The Stratospheric Aerosol and Gas Experiment (SAGE) III instrument was deployed on the International Space Station (ISS) in early March 2017 and began routine measurements in June 2017. SAGE III retrieves profiles of temperature and pressure from multi-spectral measurements of the oxygen A-band absorption feature centered near 762 nm. The A-band is located in a favorable spectral region where...
Total ozone is a measure of the protection of the biosphere from UV radiation. Extratropical total ozone recovery trends of about +0.5%/decade are consistent with the continuous decline in stratospheric halogen loading since the middle 1990s as a consequence of the Montreal Protocol and its Amendments on phasing out ODS. Nevertheless, the recovery (or chemistry-related) trends in the northern...
Stratospheric ozone absorbs ultraviolet radiation that is harmful to life on earth. Ozone is a major driving force of atmospheric dynamic processes and is responsible for the radiative heating of the stratosphere. Due to anthropogenic emissions of ozone-depleting substances (ODS) the amount of
stratospheric ozone decreased substantially through the latter part of the 20th century and the...
The detection of random transients, arising from high energy particle hits on CCD pixels, bears significance for the OMPS Limb Profiler (LP) sensor and other limb scatter sensors of similar design. This is because majority of the LP science data products are derived from altitude normalized radiances where even small transients at normalization altitude can be significant. Results from a...
The combined effect of El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD)on the tropical Upper Troposphere Lower Stratosphere (UTLS) ozone is examined using the data from Microwave Limb Sounder (MLS) onboard Aura Satellite and ECMWF (European Centre for Medium-Range Weather Forecasts) ERA5 reanalysis. During the years of positive (negative) ENSO and IOD events, UTLS ozone mixing...
The Ozone Mapping and Profiler Suite’s Limb Profiler (OMPS-LP), built by Ball Aerospace, is a dedicated imaging spectrograph for measuring vertical ozone profiles. Two Limb Sensors are currently in orbit aboard the Suomi NPP and JPSS-2 (now NOAA-21) spacecraft with two more units slated to fly aboard JPSS-3 and JPSS-4. The Limb sensor measures the vertical distribution of ozone in the...
This presentation describes recent updates to the Gauss Seidel Limb Scattering (GSLS) radiative transfer model, and provides a preliminary assessment of the impact of those updates on the NASA OMPS LP aerosol extinction coefficient retrieval algorithm. This work builds upon the most recently-released aerosol extinction data product (Version 2.1), which provides retrievals at several...
Sulfur hexafluoride (SF$_6$) is a greenhouse gas that is emitted at the surface because of its use as an insulator in electrical transmission equipment and electronic devices. Since its quasi-linear emission growth and its very long lifetime, SF$_6$ can be used as a tracer for the Age of Air (AoA) to diagnose changes in the Brewer Dobson Circulation (BDC). The chemistry of SF$_6$ has been...
LOTUS (Long-term Ozone Trends and Uncertainties in the Stratosphere) is a SPARC (Stratosphere-troposphere Processes And their Role in Climate)-sponsored effort to foster collaboration between established and early career scientists around the world, with expertise in ozone observations, modeling, and trend tools, with an aim toward innovating new climate research that meets the needs of the...
The Limb Profiler (LP) instrument, part of the Ozone Mapper and Profiler (OMPS) Suite, is designed to measure ozone and aerosol vertical profiles in the stratosphere and to continue long-term ozone data records. The first OMPS LP instrument has been operating on the Suomi National Polar-orbiting Partnership (SNPP) satellite since 2012 and the second LP instrument on the NOAA-21 satellite was...
The OSIRIS instrument has now operated for over 20 years beyond its original two year lifetime and there are no technical reasons why it will not continue to operate for at least the next few years. The Team associated with this Canadian built instrument was part of the initial consortium of scientists that pioneered the concept of these ongoing Limb Workshops. This presentation will summarize...
Stratospheric aerosols play a key role in atmospheric chemistry and climate. They are considered a catalyst for ozone depletion, serve as condensation nuclei for polar stratospheric cloud formation, and, in large quantities, have a short-term impact on the Earth's radiative budget. The aerosol effects depend strongly on the aerosol particle size distribution (PSD). Despite its importance,...
On 15th Jan. 2022 the submarine volcano Hunga Tonga-Hunga Ha’apai (HTHH) injected approximately 0.5 Tg of sulfur dioxide into the stratosphere, but more significantly added 150-170 Tg of water vapor to the stratospheric background (over a 10% perturbation) in a matter of several hours. The sulfur dioxide rapidly converted to sulfate aerosol and along with water vapor, was transported around...
We have recently developed an algorithm to retrieve mid-stratospheric and lower mesospheric temperature profiles from the OMPS Limb Profiler (LP) sensor that has been flying on NOAA’s Suomi NPP Satellite since Oct 2012. The algorithm uses LP measured radiances at 11 wavelengths centered at 350 nm to retrieve atmospheric temperature profiles between 35-65 km at ~2 km vertical resolution with 1...
The SASKTRAN radiative transfer model has been used for over twenty years in the retrieval processes associated with the Canadian OSIRIS instrument in operation onboard the Swedish spacecraft Odin. It started as a single Rayleigh scatter model first developed in the mid-1990s and has evolved into something much more. This presentation will detail the latest SASKTRAN developments that make it...
During the twilight event the boundary between the illuminated and shadowed parts of the atmosphere shifts upward with the increasing solar zenith angle. This makes it possible to retrieve the vertical profile of aerosol extinction from the ground – based measurements of the twilight sky brightness as a function of the solar zenith angle, performed in a narrow field of view and a narrow...
The quasi-biennial oscillation (QBO) represents a significant component of atmospheric dynamic variability in the stratosphere. Disruptions in the regular, if complex, nature of the QBO observed beginning in 2015 have reduced the power of traditional modeling approaches using linear dimensionality reduction techniques, e.g. principal component analysis (PCA). While the use of additional...