My thesis abstract!

Finally, the latest draft of my abstract is ready, hope it makes sense :)
I really cannot wait to submit!
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Antarctic sea ice and its snow cover are integral components of the global climate system, yet many aspects of their vertical dimensions are poorly understood, making their representation in global climate models poor. Remote sensing is the key to monitoring the dynamic nature of sea ice and its snow cover. Reliable and accurate snow thickness data from an airborne platform is currently a highly sought after data product. Remotely sensed snow thickness measurements can provide an indication of precipitation levels. These are predicted to increase with effects of climate change, and are difficult to measure as snow fall is frequently lost to wind-blown redistribution,
sublimation and snow-ice formation. Additionally, accurate regional scale snow thickness data will increase the accuracy of sea ice thickness retrieval from satellite altimeter freeboard estimates.

Airborne snow depth investigation techniques are one method, providing a means for regional estimation of these parameters. The airborne datasets are better suited to validating satellite algorithms, and are themselves easier to validate with in-situ measurement. The development and practicality of measuring snow thickness over sea ice in Antarctica using a helicopter borne radar forms the subject of this thesis. The radar design, 2 - 8 GHz Frequency Modulated Continuous Wave Radar, is a product of collaboration and the expertise at the Centre for Remote Sensing of Ice Sheets, Kansas University.
This thesis presents a review of the theoretical basis of the interactions of electromagnetic waves with the snow and sea ice media. The dominant general physical parameters pertinent to electromagnetic sensing are presented, and the necessary conditions for unambiguous identification of the air/snow and snow/ice layers for the radar are derived. It is found that the roughness of the snow and ice surfaces are a dominant determinant in the effectiveness of layer
identification in this radar. Motivated by these results, the minimum sensitivity requirements for the radar are presented.

Experiments with the radar mounted on a sled confirm that the radar is capable of unambiguously detecting snow thickness. Helicopter borne experiments conducted during two voyages into the East Antarctic sea-ice zone show however, that the airborne data are highly affected by sweep frequency non-linearities, making identification of layering difficult. A model for the source of these non-linearities in the radar is developed and verified, motivating the derivation of an error correcting algorithm. Application of the algorithm to the airborne data set demonstrates that the radar is indeed receiving reflections from the air/snow and snow/ice interfaces.

Consequently, this thesis presents the first in-situ validated snow thickness estimates over sea ice in Antarctica derived from a Frequency Modulated Continuous Wave radar on a helicopter-borne platform. Additionally the ability of the radar to independently identify the air/snow and snow/ice layers allows for a relative estimate of roughness of the sea ice to be derived; this parameter
is a critical component necessary for assessing the integrity of satellite snow thickness retrieval algorithms such as those using the AMSR-E data product.

This thesis provides a description and solution or mitigation of the many difficulties of operating a radar from a helicopter-borne platform, as well as tackling the difficulties presented in study of heterogeneous mediums such as sea ice and its snow cover. In the future the accuracy of the snow depth retrieval results can be increased as technical difficulties are overcome, and at the same time the radar architecture can be simplified. However, further validation studies are suggested to better understand the effect of the heterogeneous nature of sea ice and its snow cover on the radar signature.