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3.4.2 EnviView

EnviView is a free application that allows to open any Envisat data file (Level0, Level1b, Level2 and auxiliary PDS data file), and to examine its content and the value of any given field in any data set (except raw source packets). It allows the basic visualisation of data through simple 2D graphs and a representation of the geographic coverage. It is also made possible to export data to HDF, ASCII or binary data files and to save the contents of a record as HTML text.


It is guaranteed to run on Unix, Windows and MacOS and potentially other platforms too. More information is available from the ENVISAT web site at
The User Manual of EnviView is available at:


The main steps for opening and visualising a dataset stored in a product are described below. They are based on the most recent version of EnviView, version 2.6.4. Examples are given for the access to a Level2 product, to a Level1b limb product, and to a Level1b transmission product.

In the description of the product content (see section 2.2.3 of this document) and in the IODD reference document, the unit and the possible conversion factor used to store the Data Sets are detailed. Unlike BEAT and the GOMOS products toolbox, EnviView does not take into account the conversion factor possibly used to store the data values and returns them as they are stored in the product. However, this possible conversion factor and the unit for each data set are given in EnviView windows detailing the data set content or plotting the data sets. Example for a Level2 product

The choice of the GOMOS product file to be opened is made by selecting File and Open in the main menu, then by selecting the file in the correct folder.


Information on the product content is then provided in a new window ("File View" window): the headers (main header and secondary header), the list of the MDS, of the ADS (containing additional information describing the data) and of the GADS, as well as the number of records and their size.

Information on the elements listed as above may then be obtained in a new window ("Record View 1" window) by double-clicking on the relevant name. By default, this information is provided for the first record of the data set. The record number may be changed (the number of records is given). All data set fields of the element are then listed along with information on their value and the units.

Details for record 1 of NL_TANGENT_LINE_DENSITY:

Details for record 90 of NL_TANGENT_LINE_DENSITY:

It is also possible to plot the field values by selecting View and New Simple Graph View. In the new window opened ("Simple Graph View 1"), the quantities to be plotted may be selected in the X field and Y field menus. Additional parameters may be changed: Y' field (allowing to plot a second quantity), the plotting symbols, and the number of records to be plotted on the same plot.

The following two figures plot the values of the NO2 line density and of the O3 local density respectively (scale on the left y-axis) as a function of the index record. The standard deviation of the main quantities are also plotted (scale on the right y-axis). The 79 records of the data set are plotted on the same figure.

The following figure plots the values of the O3  local density (scale on the left y-axis) and of the associated standard deviation (scale on the right y-axis) are  plotted as a function of the index record. The 79 records of the data set are plotted on the same figure. Example for a Level1b limb product

Selection of the limb product:

Information on the product content:

Details for record 1 of LIM_MDS:

Plot of the upper and lower background spectra after correction and of the corresponding error: Example for a Level1b transmission product

Selection of the transmission product:

Information on the product content:

Details for record 1 of TRA_TRANSMSSION:

Plot of the transmission and the corresponding PCD: