Total Solar Irradiance Trend During Solar Cycles 21 and 22

Science ◽  
1997 ◽  
Vol 277 (5334) ◽  
pp. 1963-1965 ◽  
Author(s):  
Richard C. Willson
Keyword(s):  
Solar Irradiance ◽  
Total Solar Irradiance ◽  
Solar Cycles

Solar Irradiance: Instrument-Based Advances

2018 ◽  
Vol 14 (A30) ◽  
pp. 354-357
Author(s):  
Greg Kopp
Keyword(s):  
Solar Cycle ◽  
Solar Flares ◽  
Solar Irradiance ◽  
Large Scale ◽  
Total Solar Irradiance ◽  
Climate Forcing ◽  
Solar Cycles ◽  
Climate Stability ◽  
Measurement Results ◽  
Measuring Space

AbstractVariations of the total solar irradiance (TSI) over long periods of time provide natural Earth-climate forcing and are thus important to monitor. Variations over a solar cycle are at the 0.1 % level. Variations on multi-decadal to century timescales are (fortunately for our climate stability) very small, which drives the need for highly-accurate and stable measurements over correspondingly long periods of time to discern any such irradiance changes. Advances to TSI-measuring space-borne instruments are approaching the desired climate-driven measurement accuracies and on-orbit stabilities. I present a summary of the modern-instrument improvements enabling these measurements and present some of the solar-variability measurement results from recent space-borne instruments, including TSI variations on timescales from solar flares and large-scale convection to solar cycles.

Extending the TSIS-1 Hybrid Solar Reference Spectrum (HSRS) to Span 0.202 to 200 um

2021 ◽  
Author(s):  
Odele Coddington ◽  
Erik Richard ◽  
Dave Harber ◽  
Peter Pilewskie ◽  
Tom Woods ◽  
...  
Keyword(s):  
Spectral Resolution ◽  
Solar Irradiance ◽  
Solar Spectrum ◽  
Total Solar Irradiance ◽  
Spectral Irradiance ◽  
High Spectral Resolution ◽  
Reference Spectrum ◽  
Solar Cycles ◽  
Theoretical Understanding ◽  
High Resolution Data

<p>Recently, we incorporated our new understanding of the absolute scale of the solar spectrum as measured by the Spectral Irradiance Monitor (SIM) on the Total and Spectral Solar Irradiance Sensor (TSIS-1) mission and the Compact SIM (CSIM) flight demonstration into a solar irradiance reference spectrum representing solar minimum conditions between solar cycles 24 and 25. This new reference spectrum, called the TSIS-1 Hybrid Solar Reference Spectrum (HSRS), is developed by re-normalizing independent, very high spectral resolution datasets to the TSIS-1 SIM absolute irradiance scale. The high-resolution data are from the Airforce Geophysical Laboratory (AFGL), the Quality Assurance of Ultraviolet Measurements In Europe (QASUME) campaign, the Kitt Peak National Observatory (KPNO) and the Jet Propulsion Laboratory’s (JPL) Solar Pseudo-Transmittance Spectrum (SPTS). The TSIS-1 HSRS spans 0.202 µm to 2.73 µm and has a spectral resolution of 0.01 nm or better. Uncertainties are 0.3% between 0.4 and 2.365 mm and 1.3% at wavelengths outside that range</p><p>Recently, we have extended the long wavelength limit of the TSIS-1 HSRS from 2.73 µm to 200 µm with JPL SPTS solar line data through ~ 16 µm and theoretical understanding as represented in a computed solar irradiance spectrum by R. Kurucz. The extension expands the utility of this new solar irradiance reference spectrum to include Earth energy budget studies because it encompasses an integrated energy in excess of 99.99% of the total solar irradiance.</p><p>In this work, we discuss the TSIS-1 HSRS, the extension and uncertainties, and demonstrate consistency with TSIS-1 SIM and CSIM solar spectral irradiance observations and TSIS-1 Total Irradiance Monitor (TIM) total solar irradiance observations. Additionally, we compare the TSIS-1 HSRS against independent measured and modeled solar reference spectra.</p>

scholarly journals Solar Monitoring has a Past and Present: Does it have a Future?

1994 ◽  
Vol 143 ◽  
pp. 4-10 ◽  
Author(s):  
Richard C. Willson
Keyword(s):  
United States ◽  
Solar Irradiance ◽  
The United States ◽  
Total Solar Irradiance ◽  
Collaborative Effort ◽  
Solar Cycles ◽  
Earth Observing System ◽  
Total Irradiance ◽  
Sustained Effort

Intrinsic variations of total solar irradiance have, after nearly a century of sustained effort, been demonstrated by flight experiments during solar cycles 21 and 22. This accomplishment has been the result of a collaborative effort on behalf of several groups of researchers in both the United States and Europe. The overriding concern at this point of time is whether the integrity of the precision long-term solar total irradiance database, which began at the maximum of solar cycle 21 and continues in the present, will be lost in the late 1990’s, prior to the inception of experiments planned for the NASA Earth Observing System beginning in 2002. Experiments are not currently in place to prevent an unbridgeable discontinuity in the precision total solar irradiance database.

Comparison of Total Solar Irradiance with NASA/National Solar Observatory Spectromagnetograph Data in Solar Cycles 22 and 23

2003 ◽  
Vol 589 (1) ◽  
pp. 658-664 ◽  
Author(s):  
Harrison P. Jones ◽  
Detrick D. Branston ◽  
Patricia B. Jones ◽  
Miruna D. Popescu
Keyword(s):  
Solar Irradiance ◽  
Total Solar Irradiance ◽  
Solar Observatory ◽  
Solar Cycles ◽  
National Solar Observatory

scholarly journals Modelling solar irradiance from ground-based photometric observations

2020 ◽  
Vol 10 ◽  
pp. 45 ◽  
Author(s):  
Theodosios Chatzistergos ◽  
Ilaria Ermolli ◽  
Fabrizio Giorgi ◽  
Natalie A. Krivova ◽  
Cosmin Constantin Puiu
Keyword(s):  
Solar Cycle ◽  
Solar Irradiance ◽  
Total Solar Irradiance ◽  
Visible Range ◽  
Solar Cycles ◽  
Term Trend ◽  
Photometric Observations ◽  
San Fernando ◽  
Long Term Trend

Total solar irradiance (TSI) has been monitored from space since 1978, i.e. for about four solar cycles. The measurements show a prominent variability in phase with the solar cycle, as well as fluctuations on timescales shorter than a few days. However, the measurements were done by multiple and usually relatively short-lived missions. The different absolute calibrations of the individual instruments and the unaccounted for instrumental trends make estimates of the possible long-term trend in the TSI highly uncertain. Furthermore, both the variability and the uncertainty are strongly wavelength-dependent. While the variability in the UV irradiance is clearly in-phase with the solar cycle, the phase of the variability in the visible range has been debated. In this paper, we aim at getting an insight into the long-term trend of TSI since 1996 and the phase of the solar irradiance variations in the visible part of the spectrum. We use independent ground-based full-disc photometric observations in Ca II K and continuum from the Rome and San Fernando observatories to compute the TSI since 1996. We follow the empirical San Fernando approach based on the photometric sum index. We find a weak declining trend in the TSI of $ {-7.8}_{-0.8}^{+4.9}\times 1{0}^{-3}$ Wm−2 y−1 between the 1996 and 2008 activity minima, while between 2008 and 2019 the reconstructed TSI shows no trend to a marginally decreasing (but statistically insignificant) trend of $ {-0.1}_{-0.02}^{+0.25}\times 1{0}^{-3}$ Wm−2 y−1. The reference TSI series used for the reconstruction does not significantly affect the determined trend. The variation in the blue continuum (409.2 nm) is rather flat, while the variation in the red continuum (607.1 nm) is marginally in anti-phase, although this result is extremely sensitive to the accurate assessment of the quiet Sun level in the images. These results provide further insights into the long-term variation of the TSI. The amplitude of the variations in the visible is below the uncertainties of the processing, which prevents an assessment of the phase of the variations.

scholarly journals Statistical analysis of Sunspot and total solar irradiance effects on the climate in kirkuk area for three solar cycles (22,23,24)

2019 ◽  
Vol 24 (5) ◽  
pp. 70
Author(s):  
Heba Abdulla Attya1 ◽  
Wafaa H. A. Zaki1 ◽  
Omer sabah ibrahiem Al-Tamimi2
Keyword(s):  
Statistical Analysis ◽  
Correlation Coefficient ◽  
Air Temperature ◽  
Solar Irradiance ◽  
Sunshine Duration ◽  
Total Solar Irradiance ◽  
Radiation Budget ◽  
Annual Rainfall ◽  
Solar Cycles ◽  
The Impact

In this study Sunspot number(SSN) and Total solar irradiance(TSI w ) observation were extracted from the Solar Influences Data analysis Center (SIDC) and Earth Radiation Budget Satellite (ERBS) for solar cycles 22,23 and 24 (1988-2017) and for the same cycles the parameters of climate were taken from the meteorological data recorded in Kirkuk station, which includes annual relative humidity(RH%),annual air temperature (cº)(T), annual Rainfall (mm)(p), and annual Sunshine duration(h/day)(SH).The  statistical correlation between the adopted solar and climate parameters has been achieved by using Statistical program (SPSS) version (23). From this statistical analysis shows that there is a correlation between SH with both (SSN) and (TSI) less than 0.5  that is mean (SSN)  and (TSI) have little effect on SH while the correlation is weak or missing between both (SSN) and solar (TSI) with RH% through the correlation coefficient values (0.05,0.032). The effect of (TSI) on the air temperature  more than the impact of (SSN) but  less than 0.5. The effect of (SSN) more than (TSI) on the amount of rainfall less than 0.5 according to the correlation coefficient value .this investigation shows that the climate in Kirkuk is clearly influenced by solar activity which includes SSN and TSI.   http://dx.doi.org/10.25130/tjps.24.2019.092

scholarly journals Comparison of Decadal Trends among Total Solar Irradiance Composites of Satellite Observations

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Nicola Scafetta ◽  
Richard C. Willson
Keyword(s):  
Solar Irradiance ◽  
Total Solar Irradiance ◽  
Satellite Observations ◽  
Radiation Budget ◽  
Solar Cycles ◽  
Upward Trend ◽  
Increasing Trend ◽  
Decadal Trend ◽  
Primary Focus ◽  
Sensor Degradation

We present a new analysis of the two-decade-old controversy over interpretation of satellite observations of total solar irradiance (TSI) since 1978 and the implications of our findings for TSI as a driver of climate change. Our approach compares the methods of constructing the two most commonly referenced TSI composites (ACRIM and PMOD) that relate successive observational databases and two others recently constructed using a novel statistical approach. Our primary focus is on the disparate decadal trending results of the ACRIM and PMOD TSI composite time series, namely, whether they indicate an increasing trend from 1980 to 2000 and a decreasing trend thereafter (ACRIM) or a continuously decreasing trend since 1980 (PMOD). Construction of the four-decade observational TSI composites from 1978 to the present requires the use of results from two less precise Earth Radiation Budget experiments (Nimbus7/ERB and ERBS/ERBE) during the so-called ACRIM-Gap (1989.5–1991.8), between the end of the ACRIM1 and the beginning of the ACRIM2 experiments. The ACRIM and PMOD composites used the ERB and ERBE results, respectively, to bridge the gap. The well-established paradigm of positive correlation between Solar Magnetic Field Strength (SMFS) and TSI supports the validity of the upward trend in the ERB results and the corresponding decadal upward trend of the ACRIM composite during solar cycles 21 and 22. The ERBE results have a sensor degradation caused downward gap trend, contrary to the SMFS/TSI paradigm, that biased the PMOD composite decadal trend downward during solar cycles 21 and 22. The different choice of gap bridging data is clearly the cause of the ACRIM and PMOD TSI trending difference, agreeing closely in both magnitude and direction. We also analyze two recently proposed statistical TSI composites. Unfortunately their methodology cannot account for the gap degradation of the ERBE experiment and their resulting uncertainties are too large to uniquely distinguish between the trending of the ACRIM and PMOD composites. Our analysis supports the ACRIM TSI increasing trend during the 1980 to 2000 period, followed by a long-term decreasing trend since.

scholarly journals Secular total solar irradiance trend during solar cycles 21-23

2003 ◽  
Vol 30 (5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Richard C. Willson ◽  
Alexander V. Mordvinov
Keyword(s):  
Solar Irradiance ◽  
Total Solar Irradiance ◽  
Solar Cycles

scholarly journals Preliminary Design of the Brazilian's National Institute for Space Research Broadband Radiometer for Solar Observations

2016 ◽  
Vol 12 (S328) ◽  
pp. 224-226
Author(s):  
L. A. Berni ◽  
L. E. A. Vieira ◽  
G.S. Savonov ◽  
A. Dal Lago ◽  
O. Mendes ◽  
...  
Keyword(s):  
Solar Irradiance ◽  
Total Solar Irradiance ◽  
Space Research ◽  
Preliminary Design ◽  
The Sun ◽  
Total Radiation ◽  
Solar Cycles ◽  
Long Term Stability ◽  
Solar Observations

AbstractThe Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).

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