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DATA

Discover and download the Earth observation data you need from the broad catalogue of missions the European Space Agency operate and support.

  • Data - External Data (Restrained)

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    SciSat-1: ACE-FTS and MAESTRO

    SCISAT-1 data aim at monitoring and analysing the chemical processes that control the distribution of ozone in the upper troposphere and stratosphere. It provides acquisitions from the two instruments MAESTRO and ACE-FTS. MAESTRO: Measurement of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation. Dual-channel optical spectrometer in the spectral region of 285-1030 nm. The objective is to measure ozone, nitrogen dioxide and aerosol/cloud extinction (solar occultation measurements of atmospheric attenuation during satellite sunrise and sunset with the primary objective of assessing the stratospheric ozone budget). Solar occultation spectra are being used for retrieving vertical profiles of temperature and pressure, aerosols, and trace gases (O3, NO2, H2O, OClO, and BrO) involved in middle atmosphere ozone distribution. The use of two overlapping spectrometers (280 - 550 nm, 500 - 1030 nm) improves the stray-light performance. The spectral resolution is about 1-2 nm. ACE-FTS: Fourier Transform Spectrometer. The objective is to measure the vertical distribution of atmospheric trace gases, in particular of the regional polar O3 budget, as well as pressure and temperature (derived from CO2 lines). The instrument is an adapted version of the classical sweeping Michelson interferometer, using an optimised optical layout. The ACE-FTS measurements are recorded every 2 s. This corresponds to a measurement spacing of 2-6 km which decreases at lower altitudes due to refraction. The typical altitude spacing changes with the orbital beta angle. For historical reasons, the retrieved results are interpolated onto a 1 km "grid" using a piecewise quadratic method. For ACE-FTS version 1.0, the results were reported only on the interpolated grid (every 1 km from 0.5 to 149.5 km). For versions 2.2, both the "retrieval" grid and the "1 km" grid profiles are available. SCISAT-1 collection provides ACE-FTS and MAESTRO Level 2 Data. As of today, ACE-FTS products are available in version 4.1, while MAESTRO products are available in version 3.13.

  • Data - Fast Registration with approval (Restrained)

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    IKONOS ESA archive

    ESA maintains an archive of IKONOS Geo Ortho Kit data previously requested through the TPM scheme and acquired between 2000 and 2008, over Europe, North Africa and the Middle East. The imagery products gathered from IKONOS are categorised according to positional accuracy, which is determined by the reliability of an object in the image to be within the specified accuracy of the actual location of the object on the ground. Within each IKONOS-derived product, location error is defined by a circular error at 90% confidence (CE90), which means that locations of objects are represented on the image within the stated accuracy 90% of the time. There are six levels of IKONOS imagery products, determined by the level of positional accuracy: Geo, Standard Ortho, Reference, Pro, Precision and PrecisionPlus. The product provided by ESA to Category-1 users is the Geo Ortho Kit, consisting of IKONOS Black-and-White images with radiometric and geometric corrections (1-metre pixels, CE90=15 metres) bundled with IKONOS multispectral images with absolute radiometry (4-metre pixels, CE90=50 metres). IKONOS collects 1m and 4m Geo Ortho Kit imagery (nominally at nadir 0.82m for panchromatic image, 3.28m for multispectral mode) at an elevation angle between 60 and 90 degrees. To increase the positional accuracy of the final orthorectified imagery, customers should select imagery with IKONOS elevation angle between 72 and 90 degrees. The Geo Ortho Kit is tailored for sophisticated users such as photogrammetrists who want to control the orthorectification process. Geo Ortho Kit images include the camera geometry obtained at the time of image collection. Applying Geo Ortho Kit imagery, customers can produce their own highly accurate orthorectified products by using commercial off the shelf software, digital elevation models (DEMs) and optional ground control. Spatial coverage: Check the spatial coverage of the collection on a map available on the Third Party Missions Dissemination Service.