Retrievals of Atmospheric Temperature and Water Vapor Profiles in the Arctic

We show that by incorporating brightness temperature measurements at off-zenith angles, the accuracy of linear statistical retrievals of temperature and water vapor density profiles can be improved. This improvement is limited to clear sky cases where measurements at all angles represent the same atmospheric conditions. We present contribution functions and error amplification factors to show how the off-zenith measurements affect the retrieval performance. We also show that by combining brightness temperature measurements near the 22.235-GHz water vapor line with measurements near the 183.31-GHz line into a physical retrieval, the accuracy of the retrieved water vapor density profile for very low water vapor conditions can be significantly improved