You are here: Home >> Ongoing projects >> MIPAS

Ongoing projects

link
  • Print

 

Objectives

MIPAS on ENVISAT


Optimized Retrieval Model (ORM)

ORM Team

Latest News on Validation

Auxiliary Data for a Better Characterization of MIPAS Level 2 Products


MIPAS Dedicated Spectroscopic Database

Documentation

Final Report

 

 

  • Print

 

 

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is an high resolution Fourier Transform Spectrometer developed by ESA for the detection of limb emission spectra in the upper atmosphere.

MIPAS has been successfully launched on board Envisat-1, on 1st March 2002. It detects the atmospheric limb emission over a wide spectral interval in the middle infrared region.

Up to now MIPAS mission can be divided in 3 parts:

  • measurements from June 2002 to March 2004
  • measurements on August - September 2004
  • measurements from January 2005 on


The characteristics of the instrument that are common to the different periods of measurements are summarised in the following table:

Type
Parameters
Pointing

Instantaneous Field of View 3 x 30 km2 (height per width,
at 10 km tangent altitude)
Elevation pointing 5 ... 210 km (tangent altitude)

Spectral
Spectral range
 685-970 cm-1, 1020-1170 cm-1, 1215-1500 cm-1, 1570-1750 cm-1, and 1820-2410 cm-1

Radiometric
Radiometric sensitivity NESR
 50, 40, 20, 6 and 4.2 nW/cm2/sr/cm-1, respectively for the above spectral ranges

The characteristics distinguishing the measurements in the different periods are the spectral resolution and the # of spectra per standard elevation scan.

The measured middle infrared emission spectra contain features of most atmospheric constituents. Therefore, a series of spectra measured in the limb-scanning configuration can be processed to determine the volume mixing ratio profiles of numerous atmospheric trace species.

The retrieval of pressure and temperature, as well as the volume mixing ratio of six high priority species, namely O3, H2O, HNO3, CH4, N2O and NO2, are routinely performed in near real time.
Official Site: http://envisat.esa.int/instruments/mipas/





  • Print

 

MIPAS

 

logo_mipas

 

 

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is a limb-viewing infrared Fourier transform spectrometer measuring the atmospheric emission onboard the ESA ENVISAT satellite, launched in March 2002. MIPAS acquired atmospheric spectra sampled at 0.025 cm-1 from July 2002 to March 2004 (full resolution measurements), and since January 2005 has been operating at 0.0625 cm-1 sampling (optimized resolution measurements). For the operations with reduced maximum path difference, a new scenario was adopted that exploits the reduction in measurement time of each interferometer sweep and uses a finer vertical sampling. Due to instrument limitations, MIPAS operated with a reduced duty cycle between January 2005 and November 2007, but was successfully recovered back to the 100% duty cycle in December 2007.
 

The operational analysis of MIPAS measurements is performed by ESA in near real time. The operational products consist of the concentration vertical profile of six target species (H2O, O3, HNO3, CH4, N2O and NO2), together with the temperature and pressure profiles.

 

The algorithm that performs the L2 analysis (from calibrated spectra to vertical profiles), suitable for implementation in the ENVISAT Payload Data Segment and optimized for the requirements of speed and accuracy, was developed by an international consortium led by IFAC in the frame of the ESA- supported Study entitled "Development of an Optimized Algorithm for Routine p,T and VMR Retrievals from MIPAS Limb Emission Spectra". This code is called Optimized Retrieval Model (ORM) and is the scientific reference of the near real time operational code.

 

This project started in October 1995 and is now completed after the validation of the algorithm with the first measurements detected by MIPAS.

 

Since April 2002 a new project has started, entitled ‘Support to MIPAS level 2 product validation', whose objective is providing support to ESA in the assessment of the performance of MIPAS instrument and the quality of MIPAS data products, as well as investigating on possible improvements of the products.

 

The distribution of MIPAS L2 operational products by ESA has been interrupted since March 2004 due to delays by Industry in upgrading the operational code with changes required for handling the optimized resolution measurements. Recently a significant number of measurements (at least one day of measurements for each month from January 2005 to March 2010) has been processed by the ORM and distributed by ESA. Two validation datasets are available, one aligned with V5.2 of the operational code currently under development, one aligned with the next version of the operational code (V6.0), containing all improvements in the code coming from results of the validation activity performed in these years.

 

 

 

 

click below to enter the IFAC-CNR

 

MIPAS web site

 

 

www.ifac.cnr.it/retrieval

 

 

 

 

 

 

 

 

 

  • Print

The objective of this project is the development and validation of the scientific algorithm for the near real time Level 2 analysis of MIPAS measurements on ENVISAT . This algorithm, suitable for implementation in ENVISAT Payload Data Segment and optimised for the requirements of speed and accuracy, has been developed in the frame of the ESA- supported Study entitled "Development of an Optimised Algorithm for Routine p,T and VMR Retrievals from MIPAS Limb Emission Spectra". This code is called Optimised Retrieval Model (ORM) and performs in near real time the retrieval of pressure, temperature and volume mixing ratio of six high-priority species, namely O3, H2O, HNO3, CH4, N2O and NO2.

This Study started in October 1995 and is now completed after the validation of the algorithm with the first measurementts detected by MIPAS.

A new project has started, entitled ‘Support to MIPAS level 2 product validation', whose objective is providing support to ESA in the assessment of the performance of MIPAS instrument and the quality of MIPAS data products, as well as investigating on possible improvements of the products.