TRENDS '93 Data Files The TRENDS93 subdirectory in the anonymous FTP area contains 350 data files that collectively provide all the data that were presented in TRENDS '93: A Compendium of Data on Global Change, compiled by the Carbon Dioxide Information Analysis Center. The files range in size from 0.46 kB to 35.97 kB, totaling 1.28 MB. All data files are provided as ASCII files and reside in subdirectories (CO2, CH4, TRACE, EMISS, TEMP, and PRECIP) that correspond to the chapters in the book. Most files are arranged or formatted just as they appear in the data tables in TRENDS '93. By referring to the tables in TRENDS '93, users can interpret the contents and format of each data file provided in the subdirectories. All data values in these data files have the same units mentioned in TRENDS '93. If you need to receive a copy of Trends '93, please contact CDIAC (e-mail: cdp@ornl.gov; telephone: 615 574 3645). Files that are not formatted as shown in the document are described below. The naming convention used for the data files have the general form XXXXXXXX.YYY where XXXXXXXX represents the particular name of the station, country, principal investigator, or geographic region and YYY represents the page number in the TRENDS '93 document where the data are presented in tabular form. For example, data file 'brazil.580' contains the 1950-1991 CO2 emission estimates from fossil fuel burning for Brazil that are presented on page 580 of TRENDS '93. Format of files that deviate from the tables presented in TRENDS '93: For the non-ice core and non isotopic atmospheric CO2 concentration records (pages 16-192 in TRENDS '93), each data record in each file is formatted in the following 2 line format: YEAR JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ANN where: YEAR is the year of the record JAN - DEC are the monthly atmospheric CO2 concentrations or mixing ratios expressed in parts per million (ppm) or parts per million by volume (ppmv). Missing values are denoted by -99.99. ANN is the annual atmospheric CO2 concentration or mixing ratio expressed in ppm or ppmv. Missing values are denoted by -99.99. Change the following paragraphs Bob S. For the modern atmospheric CH4 concentration records (pages 262-371 in TRENDS '93), each data record in each file is formatted in the following 2 line format: YEAR JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ANN where: YEAR is the year of the record JAN - DEC are the monthly atmospheric CH4 mixing ratios or concentrations expressed in parts per billion (ppb) or parts per billion by volume (ppbv). Missing values are denoted by -999.9 or -999.99. ANN is the annual atmospheric CH4 mixing ratio or concentration expressed in ppb or ppbv. Missing values are denoted by -999.9 or -999.99. For the modern atmospheric CFC-11, CFC-12, and N2O concentration records (pages 396-471 in TRENDS '93), each data record in each file is formatted in the following 2 line format: YEAR JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ANN where: YEAR is the year of the record JAN - DEC are the monthly atmospheric CFC-11, CFC-12, or N2O mixing ratios expressed in either parts per billion or trillion (ppb or ppt). Missing values are denoted by -99.9. ANN is the annual atmospheric CFC-11, CFC-12, or N2O mixing ratios expressed in either parts per billion or trillion (ppb or ppt). Missing values are denoted by -99.9. For the atmospheric solar transmission and aerosol optical depth records (pages 479-494 in Trends '93), each data record is formatted in the following 2 line format: YEAR JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC where: YEAR is the year of the record JAN - DEC are the atmospheric transmission factors or aerosol optical depth anomalies, expressed as unitless quantities. Missing values are denoted by -9.9999 (for atmospheric solar transmission data) or by -9.99 (for aerosol optical depth data). Several data tables in the Precipitation chapter of Trends '93 contain blank fields in the case of missing or unavailable data. (This only occurs at the beginning or end of several series.) To facilitate users' numerical processing of these data, all blank fields in their corresponding data files in the PRECIP directory have been replaced by numeric missing indicators that are negative and "9"-filled. For example, in the tables of monthly and annual precipitation amount from the United States Historical Climatological Network (pp. 834-905 in Trends '93 and files karl.834--karl.903 in the PRECIP directory), the unavailable October, November, December, and annual precipitation amounts from 1992 have all been coded as "-999.9" If you have any questions about the data files provided in this subdirectory or need to receive a copy of Trends '93, please call Sonja Jones (423 574 3645) at the Carbon Dioxide Information Analysis Center.