The Canadian SHOW Instrument: Spatial Heterodyne Observations of Water in the UTLS and stratosphere.

Abstract:

Over the past two years the Canadian Space Agency (CSA) the University of Saskatchewan and York University have studied, designed and built both balloon and aircraft based versions of the Spatial Heterodyne Observations of Water (SHOW) instrument. SHOW observes spectra of water absorption features near 1.36 microns from limb scattered sunlight with vertical a resolution of 200m. The technique provides well resolved, vertical profiles of water vapour from just below the tropopause to 30 km. This paper will discuss the SHOW specifications.

The SHOW instrument was launched on a technology demonstration flight from the CSA balloon facility at Timmins, Ontario in the fall of 2014 onboard a CNES balloon and gondola. This test flight was successful and as a result, the CSA has provided further funds to place SHOW onboard the NASA ER-2 aircraft in the middle of 2016. This paper will discuss the preparatory work associated with this ER-2 flight including refurbishment of the hardware and the development of novel two-dimensional tomographic retrieval algorithms that optimize the return from the high spatial resolution SHOW measurements.

In addition, SHOW is currently being studied by the CSA to determine its applicability for deployment onboard a Canadian micro-satellite. This paper will also discuss how the water vapour retrieval algorithms for balloon and aircraft based versions of SHOW have been modified and studied for their use from a spacecraft version of the instrument.