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High Resolution Dynamics Limb Sounder

The High Resolution Dynamics Limb Sounder (HIRDLS) instrument provides measurements of temperature, trace constituents and aerosols from the middle troposphere to the mesosphere, with a key attribute of high vertical resolution. HIRDLS will also provide key measurements of atmospheric aerosols and cirrus clouds, as well as unique measurements of sub-visible cirrus.

Research Highlights

Useful Vertical Range and Estimated Accuracy of HIRDLS Data

This table briefly summarizes the useful vertical range and estimated accuracy for each HIRDLS data product. More...

Cirrus in the upper troposphere

This picture displays the frequency of occurrence of cirrus in the upper troposphere during April 2007 as observed by the HIRDLS and CALIPSO experiments. More...

Equatorial wave structure

Equatorial waves are waves that are trapped in the tropics and which can propagate only longitudinally and vertically. More...

Stratosphere-Troposphere Intrusions

Deep intrusions of tropospheric air into the lower stratosphere above the subtropical jet are consistently observed with Aura/HIRDLS. More...

Gravity wave momentum fluxes in polar regions

During the period around the 2006 Arctic sudden stratospheric warming (SSW), a substantial elevation of the stratopause occurred, first disappearing then re-appearing at a higher altitude. More...

Gravity wave momentum fluxes in monsoon regions

Measurements from HIRDLS are used to quantify gravity wave momentum fluxes generated from monsoon regions across the globe over the three years 2005-2007. More...

Tropospheric intrusion: April 2006

HIRDLS detected a tropospheric intrusion event during 2-4 April 2006. More...


HIRDLS data version V7 (level 2 profiles) and level 3 (gridded data) are available from the NASA Goddard Space Flight Center Earth Sciences (GES) Data and Information Services Center (DISC). For more information about these products and earlier data versions, please refer to Data products.


Data Description and Quality, Version 7 pdf.
HIRDLS/MLS Ice Water Content Data Description and Quality, Version 2 pdf.
Data Description and Quality, Version 6 pdf.


To view a collection of HIRDLS images, click here .


The HIRDLS Wiki pages were archived in December 2017 (52 MB).


New Release: V7 Aura-HIRDLS Levels-2 and 3 Atmospheric Products

The HIRDLS team is pleased to announce the release of Version 7 of Aura-HIRDLS Level-2 Atmospheric Profile products ‘HIRDLS2’ and Level 3 Mapped Atmospheric product ‘HIRDLS3’. It is expected that this will be the final version of HIRDLS data. These data are now publicly available from the NASAGSFC Earth Sciences (GES) Data and Information Services Center (DISC). HIRDLS data also are available in the United Kingdom and Europe from the British Atmospheric Data Centre (BADC). The Data Description and Quality document for V7 is available from those locations, and also from this HIRDLS site.

The Version 7 Level-2 data products (vertical profiles of geophysical parameters along the measurement track) derived from the HIRDLS latest improved algorithms (V7.00.00 and V7.05.00) include the newly added products H2O, N2O, NO2, and ClONO2. In addition the previously released temperature, geopotential height, and species O3, HNO3, CFC11, CFC12, NO2, N2O5, plus clouds, aerosol extinction, and Ice Water Content (joint with MLS)) are of better quality than previous versions. All products have a vertical resolution of 1 km, and are spaced approximately 100 km apart along the scan track. Examples of these data and some applications can be found at our HIRDLS Data Products.

The Version 7 L3 data products have been gridded using the Kalman filter technique described by Rodgers [2000], including the representation of the atmospheric variation on a latitude circle at each pressure level as a zonal mean and the cosine and sine coefficients of the first 7 wave numbers.


The HIRDLS (High Resolution Dynamics Limb Sounder) instrument is a 21 channel (from 6.12 to 17.76 microns) limb scanning infrared radiometer measuring emission from Earth’s limb. These measurements are inverted to yield global distributions of temperature, clouds, aerosols, and concentrations of gases at high vertical and horizontal resolution from the upper troposphere into the mesosphere.

HIRDLS is a joint project between the UK and USA. It was launched on the NASA Aura spacecraft on 15 July 2004. The Principal Investigators for the HIRDLS mission are US scientist John Gille, from the University of Colorado and the National Center for Atmospheric Research, and UK Scientist Lesley Gray from the University of Oxford.

HIRDLS data are processed at the HIRDLS Science Investigator-led Processing System (SIPS) in Boulder, Colorado.

Dr. John Gille
University of Colorado and NCAR
January 18, 2013