Information about Online Data at SEC
Information about Online Data at SECAll data and information from the US Government is in the public domain and has no copyright restrictions. Acknowledgment of the source of that information, as suggested below, is appreciated:
Information from the Space Environment Center, Boulder, CO,
National Oceanic and Atmospheric Administration (NOAA), US Dept. of Commerce
June 19 -- To ensure continued operational monitoring of important energetic particle data, it is necessary to reassign primary/secondary designations for the GOES Space Environment Monitor (SEM) detectors. Beginning 1700 UTC on June 19, GOES 11 (105W) will become the primary satellite for protons. GOES 12 (75W) will continue as the primary satellite for magnetometer, X-ray, and electron measurements. GOES 10 (135W) will be the secondary satellite for all SEM sensors - magnetometer, X-ray, and energetic particles. Because of the degraded state of the proton data on GOES-10, its designation as the secondary source for proton data is a short-term solution. More permanent solutions have been identified and are being evaluated. Users will be notified when we define and schedule a permanent fix. For detailed information see GOES Satellite Changes
May 15 -- The GOES 10 energetic proton detectors are showing intermittent, high noise levels in the higher energy proton channels (greater than about 80 MeV). This pattern is similar to problems experienced on the GOES 12 EPS Dome detector prior its P6 and P7 channel failures earlier this year. The loss of the P6 and P7 channels significantly impacts SEC's integral proton flux products above about 10 MeV (e.g., >10 MeV, >50 MeV, and >100 MeV). Therefore, the energetic proton detectors on the GOES 8 satellite is being used for the next 2-3 month. For detailed information see GOES Satellite Changes
| Measurements | Primary |
Secondary |
|---|---|---|
| Proton | GOES 8 |
GOES 10 |
| Magnetometer X-ray Electron |
GOES 12 |
GOES 10 |
| Solar X-ray Imager | GOES 12 |
no secondary satellite |
April 8, 2003 -- GOES Satellite Changes -- SEC stopped using GOES 8 data. GOES 10 is now SEC's primary GOES satellite, with GOES 12 the backup for non-SXI data: magnetometer, XRS x-ray measurements, and energetic particles. SXI is only available from GOES 12. See the GOES Satellite Change web page.
November 4, 2002 Dr. Rodney Viereck, e-mail: Rodney.Viereck@noaa.gov
In October, 2002 SEC determined that its Daily GOES X-ray Background Flux calculation was incorrect. The values were corrected as of 22 October 2002. Archives of the daily background values both at SEC and at NGDC will be corrected in due course.
It was brought to our attention that the Daily GOES X-ray Background Flux calculation at the Space Environment Center (SEC) was not correct. The computed values seemed too high. After a quick look at the values and the original data, it was agreed that indeed, there was something wrong. Further investigation showed that the code used for calculating the background flux was using 5-minute X-ray data instead of 1-hour X-ray data.
Historical Note: The X-ray Background Flux was developed in the early 1980s as a measure of the background solar x-ray flux. The algorithm for calculating this daily background flux is weighted towards the middle of the day for time series analysis and for comparisons with the solar F10.7 flux index, which is measured at local noon.
Daily GOES X-ray Background Flux algorithm:
- The 24 one-hour X-ray 1-8Å values are divided into three 8-hour sections
- The minimum for each of these three 8-hour sections is determined; …call them min1, min2, and min3
- The average of the minima from the first and last 8-hour sections is calculated
min_avg = 1/2 (min1 + min3)- Daily Background X-Ray Flux is the smallest of min2 or min_avg
X-Ray_background = minimum of (min2 or min_avg)
This algorithm was implemented incorrectly, using 5-minute average values instead of 1-hour average values. Thus, the X-ray background was calculated using only the first two hours of the day. Most of the time, this provided values that were not far from the true background X-ray value, but when a long-duration flare occurred at the beginning of the UT day it could introduce significant errors of an order of magnitude or more. Further investigation uncovered that this error has been in place since at least 1987.
The daily X-ray background flux values have been corrected as of 22 October 2002. The archive of the daily background values both at SEC and at NGDC will be corrected in due course.
GOES X-ray Background Flux appears in several SEC products: Solar and Geophysical Activity Summary, Daily Solar Data , Yesterday's Space Weather Values , Preliminary Report and Forecast of Solar Geophysical Data
August 23, 2002 -- The USAF stopped producing the Magnetometer Analysis Reports, FOR SECONDARY STATIONS ONLY.
July 1, 2002 -- SEC stopped running the Operational Magnetospheric Specification Model. The Predictive MSM based on the Costello Geomagnetic Activity Index test product, is online.
May 24, 2002 -- The USAF stopped producing the Auroral Oval Analysis Plot and the 27-day Solar Radio Flux Forecast.
May 3, 2002 -- Solar Region Number Sequence -- The SEC Solar Region Number, currently at 9936, is expected to reach 10,000 in the next 60 days. SEC products will continue to use 4-digit region numbers, with leading zeros. The sequencing for Solar Region Numbers will be: 9998, 9999, 0000, 0001
SEC Space Weather Alerts were redesign to provide the following improvements:
- New message formats that enhance readability and support automatic decoding
- Alerts issued when a threshold is crossed, instead of after standard time intervals, or end of the event
- New "Summary" products issued after the end of some events
- New alerts that match higher thresholds defined in the NOAA Space Weather Scales
- Dynamic SEC Alerts web pages with current alerts status, displays of alerting data, links to related data, alert archive logs, and online help.
The WWV message format changed. See the WWV description web page. This affected all distribution methods: Web, Anonymous FTP, e-mail list server wwv-list, and NWS Direct Distribution Systems.
Space Weather products distributed on NWS Direct Distribution Systems have NWS header and minor format changes. Some users saw two new products: Space Weather Advisory Outlooks and Bulletins. See the Space Weather Products on NWS Direct Broadcast Systems web page. This affected subscriber of the SEC e-mail list server wwire-list and NWS direct distribution system users, including the NOAA Weather Wire Service
The Online Data pages collect and organize SEC's data and products by content using a variety of groupings. The objective is to provide customers a complete picture of the space weather data is available from SEC. Previously the SEC web site had data links on many web pages, but there was no comprehensive overview. Another problem in showing what is available at SEC is the large amount and variety of data, products, and formats. The new Online Data page and sub-pages divide the data and products into a number of groupings. The intent is to limit the customer's search to a subset of SEC data products.
The Online Data page has links to many sub-pages which contain tables of links to online data and products. Each sub-page is a special collection of like data. For example, there a Solar sub-page with tables of the Solar data at SEC, and there is a GOES Satellites sub-page of GOES data. All Data at SEC contains links to all of SEC's online data and products. Many of the new sub-pages are organized by type of product or data: Alerts and Forecasts, Models, Forecasts and Summaries, Indices, and Measurements (plots, lists, & images).
In addition to SEC links, there are some links to non-SEC space weather data providers. On the bottom of the main Online Data page, there is a table of Non-SEC Space Weather Data Sources. Also, the SEC data tables contain an Archive column with links to non-SEC organizations that archive that data.
Problem: Denied access to an SEC web page that starts with gopher://
Situation: Gopher is an application that provides a nicely formatted interface and access to the directories and files in on an Anonymous FTP site. Gopher has navigation directories with descriptive headings like Latest Space Weather Data instead of just latest. Files in various formats, like ascii text and gif, can be downloaded to the users own system. Unfortunately, users behind firewalls must setup special permissions to use gopher:// protocol.
Resolution: SEC developed alternatives to gopher:// protocol that provide similar directory pages and access to FTP files using web protocol. The top level gopher:// directory has been replaced with FTPMENU.
Replace gopher://sec.noaa.gov/11/xxx with http://www.sec.noaa.gov/ftpmenu/xxx
Replace gopher://sec.noaa.gov/00/dir/xxx.txt with http://www.sec.noaa.gov/ftpdir/dir/xxx.txt
gopher://sec.noaa.gov/11/latest/ /ftpmenu/latest.html gopher://sec.noaa.gov/00/latest/SRS.txt /ftpdir/latest/SRS.txt
Problem: Receive an error message when trying to access an SEC web page, especially when the problem persists for more than an hour.
Situation: SEC's web services are quite robust although intermittent errors and system problems do occur. Historically the web server up-time is more than 99%. However, when a web browser receives a failure notice it often caches this response and then continues to return the failure notice to the browser user instead of trying to reload the failed web page.
Resolution: There are several approaches to clearing a cached failure message:
- Force your browser to reload the failed page by using reload or shift reload.
- Clear your browser cache manually. On IE: Tools/Internet Options/Delete Temporary Internet Files. On Netscape: Edit/Preferences/Clear History.
Alerts and Forecasts - A table of SEC Alert and Warning products, and SEC products which contain forecasts of Space Weather data.
Archive - An archive source for this product or an archive of the data contained in the product.
ASC - The ACE Science Center (ASC) at www.srl.caltech.edu/ACE/ASC has an on-line archive of ACE data.
ASCII Text Lists - In Measurements tables, products are grouped by their format. ASCII text lists are simple text files. Most of the text files are in table format that is both human readable and a fixed format for machine decoding. The SEC generated lists follow a standard format conversion.
Dynamic - A dynamically updating web page, i.e. a web page that automatically refreshes with new information at a fixed interval with no user interaction.
Indices - A table of SEC products which contain standard space weather indices, e.g. sunspot numbers or 10.7cm solar radio flux.
Latest - The latest, most recently updated, version on this product.
Measurements - A table of SEC products which contain data from direct space weather measurements. Measurements tables are organized by the format of the products; Real-time Displays and Plots, ASCII Text Lists, and Solar Images
Models - A table of Space Weather products based on space weather models. Models which a summary of current conditions are called Nowcasts. Some models provide a prediction of future conditions.
NGDC - The National Geophysical Data Center (NGDC), the National Geophysical Data Center, archives Solar-terrestrial Physics data. Much of the real-time data received at SEC are archived both online and off-line by NGDC. However, the data are not archived in the SEC format.
No - This form of the data is not available at SEC or at another site that we are aware of.
Older - An online directory or web page for older, previously issued, products. The wording indicates how much older data is available. For example, "75 day" means that products issued in the last 75 days are available, "from 1999" means all products issued since January 1999 are available.
Readme - A descriptive text about the product with information such
as: contents, source, when the product is generated or issued, and sources for
further information. The
icon is a link to the descriptive text. "--" indicates no descriptive
text is available for this product.
Real-time Displays and Plots - In Measurements tables, products are grouped by their format. Products in the Real-time Displays and Plots section present data graphically. Real-time displays are web pages that update dynamically while plots refers to static plots that present either recent or past data. These products are bar graphs, line plots, or 2-D presentations.
Reports and Summaries - A table of SEC products which contain reports and summaries of Space Weather data.
Solar Images - In Measurements tables, products are grouped by their format. Solar Images are gif, jpg, or fits format files with images of the sun.
Title - The product Title of the product or a brief description of the data contained in the product. Products are ordered within the table by the speed at which they are updated or issued. The products which update fastest are first. Subheadings in the Title column indicates update rates, e.g. As Conditions Warrant, Daily or less, Weekly, Monthly, Longer.
Update - The product's update interval. For example, "5-min" means the product is updated every 5-min, "1st week of the month" means the product is updated once a month during the first week of the month.
"--"- Indicates no descriptive text is available for this product.
