The OMI instrument can distinguish between aerosol types, such as smoke, dust, and sulfates, and measures cloud pressure and coverage, which provides data to derive tropospheric ozone.
OMI continues the TOMS record for total ozone and other atmospheric parameters related to ozone chemistry and climate. OMI measurements are highly synergistic with the other instruments on the Aura platform.
The OMI instrument employs hyperspectral imaging in a push-broom mode to observe solar backscatter radiation in the visible and ultraviolet. The hyperspectral capabilities improve the accuracy and precision of the total ozone amounts and also allow for accurate radiometric and wavelength self calibration over the long term.
The instrument is a contribution of the Netherlands's Agency for Aerospace Programs (NIVR) in collaboration with the Finnish Meteorological Institute (FMI) to the Aura mission.
OMI derives its heritage from NASA's Total Ozone Mapping Spectrometer(TOMS) instrument and the European Space Agency(ESA) Global Ozone Monitering Experiment (GOME) instrument (on the ERS-2 satellite). It can measure many more atmospheric constituents than TOMS and provides much better ground resolution than GOME (13 km x 25 km for OMI vs. 40 km x 320 km for GOME).
OMI is a key instrument on Aura for monitoring the recovery of the ozone layer in response to the phase out of chemicals, such as CFCs, agreed to by the nations of the world in the Montreal protocol and later modifications to it at Copenhagen and London.
OMI measures criteria pollutants such as O3, NO2, SO2, and aerosols. The US Environmental Protection Agency (EPA) has designated these atmospheric constituents as posing serious threats to human health and agricultural productivity. These measurements are made at near urban scale resolution and track industrial pollution and biomass burning.
OMI detects volcanic ash and sulfur dioxide produced in volcanic eruptions with up to at least 100 times more sensitivity than TOMS. These measurements are important for aircraft safety.
OMI measures ozone profiles (in the UV) complimentary to those measured by TES and HIRDLS (in the IR) and MLS (in the microwave).
OMI measures BrO, formaldehyde, and OClO which all play a role in chemistry of the stratosphere and troposphere.
OMI measures the total column amount of atmospheric ozone NO2 as well as lower atmospheric dust, smoke, and other aerosols.
The instrument observes Earth's backscattered radiation with a wide-field telescope feeding two imaging grating spectrometers. Each spectrometer employs a CCD detector.
Onboard calibration includes a white light source, LEDs, and a multi-surface solar-calibration diffuser. A depolarizer removes the polarization from the backscattered radiation.