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This CD-ROM contains the Second Edition of data pertaining to the Airborne Arctic Stratospheric Expedition (AASE) which was based in Stavanger, Norway during January and February, 1989. The First Edition of this dataset, produced in March 1990, was corrupted by many data errors introduced during production of the CD-ROM. The form of the errors was a random conversion of characters to spaces. All files in this Second Edition are identical to those in the First Edition with the following exceptions: (a) this README.DOC file; (b) the NPyymmdd.DC8 files have been revised to correct the problems with small negative longitudes; (c) the M489AASE.DC8 file containing the DC-8 Mark IV interferometer data has been revised. And hopefully the random data errors are not present in this edition.

The data consists of measurements collected onboard the NASA ER-2 and DC-8 aircraft, ozonesonde soundings from three stations (Angmagssalik and Scoresbysund, Greenland, and Lerwick, U.K.), aerosol and temperature profiles from the SAM II satellite, global grid point values of Nimbus 7 TOMS ozone, and selected radiosonde soundings from stations in the region of the experiment.

Theory teams provided calculations of: potential vorticity along the ER-2 flight path; cross-sections of potential vorticity, temperature, and geopotential heights along the DC-8 flight path; cross-sections of Clx, Fx, HCl, HNO3, and NOy along the DC-8 flight path; global grid point values of temperature, geopotential heights, and horizontal winds on selected pressure surfaces; northern hemispheric grid point values of potential vorticity and pressure on selected potential temperature surfaces.

And to whet the appetite of those seeking turbulence, two files of 5 Hz data from the ER-2 Meteorological Measurement System (MMS) have been included for flights during which mesoscale disturbances were observed. A separate CD-ROM containing all of the 5 Hz MMS data during the 1989 AASE (including the two files on this CD-ROM) is available as an appendix to this CD-ROM volume.

All files within this release are standard ASCII files with variable length records terminated by (ASCII decimal values 13 and 10). In general, the file naming convention uses a two character prefix to identify the measurement, followed by a six digit number giving the year, month, and day (GMT) of the flight (or balloon launch). To identify the measurement platform, a three character extension of ER2, DC8, or Bhh is used to denote the data is from the ER-2, DC-8, or balloon (hh denotes the GMT hour of launch). Exceptions to this convention are the data files for the DC-8 Mark IV interferometer (M489AASE.DC8) and the SAM II measurements (SAM2ARSL.DAT, SAM2TEMP.DAT) which contain all available data within a single file. The names of the files containing hemispheric and global grid point analyses are also exceptions in that the extensions are used to denote the potential temperature or pressure surface values of the analyses, and the TOMS data files have the extension of .DAT.


2.1 The DOCUMENT directory contains several files documenting the contents of this release.

2.1.1 CATALOG.DOC contains tables showing the available aircraft data and appropriate file name prefixes, the locations of the radiosonde stations, and brief descriptions of the available data.

2.1.2 CONTACT.DOC contains a list of names, addresses, and phone numbers of the principal investigators.

2.1.3 FORMAT.DOC gives the format specifications which all experimenters were encouraged to use when writing time series data files for data exchange. The standard format includes header information which describes the data, and the data in the form of time series. Some of the measurements (ie. balloon and lidar soundings, and those with nonuniform sampling intervals), and the grid data, are not easily cast as time series with constant sampling intervals so some of the data files have unique formats. But most of the ER-2 data files and many of the DC-8 files follow this standard format (with the exception that we have changed the file name extensions from A1 to ER2 or DC8). This document may serve as a guide for reading the data files.

2.2 The DATA directory has eight subdirectories for the ER-2, DC-8, SAM II, TOMS, 3-D analyses, 5 Hz MMS, ozonesonde, and radiosonde data files.

2.2.1 The ER2 subdirectory contains the available data collected onboard the ER-2 aircraft, and calculations of potential vorticity along the ER-2 flight path. Each file contains data for one flight so the data is organized by flight date.

2.2.2 The DC8 subdirectory contains the available data collected onboard the DC-8 aircraft, and calculated vertical cross-sections of potential vorticity, temperature, geopotential height, Clx, Fx, HCl, HNO3, and NOy along the DC-8 flight path. In general, each file contains data for only one flight so the data is organized by flight date. However, the file for the Mark IV Interferometer contains data for several flights in a single file. This exception has been placed in the DC8MISC subdirectory.

2.2.3 The SAM2 subdirectory contains the aerosol and temperature data from the SAM II satellite measurements. All available aerosol extinction data and temperature data each occupy a single file.

2.2.4 The TOMS subdirectory contains the total ozone data files from the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) - one file per day.

2.2.5 The O3SONDE subdirectory contains the ozonesonde data organized by launch site with one file for each ozonesonde sounding.

2.2.6 The RAOB subdirectory contains the radiosonde sounding data collected in Stavanger, Norway during the deployment. Each file contains all available soundings for a particular time period.

2.2.7 The ANALYSES subdirectory contains 12 Z analyses of meteorological parameters organized by the type of surface on which the analyses were done (isentropic and isobaric).

2.2.8 The MMS5HZ subdirectory contains two files of 5 Hz ER-2 MMS data.


Directory Structure for 1989 AASE CD-ROM










ER-2 data for 88-12-29


ER-2 data for 88-12-31


ER-2 data for 89-01-03


ER-2 data for 89-01-06


ER-2 data for 89-01-07


ER-2 data for 89-01-12


ER-2 data for 89-01-16


ER-2 data for 89-01-19


ER-2 data for 89-01-20


ER-2 data for 89-01-24


ER-2 data for 89-01-25


ER-2 data for 89-01-30


ER-2 data for 89-02-07


ER-2 data for 89-02-08


ER-2 data for 89-02-09


ER-2 data for 89-02-10



ER-2 data for 89-02-21 




DC-8 data for 89-01-02


DC-8 data for 89-01-06


DC-8 data for 89-01-09


DC-8 data for 89-01-11


DC-8 data for 89-01-14


DC-8 data for 89-01-17


DC-8 data for 89-01-19


DC-8 data for 89-01-24



DC-8 data for 89-01-29


DC-8 data for 89-01-31


DC-8 data for 89-02-02


DC-8 data for 89-02-05


DC-8 data for 89-02-07


DC-8 data for 89-02-09


DC-8 data for 89-02-15


M489AASE.DC8 (Mark IV Interferometer)


SAM II aerosol and temperature data


TOMS ozone data files




Angmagssalik ozonesondes



Lerwick ozonesondes 



Scoresbysund ozonesondes



radiosonde data





Potential vorticity and pressure analyses on isentropic surfaces



Temperature, geopotential, horizontal wind on isobaric surfaces



5 Hz ER-2 MMS data for selected flights

This documentation and the accompanying data files were compiled by:

Steven Gaines 

NASA Ames Research Center

M/S 245-3

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 only checked the data files for extraneous control characters, and the correctness of the file headers values defining the number of lines in the file header and the date. Therefore, if problems with the data are encountered please inform us or the appropriate principal investigator.