Surface flux, Aerosol and Meteorology (SAM) files contain available surface
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| Link | Description | Example |
| Summary | Summary of Surface Flux/Aerosol/Meteorology files. | ---------- |
| Site List | A complete list of available surface sites. | ---------- |
| File availability | Quick search for available months for a given site. (See site list for a listing of all CAVE surface sites.) |
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| On-Line Plots | Summary tables of variables in each file and on-line plots. |
Example Table Example Plot |
| File Format | 1 File Per site/Per Month Explains the format of the binary file |
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| File Naming Conventions | How file names are defined and directory paths at FTP site. |
SURFRAD Example |
| Read Routines | Fortran 90 and IDL code to read binary SAM Files. | Fortran Code IDL Code |
| SAM Statistic Files | SAM data are averaged to 15 minutes. Standard deviations and 'N' kept in separate files. |
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| Referencing Data | Please reference data used appropriately. | ---------- |
| Access ftp data base |
Access ftp data base via the web from this link. |
Summary
CAVE surface observations consist of a host of radiometric, meteorological, and aerosol observations taken at a number of sites around the globe. A number of organizations and people have generously made their data available for dissemination through this web site. That data, generally arrives at 1 minute temporal resolution and for our purposes is averaged to 15 minute means. The data is rewritten as binary files, each file contains a header and all available data for a single site for a single month. These are then released via anonymous ftp along with programs to read the files. See the links above for lists of files at surface sites and an on-line plotting tool that prints summary tables of all variables available at a given site.
Surface Flux Aerosol & Meteorology (SAM) File Format
The SAM file is a binary (big-endian) file of fixed record length. It consists of a Header record that contains information regarding the surface site and a list of variables contained in each file. The remainder of a file contains one record for each available variable where each record is one month's worth of data for that variable. Figure 1 below shows this schematically.
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| Figure 1. Graphic showing Surface Aerosol Meteorology (SAM) file structure. |
Figure 2. List of commonaly available data in SAM files. |
Figure 2 lists the first 22 variables in every SAM file (identical in each SAM whether the surface site has recorded the data or not.) Most sites do not record all these varialbes. Some observe more. If a site has more data of interest, UV data at SURFRAD sites for instance, these data are include as "Extra" variables in records beyond #22. The number of extra variables in a file is recorded in the file header. For quickly determining available data at a site go to the SAM PLOT page where a summary table for all sites in the data base can be quickly accessed.
File Naming Conventions and Directory Paths at FTP Site
SAM files can be downloaded via anonymous FTP from www-cave.larc.nasa.gov then "cd" to public/cave/SAM. File are contained in subdirectories defined by data source. File names are dependent upon a unique 3-letter identifier for each site. See Site List for a global map and listing of all surface sites. Or just continue down to see a list of sites, their directory paths at the FTP site and their file names.File names are based on a set of unique 3-letter identifiers, the directory path at the FTP site is based on the data source as shown in the following table.
| CAVE File Naming Convention & FTP Path | ||
|---|---|---|
| Data from DOE Atmospheric Radiation Measurement (ARM) Program | ||
| File Prefix | Surface Site | Anonymous FTP path |
| arm_C01_ | ARM/SGP Central Facility | public/cave/SAM/ARM |
| arm_E01_ | Larned, KA | public/cave/SAM/ARM |
| arm_E02_ | Hillsboro, KA, Boundary Facility B01 | public/cave/SAM/ARM |
| arm_E03_ | LeRoy, KA | public/cave/SAM/ARM |
| arm_E04_ | Plevna, KA | public/cave/SAM/ARM |
| arm_E05_ | Halstead, KA | public/cave/SAM/ARM |
| arm_E06_ | Towanda, KA | public/cave/SAM/ARM |
| arm_E07_ | Elk Falls, KA | public/cave/SAM/ARM |
| arm_E08_ | Coldwater, KA | public/cave/SAM/ARM |
| arm_E09_ | Ashton, KA | public/cave/SAM/ARM |
| arm_E10_ | Tyro, KA | public/cave/SAM/ARM |
| arm_E11_ | Byron, OK | public/cave/SAM/ARM |
| arm_E12_ | Pawhuska, OK | public/cave/SAM/ARM |
| arm_E13_ | Lamont, OK | public/cave/SAM/ARM |
| arm_E15_ | Ringwood, OK | public/cave/SAM/ARM |
| arm_E16_ | Vici, OK, Boundary Facility B04 | public/cave/SAM/ARM |
| arm_E18_ | Morris, OK | public/cave/SAM/ARM |
| arm_E20_ | Meeker, OK | public/cave/SAM/ARM |
| arm_E22_ | Cordell, OK | public/cave/SAM/ARM |
| arm_E24_ | Cyril, OK | public/cave/SAM/ARM |
| arm_MAN_ | Tropical West Pacific, Manus Island | public/cave/SAM/ARM |
| arm_NAU_ | Tropical West Pacific, Nauru Island | public/cave/SAM/ARM |
| Data from WCRP Baseline Surface Radiation Network (BSRN) Program | ||
| File Prefix | Surface Site | Anonymous FTP path |
| bsrn_ASP_ | Alice Springs, Australia | public/cave/SAM/BSRN |
| bsrn_DAA_ | De Aar, South Africa | public/cave/SAM/BSRN |
| bsrn_FLO_ | Florianopolis, Brazil | public/cave/SAM/BSRN |
| bsrn_GVN_ | Georg von Neumayer, Antarctica | public/cave/SAM/BSRN |
| bsrn_LAU_ | Lauder, New Zealand | public/cave/SAM/BSRN |
| bsrn_LIN_ | Lindenberg, Germany | public/cave/SAM/BSRN |
| bsrn_NYA_ | Ny Alesund, Norway | public/cave/SAM/BSRN |
| bsrn_PAY_ | Payerne, Switzerland | public/cave/SAM/BSRN |
| bsrn_SBO_ | Sede Boqer, Israel | public/cave/SAM/BSRN |
| bsrn_SSV_ | Saudi Solar Village | public/cave/SAM/BSRN |
| bsrn_SYO_ | Syowa, Antarctica | public/cave/SAM/BSRN |
| bsrn_TAM_ | Tamanrasset, Algeria | public/cave/SAM/BSRN |
| bsrn_TAT_ | Tateno, Japan | public/cave/SAM/BSRN |
| Data from NOAA Global Monitoring Division (GMD formerly CMDL) Program | ||
| File Prefix | Surface Site | Anonymous FTP path |
| cmdl_BAR_ | Barrow, AK | public/cave/SAM/CMDL |
| cmdl_BER_ | Bermuda | public/cave/SAM/CMDL |
| cmdl_BOU_ | Boulder, CO (Boulder Tower) | public/cave/SAM/CMDL |
| cmdl_KWA_ | Kwajalein Island | public/cave/SAM/CMDL |
| cmdl_MLO_ | Mauna Loa, HI | public/cave/SAM/CMDL |
| cmdl_SAM_ | Samoa | public/cave/SAM/CMDL |
| cmdl_SPL_ | South Pole, Antarctica | public/cave/SAM/CMDL |
| Data from NOAA SURFace Radiation (SURFRAD) Program | ||
| File Prefix | Surface Site | Anonymous FTP path |
| surfrad_BON_ | Bondville, IL | public/cave/SAM/SURFRAD |
| surfrad_DRA_ | Desert Rock, NV | public/cave/SAM/SURFRAD |
| surfrad_FPK_ | Fort Peck, MT | public/cave/SAM/SURFRAD |
| surfrad_GWN_ | Goodwin Creek, MS | public/cave/SAM/SURFRAD |
| surfrad_PSU_ | Penn State, PA | public/cave/SAM/SURFRAD |
| surfrad_TBL_ | Boulder, CO (Table Mountain) | public/cave/SAM/SURFRAD |
| surfrad_SXF_ | Sioux Falls, SD | public/cave/SAM/SURFRAD |
| Data from Independent Stations | ||
| File Prefix | Surface Site | Anonymous FTP path |
| indoex_KAS_ | Kaashidhoo Island, Indian Ocean Experiment (INDOEX) | public/cave/SAM/INDPND |
| larc_COV_ | Chesapeake Lighthouse, Virginia Beach, VA (COVE) | public/cave/SAM/INDPND |
| unva_VAS_ | Valencia Anchor Station, Valencia, Spain | public/cave/SAM/INDPND |
| whoi_PCN_ | Woods Hole PACS Buoy North(10N, -125W) | public/cave/SAM/INDPND |
| whoi_PCS_ | Woods Hole PACS Buoy South(-3S, -125W) | public/cave/SAM/INDPND |
| whoi_NT1_ | Woods Hole NTAS I Buoy | public/cave/SAM/INDPND |
| whoi_NT2_ | Woods Hole NTAS II | public/cave/SAM/INDPND |
| whoi_ST1_ | Woods Hole Stratus I Buoy | public/cave/SAM/INDPND |
| whoi_ST2_ | Woods Hole Stratus II Buoy | public/cave/SAM/INDPND |
| whoi_ST3_ | Woods Hole Stratus III Buoy | public/cave/SAM/INDPND |
Surface Flux Aerosol & Meteorology (SAM) Statistics Files
Most data coming into our data base arrive as 60 second averages of 1Hz observations. For our purposes we average these data to 15 minutes (minutes 0 throug 14, 15 through 29, etc...) Often too, data might be missing. So, statistic files containing the standard deviation of the data over each 15 minute time period and the number of points that go into each 15 minute average are also maintained and made available for interested parties. The naming convention is the same execpt instead of "avg" they have "sts" before the version number.| File | File Name | ftp directory path |
| 15 minute average file | surfrad_FPK_200208.avg.v3.0 | public/CAVE/SAM/SURFRAD/ |
| Companions statistics file | surfrad_FPK_200208.sts.v3.0 | public/CAVE/SAM/SURFRAD/stats/ |
These files are found in a subdirectory name "stats" inside each program directory where the 15 minute average files are found. A program to read them is available:
readstats.f90
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Data/Web Questions:David Rutan Last Updated: 2008/05/02 NASA Privacy Statement Feedback on Langley Products and Services |