Data
Data Access Summary
V12 is an "off-cycle" release due to anomalies with the SIM Digital Signal Processor (DSP) and Electrical Substitution Radiometers (ESRs). On Sept. 03, 2023, the TSIS-1 SIM Digital Signal Processor (DSP) stopped responding to ground commands. Command and control of the DSP was restored on Oct. 21, 2023. However, the post-anomaly checkout showed issues with the electric substitution radiometers (ESRs) in certain configurations. Due to these issues, there are temporal and wavelength gaps in V12 data longward of 1620 nm after Oct. 21, 2023 where the ESR data do not meet our accuracy standards.
The investigation into the ESR anomaly is ongoing, but we are optimistic that corrections for the anomalous ESR data taken after Oct. 21, 2023 are possible. However, corrected ESR data will be available no sooner than V13 (December 2024). We are aware of a ~500 parts-per-million (PPM) deficit in the post-anomaly 1800-2400 nm integrated ESR irradiance, this deficit will also be addressed in V13.
The Sept 2023 DSP anomaly prevented the planned October 2023 semi-annual Channel C scans from being obtained. As a result, users should expect slightly higher noise after Apr. 04, 2023 (the latest Channel C observations) in the V12 L3 data release. Additionally, the V12 degradation corrections differ significantly from previous versions due to increased solar activity during the Solar Cycle 25 maximum. TSIS-1 SIM data users are encouraged to review the V12 release notes for complete details.
Available Data Summary
| Data Product | Instr. | Time Cadence | Spectral Coverage | Spectral Resolution | Level | Ver. | Data Info | Full Mission Data Download Files | Interactive Access | File Readers (Listed by Language) | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total Solar Irradiance (TSI) | TIM | Daily | All | N/A | 3 | 4 | ? |  |  | IDL | ||
| TIM | 6-Hourly | All | N/A | 3 | 4 | ? | | IDL | ||||
| Spectral Solar Irradiance (SSI) | SIM | Daily | 200-2400nm | Varies 1-34nm | 3 | 12 | ? |
| | IDL | ||
| SIM | 12-Hourly | 200-2400nm | Varies 1-34nm | 3 | 12 | ? |
| IDL |
| Text file (ASCII) |
 | Zipped text file |
 | Zipped IDL save file |
| Interactive |
 | netCDF File |
Reading Data Files
The following reader is available for the data files in the table above:
- TSI and SSI Level 3 text file reader (code in IDL)
Quick Overview
The TSIS instrument suite produces two primary data products: Total Solar Irradiance (TSI) and Solar Spectral Irradiance (SSI) from 200 nm to 2400 nm. TSI data products are formulated using measurements made by the TSIS TIM instrument, and are available in both daily average and 6-hourly average formats. The SSI data product is comprised of measurements made by the TSIS SIM from 200-2400 nm.
TSIS data products are available for public access. TSIS data may be accessed from three different locations:
Location | URL | Content | |
| TSIS Web Site | Primary | This web page (table above) | Full product documentation and direct downloads |
| LISIRD Web Site | Alternate | http://lasp.colorado.edu/lisird/ | Solar irradiance data from TSIS and other missions via interactive tools and common interfaces |
| GES DISC | Archive | https://disc.gsfc.nasa.gov/datasets?project=TSIS | Archived Level 0 and science products |
Refinement of data processing algorithms and some on-orbit characterization of the TSIS instruments continue. Please read the release notes on the TSI and the SSI web pages for detailed quality information about the products you may be interested in.
Data Product Characteristics
Characteristic | ||
| Coverage | Full Solar disk | Full Solar disk |
| Temporal Characteristics | 6-Hourly and Daily | 12-Hourly Daily |
| Spectral Coverage | All wavelengths | 200-2400 nm |
| Spectral Resolution | Total Solar Irradiance | Instrument and wavelength dependent, 34 nm for SIM at 2000 nm |
| Key Geophysical Parameters | Total Solar Irradiance | Incoming Solar Irradiance |
| Absolute Accuracy (Relative Standard Uncertainty, 1 sigma) | 0.01% (100 parts per million) | Varies per spectral region, Please see TSIS Instrument Overview for measurement objectives and the SSI web page for current status. |
| Relative Accuracy | 0.001% (10 ppm) per year | Varies with spectral region, Please see TSIS Instrument Overview for measurement objectives and the SSI web page for current status. |
Science Data Processing
The TSIS Science Data System (SDS) performs all science data production activities. It consists of the hardware and software components necessary to generate, manage, and distribute all TSIS standard science data products. The TSIS SDS routinely produces total solar irradiance and solar spectral irradiance data products on a daily basis. The Science Data System utilizes raw spacecraft and instrument telemetry, routinely-maintained calibration data, and other ancillary information to produce and distribute a variety of data products that have been corrected for all known instrumental and operational effects.
Data processing is performed automatically with the production of data through Level 3 two to fourteen days after the data has been downlinked from the spacecraft, allowing for telemetry retransmissions and, in the case of SSI, time to collect complete spectral scans. TSI and SSI data products are made available to the public immediately after they are produced by the data processing system, following automated quality checks.
The data products are available by direct download or interactive access on the LISIRD Interactive Data Access web site, and are formally delivered to the GES DISC on a daily basis for long-term archival. Dissemination of TSIS data products via the TSIS website at LASP enhances convenience for users as data access methods are tailored to those most functional for retrieving TSIS solar irradiance data. The TSIS project at LASP indexes and maintains a full archive of data products, making possible various and flexible data access interfaces that are intended to provide added convenience to end-users. Configuration management of data is built into the TSIS data system, owing to integration of the TSIS data processing and dissemination components.