Disclaimer: This material is being kept online for historical purposes. Though accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers. Visit https://espo.nasa.gov for information about our current projects.




This CD-ROM contains data pertaining to the combined experiment: Airborne Southern Hemisphere Ozone Experiment; and Measurements for Assessing the Effects of Stratospheric Aircraft (ASHOE/MAESA). This experiment was conducted in four phases between March and November 1994 at NASA Ames Research Center, California; Barbers Point, Hawaii; and Christchurch, New Zealand. Most of the data are essentially in their final form, but additional calibrations are being done for some instruments. A second edition incorporating any changes to the datasets is anticipated in mid 1996.

The data consist of in situ and remotely sensed measurements collected onboard the NASA ER-2 aircraft; radiosonde, ozonesonde, and backscatter sonde balloon measurements; ground-based spectrometer and lidar measurements; and SAGE II satellite measurements. Theory teams provided calculations of: meteorological parameters in the form of partial hemispheric analyses, cross-sections along the ER-2 flight track, interpolations to the ER-2 flight path, and back- trajectories of selected parcels along the ER-2 flight path; photodissociation rates of selected chemical species along the ER-2 flight path; and cloud properties along the ER-2 flight track.

All investigators produced either measurements or modelling results, though not all products were submitted to the archive. If there is an investigation of interest for which no data is available on this CD-ROM archive, please feel free to contact the Principal Investigator directly. For example, Dr. D. Johnson, University of Wisconsin, has model results from his hybrid forecast model which he is willing to provide to people that contact him. The project handbook, included in the document directory and described below, describes all instrumental and theoretical investigations.

All files within this release are standard ASCII files with variable length records terminated by a carriage return/line feed pair (, ASCII decimal values 13 and 10). Therefore, MS-DOS users should be able to read them as they are, but UNIX and Mac users will have to strip off either the or the from each line to convert them to standard UNIX or Mac text files. Commercially available software, such as dos2unix and Apple File Exchange, exists to convert MS-DOS files to both UNIX and Mac files. DEC VMS users can define the files to have STREAM record formats.

The file naming convention uses a two-character prefix followed by a six digit number (yymmdd) giving the year, month, and day (UT) on which the data begins. For files pertaining to a particular ER-2 flight, such as those in the er2 subdirectory, the date in the file name is the UT date of launch. In some files, like those in the ground subdirectory, the data starts on the date in the file name but extends for many days. A three character extension is used to identify the measurement platform or source. Those with two digits (e.g. Bhh) indicate the UT hour to which the data pertains.


  • 2.1 The document directory contains several files documenting the contents of this edition.



  • 2.1.1 contact.doc contains an updated list of names, addresses, and phone numbers of the principal investigators and/or those responsible for generating the datasets in this release.
  • 2.1.2 EOM.ps is a PostScript file containing the End of Mission Statement for ASHOE/MAESA. This document summarizes the objectives and significant findings of the campaign based on preliminary analysis of the data during the field phase of the mission.
  • 2.1.3 er2table.doc contains a record of the available ER-2 datasets in tabular format.
  • 2.1.4 fltcat.doc contains a tabular summary of the ASHOE/MAESA flights, compiled by Adrian Tuck, ASHOE Project Scientist.
  • 2.1.5 forspec1.ps and forspec2.ps are PostScript files of the document entitled "Format Specification for Data Exchange" which defines the standard file formats in which all data are recorded. forspec1.ps contains the title page and table of contents; forspec2.ps contains the bulk of the document.
  • 2.1.6 handbook.ps is a PostScript file containing the project handbook. This document describes the mission objectives, mission plan, aircraft instruments, and theoretical investigations. It can be printed on a PostScript printer (67 pp.), but some PostScript previewers may have problems with some of the special characters within the document.
  • 2.1.7 uv_vis.doc, by Tom McElroy, contains a detailed description of the UV-Vis experiment, also known as the Composition and Photodissociative Flux Measurement (CPFM).
  • 2.2 The data directory has seven subdirectories for the ER-2, ground based spectrometers, LIDAR, GSFC model results, ozonesonde soundings, radiosonde soundings, and SAGE II satellite data files.


    • 2.2.1 er2 - contains the available data collected onboard the ER-2 aircraft, plus derived quantities pertaining to particular flights. Each file contains data for one flight beginning on the UT date indicated in the file name.
    • 2.2.2 ground - contains ground-based spectrometer measurements from Lauder and Campbell Island, New Zealand; and Arrival Heights, Antarctica. Each file contains data for many days.
    • 2.2.3 lidar - contains stratospheric LIDAR measurements from Lauder, New Zealand. Each file contains data for one time period.
    • 2.2.4 model - contains 00 Z and 12 Z analyses of meteorological parameters on isentropic and isobaric surfaces. From the GSFC Assimilation Model with each file containing analyses for one time period.
    • 2.2.5 o3sonde - contains ozonesonde and backscatter sonde soundings from Lauder, New Zealand and Macquarie Island, Australia. One sounding per file.
    • 2.2.6 raob - contains selected radiosonde soundings near the aircraft flight tracks. Each file contains one or more soundings at one or more locations for a particular time period.
    • 2.2.7 sat - sunrise and sunset vertical profiles from SAGE II satellite instrument, with several profiles per file.



  • README.DOC in top level directory
  • document
  • data
  • |-- er2
  • |-- ground
  • |-- lidar
  • |-- model
  • |-- o3sonde
  • |-- raob
  • |-- sat

This documentation and the accompanying data files were compiled by:

Steven Gaines
NASA Ames Research Center
M/S 245-5
Moffett Field, CA 94035-1000

Steve Hipskind
NASA Ames Research Center
M/S 245-5
Moffett Field, CA 94035-1000

We have left the quality control of the data to the principal investigators and have checked only the format of the data files. Therefore, if problems with the data are encountered, please inform us or the appropriate principal investigator.