996 are presented. Solar activity indices used as proxies for solar flux variation are often used to find a correlation with observed variation in atmospheric quantities, for instance, total ozone. Initial results from the GOME Mgii (280 nm) and Caii K (393 nm) solar activity index calculation are presented and discussed. The coupling of solar irradiance variability to global change is a current source of scientific and public concern. This study shows that GOME/ERS-2 (1995–2001) and the next generation of European remote sensing instruments, SCIAMACHY and GOME/METOP, have the potential to provide continuity in the measurements of solar irradiance from space well into the next century. 相似文献
2.
Thuillier G. Hersé M. Labs D. Foujols T. Peetermans W. Gillotay D. Simon P.C. Mandel H. 《Solar physics》2003,214(1):1-22
The SOLar SPECtrum (SOLSPEC) and the SOlar SPectrum (SOSP) spectrometers are two twin instruments built to carry out solar spectral irradiance measurements. They are made of three spectrometers dedicated to observations in the ultraviolet, visible and infrared domains. SOLSPEC flew with the ATmospheric Laboratory for Applications and Science (ATLAS) while SOSP flew on the EUropean Retrieval CArrier (EURECA) missions. ATLAS 1 and 2 data being already published, this paper is mostly dedicated to the ATLAS 3 and EURECA data in the IR domain. Comparisons between the ATLAS data sets and the Upper Atmosphere Research Satellite (UARS) results are made. EURECA IR data are shown and compared with previous results. Our best UV, visible and IR spectra are finally merged into a single absolute solar irradiance spectrum covering the 200 to 2400 nm domain. 相似文献
3.
The study of the minor constituents of the planetary atmospheres from the analysis of the scattered light properties requires
the knowledge of the absolute incident solar irradiance at high resolution. The data were obtained from the UVSP experiment
on board the Solar Maximum Mission satellite in the 184.5–232.5 nm spectral range. We have reconstituted the solar spectrum
measured in three different regions of the solar disk with a spectral resolution of 0.01 nm and a spatial resolution of 3 arc sec.
The wavelength scale was determined with a standard deviation of 0.0025 nm. The comparison of the relative intensities in
three locations of the solar disk with those obtained by other authors allowed us to determine these positions accurately
and to derive the integrated spectrum of the whole disk. Finally, the resulting spectrum has been expressed in absolute units
using the spectral irradiance by the SOLSPEC and SUSIM spectrometers, respectively operated with the ATLAS 1 mission and from
the Upper Atmosphere Research Satellite. We obtained the absolute solar irradiance with an accuracy of 10% in the 184.5–232.5 nm
spectral range with a spectral resolution of 0.01 nm for the first time using data from space observations.
Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1017976515168 相似文献
4.
Thuillier Gérard Hersé Michel Simon Paul C. Labs Dietrich Mandel Holger Gillotay Didier 《Solar physics》1997,171(2):283-302
The SOLSPEC instrument has been built to carry out solar spectral irradiance measurements from space. It consists of three spectrometers designed to measure the solar spectral irradiance from 180 to 3000 nm. It flew for the first time in December 1983 with the SpaceLab 1 mission (SL1) and later with the ATLAS missions after significant improvement of the instrument optics and calibration procedures. For the ATLAS 1 mission in March 1992, the thermal conditions encountered during the measurements were better than those of SL1, leading to better data quality. Furthermore, other Sun spectrometers, two on the same platform and two others on board the Upper Atmosphere Research Satellite, have also carried out UV absolute spectral measurements at the same time. These opportunities allowed comparisons of solar irradiance determinations. The UV part of the measurements made during that mission is presented here as well as its calibration and accuracy analysis. 相似文献
5.
Thomas N. Woods Gary J. Rottman Scott M. Bailey Stanley C. Solomon John R. Worden 《Solar physics》1998,177(1-2):133-146
The solar extreme ultraviolet (EUV) irradiance, the dominant global energy source for Earth's atmosphere above 100 km, is not known accurately enough for many studies of the upper atmosphere. During the absence of direct solar EUV irradiance measurements from satellites, the solar EUV irradiance is often estimated at the 30–50% uncertainty level using both proxies of the solar irradiance and earlier solar EUV irradiance measurements, primarily from the Air Force Geophysics Laboratory (now Phillips Laboratory) rockets and Atmospheric Explorer (AE) instruments. Our sounding rocket measurements during solar cycle 22 include solar EUV irradiances below 120 nm with 0.2 nm spectral resolution, far ultraviolet (FUV) airglow spectra below 160 nm, and solar soft X-ray (XUV) images at 17.5 nm. Compared to the earlier observations, these rocket experiments provide a more accurate absolute measurement of the solar EUV irradiance, because these instruments are calibrated at the National Institute of Standards and Technology (NIST) with a radiometric uncertainty of about 8%. These more accurate sounding-rocket measurements suggest revisions of the previous reference AE–E spectra by as much as a factor of 2 at some wavelengths. Our sounding-rocket flights during the past several years (1988–1994) also provide information about solar EUV variability during solar cycle 22. 相似文献
6.
The Solar–Stellar Irradiance Comparison Experiment {II (SOLSTICE {II), aboard the Solar Radiation and Climate Experiment (SORCE)
spacecraft, consists of a pair of identical scanning grating monochromators, which have the capability to observe both solar
spectral irradiance and stellar spectral irradiance using a single optical system. The SOLSTICE science objectives are to
measure solar spectral irradiance from 115 to 320 nm with a spectral resolution of 1 nm, a cadence of 6 h, and an accuracy
of 5%, to determine its variability with a long-term relative accuracy of 0.5% per year during a 5-year nominal mission, and
to determine the ratio of solar irradiance to that of an ensemble of bright B and A stars to an accuracy of 2%. Those objectives
are met by calibrating instrument radiometric sensitivity before launch using the Synchrotron Ultraviolet Radiation Facility
at the National Institute for Standards and Technology in Gaithersburg, Maryland. During orbital operations irradiance measurements
from an ensemble of bright, stable, main-sequence B and A stars are used to track instrument sensitivity. SORCE was launched
on 25 January 2003. After spacecraft and instrument check out, SOLSTICE {II first observed a series of three stars to establish
an on-orbit performance baseline. Since 6 March 2003, both instruments have been making daily measurements of both the Sun
and stars. This paper describes the pre-flight and in-flight calibration and characterization measurements that are required
to achieve the SOLSTICE science objectives and compares early SOLSTICE{II measurements of both solar and stellar irradiance
with those obtained by SOLSTICE {I on the Upper Atmosphere Research Satellite. 相似文献
7.
T. N. Woods F. G. Eparvier R. Hock A. R. Jones D. Woodraska D. Judge L. Didkovsky J. Lean J. Mariska H. Warren D. McMullin P. Chamberlin G. Berthiaume S. Bailey T. Fuller-Rowell J. Sojka W. K. Tobiska R. Viereck 《Solar physics》2012,275(1-2):115-143
The highly variable solar extreme ultraviolet (EUV) radiation is the major energy input to the Earth’s upper atmosphere, strongly impacting the geospace environment, affecting satellite operations, communications, and navigation. The Extreme ultraviolet Variability Experiment (EVE) onboard the NASA Solar Dynamics Observatory (SDO) will measure the solar EUV irradiance from 0.1 to 105?nm with unprecedented spectral resolution (0.1?nm), temporal cadence (ten seconds), and accuracy (20%). EVE includes several irradiance instruments: The Multiple EUV Grating Spectrographs (MEGS)-A is a grazing-incidence spectrograph that measures the solar EUV irradiance in the 5 to 37?nm range with 0.1-nm resolution, and the MEGS-B is a normal-incidence, dual-pass spectrograph that measures the solar EUV irradiance in the 35 to 105?nm range with 0.1-nm resolution. To provide MEGS in-flight calibration, the EUV SpectroPhotometer (ESP) measures the solar EUV irradiance in broadbands between 0.1 and 39?nm, and a MEGS-Photometer measures the Sun’s bright hydrogen emission at 121.6?nm. The EVE data products include a near real-time space-weather product (Level?0C), which provides the solar EUV irradiance in specific bands and also spectra in 0.1-nm intervals with a cadence of one minute and with a time delay of less than 15?minutes. The EVE higher-level products are Level?2 with the solar EUV irradiance at higher time cadence (0.25?seconds for photometers and ten seconds for spectrographs) and Level?3 with averages of the solar irradiance over a day and over each one-hour period. The EVE team also plans to advance existing models of solar EUV irradiance and to operationally use the EVE measurements in models of Earth’s ionosphere and thermosphere. Improved understanding of the evolution of solar flares and extending the various models to incorporate solar flare events are high priorities for the EVE team. 相似文献
8.
During 1986–1989 at the high-altitude station on the Peak Terskol, Caucasus (h = 3000 m) absolute measurements of the solar disk-centre intensity were performed. The observations were carried out with the specialized solar telescope (D = 23 cm,F = 3 m) and grating spectrometer (F = 2 m, grating 140 × 150 mm, 600 grooves mm–1). The ribbon tungsten lamps used for absolute calibration were calibrated to the USSR standard of spectral intensity and were also compared with the irradiance standard of the PMO/WRC (Davos, Switzerland), with the lamps used in the Alma-Ata Observatory (Kazakhstan) and in Simferopol University for absolute measurements of stellar spectra. Methods and apparatus were improving step by step during 1985–1988. Special care was paid to the study of all possible sources of errors, in particular to the method of correction for atmospheric extinction, to polarization properties of optical elements of the apparatus, and to establishing the most reliable absolute calibration system. Finally, the observations performed during 1989 utilized only the refined methods and apparatus. As a result, the absolute integrals of the solar disk-centre intensity for 1-nm wide spectral bands in the range 310–685 nm are available. We estimate the total error is 2.5% at 310 nm and 2.1% at 680 nm. The absolute irradiance for 5-nm wide spectral bands is also obtained. We compare our results with results by Neckel and Labs (1984), with the irradiance filter measurements performed in PMO/WRC and calibration of the Sun's spectral irradiance to the stellar irradiance standard Vega by Lockwood (1992). Our results show a systematic difference with data by Neckel and Labs in the near-ultraviolet. The results by Neckel and Labs are probably underestimated in this spectral range by 8%.Deceased 20 January 1994. 相似文献
9.
The solar spectral irradiance (SSI) dataset is a key record for studying and understanding the energetics and radiation balance in Earth’s environment. Understanding the long-term variations of the SSI over timescales of the 11-year solar activity cycle and longer is critical for many Sun–Earth research topics. Satellite measurements of the SSI have been made since the 1970s, most of them in the ultraviolet, but recently also in the visible and near-infrared. A limiting factor for the accuracy of previous solar variability results is the uncertainties for the instrument degradation corrections, which need fairly large corrections relative to the amount of solar cycle variability at some wavelengths. The primary objective of this investigation has been to separate out solar cycle variability and any residual uncorrected instrumental trends in the SSI measurements from the Solar Radiation and Climate Experiment (SORCE) mission and the Thermosphere, Mesosphere, Ionosphere, Energetic, and Dynamics (TIMED) mission. A new technique called the Multiple Same-Irradiance-Level (MuSIL) analysis has been developed, which examines an SSI time series at different levels of solar activity to provide long-term trends in an SSI record, and the most common result is a downward trend that most likely stems from uncorrected instrument degradation. This technique has been applied to each wavelength in the SSI records from SORCE (2003?–?present) and TIMED (2002?–?present) to provide new solar cycle variability results between 27 nm and 1600 nm with a resolution of about 1 nm at most wavelengths. This technique, which was validated with the highly accurate total solar irradiance (TSI) record, has an estimated relative uncertainty of about 5% of the measured solar cycle variability. The MuSIL results are further validated with the comparison of the new solar cycle variability results from different solar cycles. 相似文献
10.
The Solar EUV Monitor (SEM) onboard SOHO has measured absolute extreme ultraviolet (EUV) and soft X-ray solar irradiance nearly continuously since January 1996. The EUV Variability Experiment (EVE) on SDO, in operation since April of 2010, measures solar irradiance in a wide spectral range that encompasses the band passes (26?–?34 nm and 0.1?–?50 nm) measured by SOHO/SEM. However, throughout the mission overlap, irradiance values from these two instruments have differed by more than the combined stated uncertainties of the measurements. In an effort to identify the sources of these differences and eliminate them, we investigate in this work the effect of reprocessing the SEM data using a more accurate SEM response function (obtained from synchrotron measurements with a SEM sounding-rocket clone instrument taken after SOHO was already in orbit) and time-dependent, measured solar spectral distributions – i.e., solar reference spectra that were unavailable prior to the launch of the SDO. We find that recalculating the SEM data with these improved parameters reduces mean differences with the EVE measurements from about 20 % to less than 5 % in the 26?–?34 nm band, and from about 35 % to about 15 % for irradiances in the 0.1?–?7 nm band extracted from the SEM 0.1?–?50 nm channel. 相似文献
11.
G. Schmidtke B. Nikutowski C. Jacobi R. Brunner C. Erhardt S. Knecht J. Scherle J. Schlagenhauf 《Solar physics》2014,289(5):1863-1883
SolACES is part of the ESA SOLAR ISS mission that started aboard the shuttle mission STS-122 on 7 February 2008. The instrument has recorded solar extreme ultraviolet (EUV) irradiance from 16 to 150 nm during the extended solar activity minimum and the beginning solar cycle 24 with rising solar activity and increasingly changing spectral composition. The SOLAR mission has been extended from a period of 18 months to >?8 years until the end of 2016. SolACES is operating three grazing incidence planar grating spectrometers and two three-current ionization chambers. The latter ones are considered as primary radiometric detector standards. Re-filling the ionization chambers with three different gases repeatedly and using overlapping band-pass filters, the absolute EUV fluxes are derived in these spectral intervals. This way the serious problem of continuing efficiency changes in space-borne instrumentation is overcome during the mission. Evaluating the three currents of the ionization chambers, the overlapping spectral ranges of the spectrometers and of the filters plus inter-comparing the results from the EUV photon absorption in the gases with different absorption cross sections, there are manifold instrumental possibilities to cross-check the results providing a high degree of reliability to the spectral irradiance derived. During the mission a very strong up-and-down variability of the spectrometric efficiency by orders of magnitude is observed. One of the effects involved is channeltron degradation. However, there are still open questions on other effects contributing to these changes. A survey of the measurements carried out and first results of the solar spectral irradiance (SSI) data are presented. Inter-comparison with EUV data from other space missions shows good agreement such that the international effort has started to elaborate a complete set of EUV-SSI data taking into account all data available from 2008 to 2013. 相似文献
12.
Balloon observations of solar irradiance between 200 and 240 nm have been performed in 1976 and 1977 corresponding to minimum conditions of solar activity. Ultraviolet spectra have been recorded for different zenith angles at an altitude of 41 km by means of a spectrometer with a spectral bandpass of 0.4 nm. Solar irradiances at 1 a.u. confirm previous values obtained by balloon. They are compared with other measurements and discussed in term of possible long-term variability. 相似文献
13.
G. Thuillier G. Schmidtke C. Erhardt B. Nikutowski A. I. Shapiro C. Bolduc J. Lean N. Krivova P. Charbonneau G. Cessateur M. Haberreiter S. Melo V. Delouille B. Mampaey K. L. Yeo W. Schmutz 《Solar physics》2014,289(12):4433-4452
Onboard the International Space Station (ISS), two instruments are observing the solar spectral irradiance (SSI) at wavelengths from 16 to 2900 nm. Although the ISS platform orientation generally precludes pointing at the Sun more than 10?–?14 days per month, in November/December 2012 a continuous period of measurements was obtained by implementing an ISS ‘bridging’ maneuver. This enabled observations to be made of the solar spectral irradiance (SSI) during a complete solar rotation. We present these measurements, which quantify the impact of active regions on SSI, and compare them with data simultaneously gathered from other platforms, and with models of spectral irradiance variability. Our analysis demonstrates that the instruments onboard the ISS have the capability to measure SSI variations consistent with other instruments in space. A comparison among all available SSI measurements during November–December 2012 in absolute units with reconstructions using solar proxies and observed solar activity features is presented and discussed in terms of accuracy. 相似文献
14.
An understanding of solar variability over a broad spectral range and broad range of timescales is needed by scientists studying Earth’s climate. The Total and Spectral Solar Irradiance Sensor (TSIS) Spectral Irradiance Monitor (SIM), is designed to measure solar spectral irradiance (SSI) with unprecedented accuracy from 200 nm to 2400 nm. SIM started daily observations in March 2018. To maintain its accuracy over the course of its anticipated 5-year mission and beyond, TSIS SIM needs to be corrected for optical degradation, common for solar viewing instruments. The differing long-term trends of various independent solar-irradiance records attest to the challenge at hand.
The correction of TSIS SIM for optical degradation is based on piecewise linear fits that bring the three instrument channels into agreement. It is fundamentally different to the correction applied to the TSIS SIM predecessor on SORCE. The correction facilitates reproducibility, uncertainty estimation and is measurement-based. Corrected, integrated TSIS SIM SSI agrees with independent observations of total solar irradiance to within 45 ppm as well as various solar-irradiance models. TSIS SIM SSI is available at: http://lasp.colorado.edu/lisird/.
相似文献15.
G. Thuillier T. Foujols D. Bolsée D. Gillotay M. Hersé W. Peetermans W. Decuyper H. Mandel P. Sperfeld S. Pape D. R. Taubert J. Hartmann 《Solar physics》2009,257(1):185-213
SOLAR is a set of three solar instruments measuring the total and spectral absolute irradiance from 16 nm to 3080 nm for solar,
atmospheric and climatology physics. It is an external payload for the COLUMBUS laboratory launched on 7 February 2008. The
mission’s primary objective is the measurement of the solar irradiance with the highest possible accuracy, and its variability
using the following instruments: SOL-ACES (SOLar Auto-Calibrating EUV/UV Spectrophotometers) consists of four grazing incidence
planar gratings measuring from 16 nm to 220 nm; SOLSPEC (SOLar SPECtrum) consists of three double gratings spectrometers,
covering the range 165 nm to 3080 nm; and SOVIM (SOlar Variability Irradiance Monitor) is combining two types of absolute
radiometers and three-channel filter – radiometers. SOLSPEC and SOL-ACES have been calibrated by primary standard radiation
sources of the Physikalisch-Technische Bundesanstalt (PTB). Below we describe SOLSPEC, and its performance. 相似文献
16.
G. Thuillier M. DeLand A. Shapiro W. Schmutz D. Bolsée S. M. L. Melo 《Solar physics》2012,277(2):245-266
We present a new method to reconstruct the solar spectrum irradiance in the Ly α – 400 nm region, and its variability, based on the Mg ii index and neutron-monitor measurements. Measurements of the solar spectral irradiance available in the literature have been
made with different instruments at different times and different spectral ranges. However, climate studies require harmonised
data sets. This new approach has the advantage of being independent of the absolute calibration and aging of the instruments.
First, the Mg ii index is derived using solar spectra from Ly α (121 nm) to 410 nm measured from 1978 to 2010 by several space missions. The variability of the spectra with respect to a
chosen reference spectrum as a function of time and wavelength is scaled to the derived Mg ii index. The set of coefficients expressing the spectral variability can be applied to the chosen reference spectrum to reconstruct
the solar spectra within a given time frame or Mg ii index values. The accuracy of this method is estimated using two approaches: direct comparison with particular cases where
solar spectra are available from independent measurements, and calculating the standard deviation between the measured spectra
and their reconstruction. From direct comparisons with measurements we obtain an accuracy of about 1 to 2%, which degrades
towards Ly α. In a further step, we extend our solar spectral-irradiance reconstruction back to the Maunder Minimum introducing the relationship
between the Mg ii index and the neutron-monitor data. Consistent measurements of the Mg ii index are not available prior to 1978. However, we remark that over the last three solar cycles, the Mg ii index shows strong correlation with the modulation potential determined from the neutron-monitor data. Assuming that this
correlation can be applied to the past, we reconstruct the Mg ii index from the modulation potential back to the Maunder Minimum, and obtain the corresponding solar spectral-irradiance reconstruction
back to that period. As there is no direct measurement of the spectral irradiance for this period we discuss this methodology
in light of the other proposed approaches available in the literature. The use of the cosmogenic-isotope data provides a major
advantage: it provides information about solar activity over several thousands years. Using technology of today, we can calibrate
the solar irradiance against activity and thus reconstruct it for the times when cosmogenic-isotope data are available. This
calibration can be re-assessed at any time, if necessary. 相似文献
17.
Thomas N. Woods Phillip C. Chamberlin W. K. Peterson R. R. Meier Phil G. Richards Douglas J. Strickland Gang Lu Liying Qian Stanley C. Solomon B. A. Iijima A. J. Mannucci B. T. Tsurutani 《Solar physics》2008,250(2):235-267
Solar soft X-ray (XUV) radiation is highly variable on all time scales and strongly affects Earth’s ionosphere and upper atmosphere;
consequently, the solar XUV irradiance is important for atmospheric studies and for space weather applications. Although there
have been several recent measurements of the solar XUV irradiance, detailed understanding of the solar XUV irradiance, especially
its variability during flares, has been hampered by the broad bands measured in the XUV range. In particular, the simple conversion
of the XUV photometer signal into irradiance, in which a static solar spectrum is assumed, overestimates the flare variations
by more than a factor of two as compared to the atmospheric response to the flares. To address this deficiency in the simple
conversion, an improved algorithm using CHIANTI spectral models has been developed to process the XUV Photometer System (XPS)
measurements with its broadband photometers. Model spectra representative of quiet Sun, active region, and flares are combined
to match the signals from the XPS and produce spectra from 0.1 to 40 nm in 0.1-nm intervals for the XPS Level 4 data product.
The two XPS instruments are aboard NASA’s Solar Radiation and Climate Experiment (SORCE) and Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics (TIMED) satellites. In addition, the XPS responsivities have been updated for the latest XPS data processing version. The
new XPS results are consistent with daily variations from the previous simple conversion technique used for XPS and are also
consistent with spectral measurements made at wavelengths longer than 27 nm. Most importantly, the XPS flare variations are
reduced by factors of 2 – 4 at wavelengths shorter than 14 nm and are more consistent, for the first time, with atmospheric
response to solar flares. Along with the details of the new XPS algorithm, several comparisons to dayglow and photoelectron
measurements and model results are also presented to help verify the accuracy of the new XUV irradiance spectra. 相似文献
18.
Paul C. Simon 《Solar physics》1981,74(1):273-291
The solar ultraviolet irradiance measurements in the 120–400 nm wavelength range are reviewed and compared showing still important discrepancies between the irradiance values deduced from the most recent observations.The possible variations of the solar ultraviolet irradiances with the 27-day rotation period of the Sun and with the 11-year activity cycle are presented and discussed on the basis of the available irradiation fluxes obtained during the rising phase of solar cycle 21.The spectral features of both kinds of variation are clearly related to the solar atmospheric layer from which the corresponding radiation is emitted.Proceedings of the 14th ESLAB Symposium on Physics of Solar Variations, 16–19 September 1980, Scheveningen, The Netherlands. 相似文献
19.
M. Meftah L. Damé D. Bolsée N. Pereira D. Sluse G. Cessateur A. Irbah A. Sarkissian D. Djafer A. Hauchecorne S. Bekki 《Solar physics》2017,292(8):101
The solar spectrum is a key parameter for different scientific disciplines such as solar physics, climate research, and atmospheric physics. The SOLar SPECtrometer (SOLSPEC) instrument of the Solar Monitoring Observatory (SOLAR) payload onboard the International Space Station (ISS) has been built to measure the solar spectral irradiance (SSI) from 165 to 3088 nm with high accuracy. To cover the full wavelength range, three double-monochromators with concave gratings are used. We present here a thorough analysis of the data from the third channel/double-monochromator, which covers the spectral range between 656 and 3088 nm. A new reference solar spectrum is therefore obtained in this mainly infrared wavelength range (656 to 3088 nm); it uses an absolute preflight calibration performed with the blackbody of the Physikalisch-Technische Bundesanstalt (PTB). An improved correction of temperature effects is also applied to the measurements using in-flight housekeeping temperature data of the instrument. The new solar spectrum (SOLAR–IR) is in good agreement with the ATmospheric Laboratory for Applications and Science (ATLAS?3) reference solar spectrum from 656 nm to about 1600 nm. However, above 1600 nm, it agrees better with solar reconstruction models than with spacecraft measurements. The new SOLAR/SOLSPEC measurement of solar spectral irradiance at about 1600 nm, corresponding to the minimum opacity of the solar photosphere, is 248.08 ± 4.98 mW?m?2?nm?1 (1?\(\sigma\)), which is higher than recent ground-based evaluations. 相似文献
20.
太阳总辐照是指在地球大气层顶接收到的太阳总辐射照度,也叫"太阳常数",但它实际上并非常数。太阳总辐照随波长的分布即为太阳分光辐照。太阳辐照变化的研究,对理解太阳表面及内部活动的物理过程、机制,研究地球大气、日地关系,解决人类面临的全球气候变暖的挑战等,都具有重要意义。首先简单介绍了太阳辐照,回顾了太阳辐照的空间观测;接着介绍了观测数据的并合,以及对合成数据的一些研究;然后讨论了太阳辐照变化的原因,简述了太阳总辐照的重构及其在气候研究上的一些应用,并进行必要的评论;最后对未来的研究方向提出了一些看法。 相似文献