Atmospheric composition continues to be a key Earth science focus for international space agencies and research organizations. The target constituent varies depending upon the topic area of interest such as monitoring the ozone layer and the efficacy of the Montreal Protocol, assessing the influence of volcanic eruptions and large wildfires on the atmosphere, improving our knowledge of...
The composition of the Upper Troposphere and Stratosphere (UTS) plays a significant role in controlling the Earth’s climate, but there are still poorly explored feedbacks within the Earth System. This region is coupled to the surface and the free troposphere both dynamically and radiatively. Its composition is strongly affected by anthropogenic emissions of greenhouse gases (GHG) and pollution...
Fourier-transform infrared (FTIR) sounding of the thermal emission of the Earth’s atmosphere is a versatile tool to address multiple scientific questions with one single instrument. Broad spectral coverage in combination with high spectral resolution provide information on a variety of trace gases, temperature and clouds. In the last decades, airborne FTIR sounders have been deployed for...
A novel limb sounder for the measurement of temperature at the mesosphere and lower thermosphere boundary is presented. The instrument is designed to fly on Micro- and Nanosatellite platforms for the deployment in satellite constellations. The goal is to obtain a dense, 4-dimensional mesh of temperatures for resolving the small scale, time-varying waves that couple atmospheric regions....
The Changing-Atmosphere Infra-Red Tomography Explorer (CAIRT) is one of the four candidates for ESA’s Earth Explorer 11. This mission has been proposed in order to achieve a step change in our understanding of the coupling of atmospheric circulation, composition and regional climate. The CAIRT concept proposes to perform limb tomography of the atmosphere from the troposphere to the lower...
The HAWC (High-altitude Aerosols, Water vapour and Clouds) mission is a highly synergistic observing system that showcases three Canadian instruments: the Aerosol Limb Imager, the Thin Ice Clouds in the Far InfraRed Emissions (TICFIRE) instrument, and the Spatial Heterodyne Observations of Water instrument. The mission was selected as the Canadian contribution to NASA’s Atmospheric Observing...
HAWC (High-altitude Aerosols, Water vapour and Clouds) is a new Canadian mission with three instruments designed to measure aerosol, clouds, water vapour and radiation in the Upper Troposphere and Lower Stratosphere (UTLS). The Aerosol Limb Imager (ALI), focuses on aerosol and high clouds by taking two dimensional, multi-spectral images of Earth’s limb in the visible and near infrared to...
The Airborne Scanning Microwave Limb Sounder (A-SMLS) is an instrument designed to fly onboard the NASA ER-2 aircraft, making wide-swath vertical profile observations of the composition of the upper troposphere and lower stratosphere (~10 – 20 km altitude) at 340 GHz. Observing a ~300km-wide swath ahead of the aircraft in a 2D raster scan (azimuth and elevation), A-SMLS is designed to measure...
Characterizing the distribution and evolution of aerosol particles in the stratosphere (10-40 km altitude) is important for understanding their potential contribution to long-term climate through heating. Significant heating effects are also observed due to impulsive events such as volcanic eruptions and smoke plumes from large wildfires, which can have considerable economic consequences....
The Ozone Mapping and Profiler Suite (OMPS) that launched in November 2022 on the NOAA-21 satellite contains the second in a series of NASA Limb Profiler (LP) instruments to be launched through 2034. The NOAA-21 LP has the same basic design as the SNPP LP operating since 2012 but includes several enhancements to improve stray light performance, reduce noise, and remedy some troubling thermal...
Spaceborne observations have enabled critical insights into the behavior of Earth's atmosphere. Atmospheric limb sounding (viewing the atmosphere edge-on) offers good vertical resolution, and the long atmospheric path viewed provides a strong signal to noise for measurements of tenuous trace gases. We present an overview of the “Microwave Limb Sounder” (MLS) series of instruments, whose...
