Solar Spectral Irradiance Variability in November/December 2012: Comparison of Observations by Instruments on the International Space Station and Models

Thuillier, G.; Schmidtke, G.; Erhardt, Christian; Nikutowski, B.; Шапиро, А. И.; Bolduc, Chantal; Lean, J.; Krivova, N. A.; Charbonneau, Paul; Cessateur, Gaël; Haberreiter, M.; Melo, S. M. L.; Delouille, Véronique; Mampaey, Benjamin; Yeo, Kok Leng; Schmutz, W.

doi:10.1007/s11207-014-0588-5

Cited by 11 publications

(7 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In particular, we describe the update of COSI ALI-scheme. The acronym COSI has been used both for the NLTE radiative transfer code (see Haberreiter et al 2008;and Shapiro et al 2010, further referenced here as S2010) as well as to model solar irradiance variability (Shapiro et al 2011;Thuillier et al 2014b). Spectral synthesis and irradiance variability modeling are two adjacent, but separate problems.…”

Section: Introductionmentioning

confidence: 99%

“…Consequently, the main application of NESSY has been calculating the spectra of the quiet Sun and magnetic features for the physics-based modeling of solar irradiance variability. The code has been used in several reconstructions of the historic solar irradiance (Shapiro et al 2011;Thuillier et al 2012) as well as for modeling of the solar irradiance during the satellite era Thuillier et al 2014b). Recently, Shapiro et al (2015) incorporated NESSY calculations into the SATIRE model (Spectral And Total Irradiance REconstruction, see Fligge et al 2000;Krivova et al 2003) of solar irradiance variability.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

NESSY: NLTE spectral synthesis code for solar and stellar atmospheres

Tagirov

Шапиро

Schmutz

2017

A&A

Self Cite

View full text Add to dashboard Cite

Context. Physics-based models of solar and stellar magnetically-driven variability are based on the calculation of synthetic spectra for various surface magnetic features as well as quiet regions, which are a function of their position on the solar or stellar disc. Such calculations are performed with radiative transfer codes tailored for modeling broad spectral intervals. Aims. We aim to present the NLTE Spectral SYnthesis code (NESSY), which can be used for modeling of the entire (UV-visible-IR and radio) spectra of solar and stellar magnetic features and quiet regions. Methods. NESSY is a further development of the COde for Solar Irradiance (COSI), in which we have implemented an accelerated Λ-iteration (ALI) scheme for co-moving frame (CMF) line radiation transfer based on a new estimate of the local approximate Λ-operator. Results. We show that the new version of the code performs substantially faster than the previous one and yields a reliable calculation of the entire solar spectrum. This calculation is in a good agreement with the available observations.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

NESSY: NLTE spectral synthesis code for solar and stellar atmospheres

Tagirov

Шапиро

Schmutz

2017

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition, the SOLSPEC instrument (Thuillier et al 2009) aboard the International Space Station (ISS) has been conducting irradiance measurements from 200 nm to 2400 nm since 2008. However, the SOLSPEC data have so far mainly been used to study the 27-day solar modulation during specific observation campaigns as described by Thuillier et al (2014).…”

Section: Introductionmentioning

confidence: 99%

Solar irradiance observations with PREMOS filter radiometers on the PICARD mission: In-flight performance and data release

Cessateur

Schmutz

Wehrli

et al. 2016

A&A

Self Cite

View full text Add to dashboard Cite

Context. The PREcision Monitoring Sensor (PREMOS) is a solar radiometer on board the French PICARD mission that was launched in June 2010 and decommissioned in April 2014. Aims. The PREMOS radiometer obtains solar irradiance measurements in specific spectral windows in the UV, visible, and nearinfrared. In this paper, the PREMOS data and calibration methods are presented. Methods. Using back-up channels, the degradation can theoretically be assessed to correct operational channels. However, a strong degradation within all PREMOS channels requires the application of additional methods, namely using back-up channels and assessing the degradation via a proxy-based model. Results. The corrected Level 3 PREMOS data are then used in different contexts in order to be validated. First, the signature of the p-mode are retrieved from the PREMOS data. The Venus transit allows us to empirically determine the intrinsic noise level within the PREMOS high cadence data for the visible and near-infrared channels. We then compare the PREMOS data directly to other data sets, namely from the SOLar-STellar Irradiance Comparison Experiment (SOLSTICE) and the Solar Irradiance Monitor (SIM) instruments on board the SOlar Radiation and Climate Experiment (SORCE) spacecraft. Regarding the UV channels, we found an excellent correlation over the lifetime of the PREMOS mission. The ratio between SORCE and PREMOS observations is always less than 1%. Regarding the SSI measurements in the visible and near-infrared, a comparison of short-term variations (i.e. 27-day modulation) shows a rather good correlation by taking into consideration the intrinsic noise within both SIM and PREMOS observations.

show abstract

“…It is thus vexing that the magnitude of the variability in this range differs by a factor of several among the different models and the measurements (Krivova et al 2006;Harder et al 2009;Unruh et al 2012;Yeo et al 2015Yeo et al , 2017a. Empirical models tend to return variability amplitudes that are almost a factor of two lower than semiempirical models suggest (Thuillier et al 2014;Yeo et al 2014Yeo et al , 2015Yeo et al , 2017aEgorova et al 2018), while the insufficient stability of most instruments (Yeo et al 2015) compared to the solar cycle variability above 250 nm -400 nm does not allow deciding between these different amplitudes.…”

Section: Introductionmentioning

confidence: 99%

Readdressing the UV solar variability with SATIRE-S: non-LTE effects

Tagirov

Шапиро

Krivova

et al. 2019

A&A

Self Cite

View full text Add to dashboard Cite

Context. Solar spectral irradiance (SSI) variability is one of the key inputs to models of the Earth's climate. Understanding solar irradiance fluctuations also helps to place the Sun among other stars in terms of their brightness variability patterns and to set detectability limits for terrestrial exo-planets. Aims. One of the most successful and widely used models of solar irradiance variability is SATIRE-S. It uses spectra of the magnetic features and surrounding quiet Sun computed with the ATLAS9 spectral synthesis code under the assumption of Local Thermodynamic Equilibrium (LTE). SATIRE-S has been at the forefront of solar variability modelling, but due to the limitations of the LTE approximation its output SSI has to be empirically corrected below 300 nm, which reduces the physical consistency of its results. This shortcoming is addressed in the present paper. Methods. We replace the ATLAS9 spectra of all atmospheric components in SATIRE-S with the spectra calculated using the non-LTE Spectral Synthesis Code (NESSY). We also use Fontenla et al. (1999) temperature and density stratification models of the solar atmosphere to compute the spectrum of the quiet Sun and faculae. Results. We compute non-LTE contrasts of spots and faculae and combine them with the SDO/HMI filling factors of the active regions to calculate the total and spectral solar irradiance variability during solar cycle 24. Conclusions. The non-LTE contrasts result in total and spectral solar irradiance in good agreement with the empirically corrected output of the LTE version. This suggests that empirical correction introduced into SATIRE-S output is well judged and that the corrected total and spectral solar irradiance obtained from the SATIRE-S model in LTE is fully consistent with the results of non-LTE computations.

show abstract

Solar Spectral Irradiance Variability in November/December 2012: Comparison of Observations by Instruments on the International Space Station and Models

Cited by 11 publications

References 43 publications

NESSY: NLTE spectral synthesis code for solar and stellar atmospheres

NESSY: NLTE spectral synthesis code for solar and stellar atmospheres

Solar irradiance observations with PREMOS filter radiometers on the PICARD mission: In-flight performance and data release

Readdressing the UV solar variability with SATIRE-S: non-LTE effects

Contact Info

Product

Resources

About