Status of the Integrated Global Radiosonde Archive (Additional information on IGRA is available at https://www.ncei.noaa.gov/products/weather-balloon/integrated-global-radiosonde-archive) June 5, 2023, derived-POR data is not being updated on NCEI web page: Due to some technical issues that are being addressed, the derived-POR data is not being updated on the NCEI webpage. However, it is up-to-date and available via ftp using ftp.ncei.noaa.gov/pub/data/igra/ under derived-por/ January 25, 2023, upcoming change: During the first half of February, IGRA will change to version 2.2. With this new version, data back to 2014 will be supplemented with radiosonde reports received in the Binary Universal Form for the Representation of meteorological data (BUFR). For IGRA users, this means that records for stations that have transitioned fully to using the BUFR format can again be updated in IGRA. See the igra2-readme.txt file and the IGRA Product Description for additional details. Jun 27,2020, GTS decoding decoding bug fixed: Thanks to Dr John Smallwood at Mullard Space Science Laboratory, UCL, UK, a bug in GTS decoder has been found and fixed. For maximum wind reported in GTS PPCC, pressure is in tenths of a hectopascal but it was incorrectly decoded as hPa. GTS data since 2018 have been reprocessed; data before 2018 will be reprocessed in the next annual rebuild. May 28, 2020, IGRA-v1 is going to be offline In the coming months we will remove the IGRA-v1 from NCEI website. As the first step of this action, v1 has been moved to subdirectory v1/ToBeDeleted/ August 12, 2016, upcoming change: During the week of August 15, version 2 of IGRA will move from beta status to fully operational status. IGRA 1 will continue to be available to users for the foreseeable future, but will no longer be updated. If all goes according to plan, the transition will begin on August 16. By the end of the transition, users should find that the version 1 files will have been moved to subdirectory v1. During the transition, some or all of the files may appear in the IGRA directories, but, after August 15, users are advised to wait with using IGRA again until another update has been entered into this file indicating that the transition has been completed. See below for information on the difference between IGRA 1 and 2. September 11, 2014 Addition A beta version of IGRA v2 is now available, including sounding data, monthly means, derived parameters, station history information, and basic format documentation. IGRA 2beta is available in the FTP directory http://www1.ncdc.noaa.gov/pub/data/igra/v2beta/ or at ftp.ncdc.noaa.gov under pub/data/igra/v2beta. All other files in http://www1.ncdc.noaa.gov/pub/data/igra/ as well as the webpages at http://www.ncdc.noaa.gov/oa/climate/igra/ will continue to reflect IGRA 1 until IGRA 2 has completed NCDC's internal review process and been approved as NCDC's official replacement of IGRA 1. For more information on IGRA 2, see http://www1.ncdc.noaa.gov/pub/data/igra/v2beta/igra2-readme.txt . September 9, 2014, Update: 1. The annual reprocessing of data through the end of the last calendar year has been completed, and the data files in the data-y2d directory now begin with January 1, 2014. 2. As part of this reprocessing, previously missing data for December 14-31 of the years 2008, 2010, and 2012 have been restored. 3. Monthly-mean files now reflect the composited data rather than the uncomposited data as was inadvertently the case in the previous version. 4. The long-outdated Version 1 of the IGRA-derived parameters has been removed from this FTP directory. IGRA-derived parameters can be accessed in subdirectory derived-v2. July 3, 2014 Fix and Problem Notification: 1. Thanks to Mohamadou Abdoulaye Diallo at the University of Virginia, An error in the IGRA derived-v2 readme.txt was fixed: Column 9, previously listed as "virtual temperature gradient", should be variable VPTEMP for "virtual potential temperature". 2. It has also come to our attention that the monthly means in the monthly-por are based on the uncomposited rather than the composited datafiles. This status file will be updated when the issue is resolved, possibly later this month. This issue also affects any RATPAC stations that have composite dates from the mid-1990s onward in that the RATPAC series for these stations may be less complete than they could be. January 27, 2014: The missing IGRA data between January 7 and 17 have been filled in, and regular updates for IGRA have Been working properly again since January 18. January 17, 2014: Due to an unusually large file of GTS reports that was received from NCEP and "choked" the relevant ingest processing it NCDC, the IGRA 1 processing system has not had access to GTS data since January 9. A resolution is still being worked out, and it is hoped that IGRA updates will resume sometime within the next week. September 26, 2013: Effective on this date, IGRA data through 2012 have been reprocessed through the IGRA period-of-record quality assurance process (see Durre et al. 2006), and the year-to-date files now begin on January 1, 2013. January 6, 2011, new IGRA-derived data: Version 2 of the IGRA-derived sounding parameters is now available, containing a significant number of additional parameters. For details, see the readme.txt file in subdirectory derived-v2. The related webpage will be updated shortly. For the benefit of regular users, version 1 will continue to be available through March 31, 2011, as well. January 6, 2011, known uncorrected problem: Several users have identified stations in IGRA where wind speeds during January and February of the years 1975-1978 and 1981-1982 are an order of magnitude too large when compared with other data sources. Stations in Texas, Alaska, and the Canadian Arctic are known to be affected. Unfortunately, we are unable to address this issue at this time. It will, however, be rectified in the next version of IGRA. In the meantime, users are advised to look out for this issue at any IGRA station during the affected years and months and handle it as they see it. October 5, 2010: Thanks to Liangying Zhang of NCAR, the metadata for U.S. and Australian stations Have been updated. The 475 added or edited records are identified with an update date of 06/2010 and a reference of "Updated by NCAR/EOL". Updates are based on information received by NCAR from the U.S. National Weather Service and the Australian Bureau of Meteorology. April 29, 2010: An updated IGRA metadata file has been placed online. The main changes compared to the previous version include: - the addition of several thousand records; - a change in the format to accommodate instrument names up to 40 characters in length; - standardization of instrument names; - elimination of various format issues; and - enhanced documentation. For details, including a description of the new format, see http://www1.ncdc.noaa.gov/pub/data/igra/igra-metadata-description.txt. November 18, 2009, change: An error in The calculation of relative humidity in the IGRA-derived data files was fixed in the version that became available on 18 November 2009. The error was due to inadvertent premature rounding of the actual and saturation vapor pressures to the nearest 0.1 mb and the unintentional rounding of the relative humidity itself to the nearest whole percent rather than the nearest 0.1%. the impact of the error ranged from less than 1% under warm, moist conditions to a few tens of a percent when the saturation vapor pressure was less than 1 mb (i.e., under cold and dry conditions under which radiosonde humidity measurements are also not very reliable). At the same time, the precision of both the actual end saturation vapor pressures written to the output files has been increased from mb*10 to mb*1000 in order to achieve improved consistency between the vapor pressure and relative humidity values written. Users are cautioned, however, that this precision is not necessarily a reflection of the actual measurement precision of the instrument. Since the entire data set is re-created every day, both changes apply to all IGRA-derived data effective immediately, and returning users who may have been affected by the error can refresh their own holdings. Thank you to Penny Rowe and her colleagues for pointing out the issues. January 3, 2008, change: The following changes have been made to the format of the IGRA-derived data: 1. The missing value code for all variables has been changed from -9999 to -99999, so that it falls outside the range of possible values in all fields. Accordingly, calculated values that fall outside the range -99998 and 99998 are set to missing. 2. The fields for actual vapor pressure and saturation vapor pressure have been moved, such that they now immediately precede relative humidity. See the readme file in the subdirectory "derived" for specifics on the format of the derived data files. 3. When the saturation vapor pressure is 0, relative humidity is now set to missing rather than to 0. August 23, 2007, fix: 1. The pre-2006 monthly means, which had been lost during the last monthly update on August 5, have been restored and, as of August 23, they are based on IGRA version 1.2. 2. The files in the monthly-por and monthly-upd directories are now being compressed into .gz format as the sounding files have been since July. They can be uncompressed using a Windows unzip utility or the Linux/UNIX gunzip command. August 20, 2007, Problem: Due to an oversight, the changes that were made to the online sounding files in July were not applied to the monthly-mean files. As a result, the monthly files are currently still being compressed into .Z rather than .gz format, and the period-of-record monthly-mean files currently only contain data for 2006 and 2007. We will get the problem rectified as soon as possible and update and notify users of the fix via the status file. August 9, 2007, update: The igra-composites.txt file has now been updated to reflect the compositing performed as part of the last period-of-record reprocessing. See the readme.txt file for further details on the composites list. August 6, 2007, Fix: During the last period-of-record update in mid-July, the 1949-1973 data for 72249 had been lost. These data have now been restored. July 30, 2007, addition: Some parameters that have been derived from IGRA are now available in the subdirectory "derived" on the FTP site of IGRA. Parameters include, for example, potential temperature, relative humidity, and temperature gradient between consecutive levels and are computed for each suitable level available in IGRA. For details, see http://www1.ncdc.noaa.gov/pub/data/igra/derived/readme.txt. July 30, 2007, addition: Some parameters that have been derived from IGRA are now available in the subdirectory "derived" on the FTP site of IGRA. Parameters include, for example, potential temperature, relative humidity, and temperature gradient between consecutive levels and are computed for each suitable level available in IGRA. For details, see http://www1.ncdc.noaa.gov/pub/data/igra/derived/readme.txt. July 16, 2007, changes to create IGRA Version 1.2: 1. Data files are now compressed in GZIP format (creating files with the extension .gz) rather than by using the Unix "compress" command (which generates .Z files). The .gz files can be uncompressed, for example, using WINZIP or the Linux "gunzip" command. 2. The data through the end of 2006 that are contained in the period-of-record files in the data-por directory have been processed through the entire IGRA processing system, including those checks that cannot be run during the daily processing (see Durre et al. 2006). Accordingly, the year-to-date files in the data-y2d directory now begin with January 1, 2007. 3. The dates in the igra-composites.txt files have yet to be updated accordingly. November 2006 correction: The period-of-record monthly-mean files uploaded this past summer were found to be missing data for all inactive stations. The problem has been rectified, and the files now again contain data for all qualifying IGRA stations. See the readme file for more information on these files. July 2006, addition: The directory monthly-upd was added to the IGRA FTP directory. It contains files of monthly means for only the last full month of data available and is intended for users interested in only those monthly means that have newly become available in the past month. July 2006, change to version 1.10: 1. The entire period of record through December 31, 2005, has been reprocessed through the entire suite of quality control checks. The reprocessing permitted the application of checks for runs-in-time and temporal inconsistencies that cannot be applied during the daily updates and allowed for the use of climatologies and monthly median elevation statistics that have been updated using data from 2004 in 2005. As a result of this reprocessing, some values previously retained are now removed, and vice versa. The number of values deleted experiences a net change by approximately 7000, or 0.2% of the total number of values deleted. 2. The year-to-date files in directory data-y2d have been changed to begin on January 1, 2006, rather than January 1, 2004. 3. Monthly means have been recomputed using the reprocessed data. 4. The list of IGRA composites has been updated to reflect the period of record through December 31, 2005, and the last year of data in the IGRA station list has been updated to reflect data holdings as of July 2006. February 6, 2006: The paper describing IGRA has appeared in the January 1, 2006, issue of the Journal of Climate. See the references link on the IGRA homepage. January 27, 2006, addition: Station history information for IGRA stations is now available at the "metadata" link on the IGRA homepage. November 10, 2005, change: Inconsistencies between the country codes in the IGRA station list and those in the country code list were discovered and fixed today. August 2005, change: The files of monthly means are now sorted properly by station number and year. This fixes the issue of 2004+ data being appended to the bottom of files that was discovered in January 2005. July 18, 2005, addition: A paper providing an overview of IGRa (accepted by J. Climate) is now available in the FTP directory as igra.overview.pdf. July 18, 2005, change: The files containing lists of IGRA stations, country codes, and composite stations have been renamed to igra-stations.txt, igra-countries.txt, and igra-composites.txt in order to adhere to NCDC standards. June 29, 2005, changes (creating v1.02): 1. Reorganized FTP directory to provide all documentation in the main igra directory and streamline the data directories (see readme.txt). 2. Added stations 43599 (Gan, Maldive Islands) and 83779 (Marte, Brazil) to the IGRA station list. Processing of the two new stations began in February, and their data extend back to 2004. 3. In the station list, GUAN identifiers and periods of record were updated, and the 3-digit country codes were replaced with 2-character FIPS codes (see readme.txt) to conform with NCDC convention. May 21, 2005, discovery and fix: Fourteen extraneous station files were discovered in the data-por subdirectory under the IGRA FTP directory. These files have been removed. November 2004 addition: Beginning of near-realtime daily updates to the sounding data. October 2004 discovery: The Thai stations 48327 and 48407 have a tendency for reporting soundings whose launch time differs by 5-6 hours from their observation hour and, therefore, are elim`nated by the quality assurance process. The issue may be related to launch times being reported as local time rather than as UTC and will be addressed when the next version of IGRA is created. (During IGRA development, an analogous problem was noted at the South Pole Station (89009) for 2000 and 2001, prompting the exclusion of that station from the check for consistency between launch time and observation hour.) September 2004 addition: Beginning of monthly updates to the monthly-mean data. May 2004: Completion of the base version of IGRA 1.0 (through 2003)