Flare Irradiance Spectral Model (FISM)

LISIRD - FISM Averages
FISM daily average data for the integrated 0.1-193 nm VUV band over 6 solar cycles from 1947-Present
LISIRD - FISM Flare
FISM 1-minute resolution data for the 154.5 nm bin during the X17 flare on October 28, 2003

Dataset: Select by date: to (YYYY-DOY)
Entire dataset as IDL .sav file

The Flare Irradiance Spectral Model (FISM) is an empirical model of the solar irradiance spectrum from 0.1 to 190 nm at 1 nm resolution and on a 1-minute time cadence. This model is based on the data provided by the Solar Extreme ultraviolet Experiment (SEE) on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite and the Solar Stellar Irradiance Comparison Experiment (SOLSTICE) on the Upper Atmospheric Research Satellite (UARS). The goal of FISM is to provide accurate solar spectral irradiances over the vacuum ultraviolet range (VUV) as input for ionospheric and thermospheric models used for space weather research and operations. The FISM accounts for the significant irradiance changes due to solar flares, which includes orders of magnitude increases in the X-rays to factors of two increases in the extreme ultraviolet wavelengths (EUV: 10-120 nm), as well as the solar cycle and solar rotational variations. The FISM is shown to model the solar cycle and solar rotational variations to within 7% in the VUV wavelengths as well as describe the changes in irradiance due to solar flares to within 15% at most VUV wavelengths. The FISM therefore provides the most accurately available values of the VUV irradiance at this high of temporal resolution and with 100% coverage at this resolution from 1986 to the present.

Contact Information:

Phillip Chamberlin
Phillip.C.Chamberlin@nasa.gov
Solar Physics Laboratory, Code 671
Greenbelt, MD 20771
(301)286-6806 (work)

File type:

IDL saveset

File name format:

FISM_TR_YYYYDDD_v00_01.sav (*_00.sav used TIMED SEE version 8 data)
TR: Temporal Resolution
Default Flare data: '60sec' (e.g. fism_60sec_2003301_v00_01.sav)
Default Daily data: 'daily' (e.g. fism_daily_v00_01.sav)
YYYY: Year of data set, eg 1960
DDD: Day of Year of data set, eg 001 is Jan 1 and 365 is Dec 31

Arrays [and length] from the restored saveset for FLARE data sets:

date [1]: YYYYDDD
Year and Day of Year

utc [*]: the UTC seconds of day for Year Day of Year given in 'date'
* dimension will have a length of 1440 for the 60-sec temp. res. data

FISM_pred [*, 195]: The FISM predicted spectrum in W/m^2/nm
* corresponds to the seconds of day array, 'utc'; 195 elements correspond to the wavelength array, 'fism_wv'

FISM_wv [195]: The FISM wavelength array, in nm
these are 1-nm bins, given at the center of the bin (eg 1.5 is the 1-nm bin centered at 1.5 nm ranging from 1.0 nm to 1.99 nm)

FISM_error [195]: The 1-sigma percent error as a function of wavelength
multiply this array by the corresponding spectrum, FISM_pred[i,195], to get the absolute 1-sigma error value.

Optional arrays that may be included in the FLARE saveset:

grad_flare [*,195]: the FISM estimated gradual phase flare contribution only (no daily value or impulsive phase contributions), in W/m^2/nm

imp_flare [*,195]: the FISM estimated impulsive phase flare contribution only (no daily value or gradual phase contributions), in W/m^2/nm

Arrays [and length] from the restored saveset for DAILY median data sets:

day_ar [1]: YYYYDDD
Year and Day of Year

utc [1]: 0

FISM_pred [195]: The FISM predicted daily median spectrum in W/m^2/nm
195 elements correspond to the wavelength array, 'fism_wv'

FISM_wv [195]: The FISM wavelength array, in nm
these are 1-nm bins, given at the center of the bin (eg 1.5 is the 1-nm bin centered at 1.5 nm ranging from 1.0 nm to 1.99 nm)

FISM_error [195]: The 1-sigma percent error as a function of wavelength
multiply this array by the corresponding spectrum, FISM_pred[195], to get the absolute 1-sigma error value.
This represents FISM's ability to reproduces the base data set (e.g. TIMED SEE)

FISM_abs_error[195]: The FISM standard deviation ('FISM_error') multiplied in quadrature with the uncertainties of the base data set (e.g. TIMED SEE) that gives the total FISM uncertainty.

Chamberlin, P. C., T. N. Woods, and F. G. Eparvier, Flare Irradiance Spectral Model (FISM): Flare component algorithms and results, Space Weather, 6, S05001, doi:10.1029/2007SW000372, 2008.

Chamberlin, P. C., T. N. Woods, and F. G. Eparvier, Flare Irradiance Spectral Model (FISM): Daily component algorithms and results, Space Weather, 5, S07005, doi:10.1029/2007SW000316, 2007.

Peterson, W. K., T. N. Woods, P. C. Chamberlin, and P. G. Richards, Photoelectron flux variations observed from the FAST satellite, Adv. Space Res., doi:10.1016/j.asar.2007.08.038, 2007.

Woods, T. N., G. Kopp, and P. C. Chamberlin, Contributions of the Solar Ultraviolet Irradiance to the Total Solar Irradiance During Large Flares, J. Geophys. Res., 111, A10S14, doi: 10.1029/2005JA011507, 2006.

Qian, Liying; Burns, Alan G.; Chamberlin, Phillip C.; Solomon, Stanley C. Flare location on the solar disk: Modeling the thermosphere and ionosphere response.

Woods, T. N.; Eparvier, F. G.; Hock, R.; Jones, A. R.; Woodraska, D.; Judge, D.; Didkovsky, L.; Lean, J.; Mariska, J.; Warren, H.; and 8 coauthors. Extreme Ultraviolet Variability Experiment (EVE) on the Solar Dynamics Observatory (SDO): Overview of Science Objectives, Instrument Design, Data Products, and Model Developments.

Peterson, W. K.; Stavros, E. N.; Richards, P. G.; Chamberlin, P. C.; Woods, T. N.; Bailey, S. M.; Solomon, S. C. Photoelectrons as a tool to evaluate spectral variations in solar EUV irradiance over solar cycle timescales.

Smithtro, C. G.; Solomon, S. C. An improved parameterization of thermal electron heating by photoelectrons, with application to an X17 flare.

Peterson, W. K.; Chamberlin, P. C.; Woods, T. N.; Richards, P. G. Temporal and spectral variations of the photoelectron flux and solar irradiance during an X class solar flare.

Evans, J. S.; Strickland, D. J.; Woo, W. K.; McMullin, D. R.; Plunkett, S. P.; Viereck, R. A.; Hill, S. M.; Woods, T. N.; Eparvier, F. G. Early Observations by the GOES-13 Solar Extreme Ultraviolet Sensor (EUVS).

Woods, Thomas N.; Chamberlin, Phillip C. Comparison of solar soft X-ray irradiance from broadband photometers to a high spectral resolution rocket observation.

Pawlowski, David J.; Ridley, Aaron J. Modeling the thermospheric response to solar flares.

Sternovsky, Z.; Chamberlin, P.; Horanyi, M.; Robertson, S.; Wang, X. Variability of the lunar photoelectron sheath and dust mobility due to solar activity.

Leonovich, L. A.; Taschilin, A. V. Formation of negative disturbances in the topside ionosphere during solar flares.

Woods, Thomas N.; Chamberlin, Phillip C.; Peterson, W. K.; Meier, R. R.; Richards, Phil G.; Strickland, Douglas J.; Lu, Gang; Qian, Liying; Solomon, Stanley C.; Iijima, B. A.; and 2 coauthors. XUV Photometer System (XPS): Improved Solar Irradiance Algorithm Using CHIANTI Spectral Models.

Lu, G.; Goncharenko, L. P.; Richmond, A. D.; Roble, R. G.; Aponte, N. A dayside ionospheric positive storm phase driven by neutral winds.

Hock, R. A.; Eparvier, F. G. Cross-Calibration of TIMED SEE and SOHO EIT Irradiances.

Please note that the entire flare dataset is large, about 5GB. How long this may take to download will depend on a variety of factors, especially the bandwidth available at your site.

If you have any trouble downloading the data, please contact us for assistance.