Orbital and Sampling Strategies for Accurately Determining the Diurnal Cycle of Upper-Air Temperature Using a Constellation of Small Satellites
Abstract
For the climate record, the long-term accuracy of tropospheric temperature retrieved from microwave sounders is largely limited by our lack of knowledge of the diurnal cycle of upper-air temperature. Sparse spatial sampling of in situ measurements necessitates satellite observations to determine the structure of the diurnal cycle on a global scale. Current satellite missions are limited in their ability to determine the diurnal cycle due to a combination of sparse temporal sampling and/or calibration uncertainties. Accurate determination of the diurnal cycle of key geophysical parameters is of interest for two reasons: 1) Investigating the flow of thermal energy on the diurnal scale; 2) enabling the construction of long-term climate records from measurements made at different times during the day. We present a simulation study of the ability of a constellation of instruments in high-inclination low-earth orbits to make an accurate measurement of the diurnal cycle in the presence of realistic "weather" noise determined from the analysis of 5 years of hourly climate-model output. We find that by using relatively few orbiters (2 or 3) in slowly precessing orbits, in conjunction with existing or planned operational instruments in sun-synchronous orbits, the diurnal cycle can be determined with unprecedented accuracy. The precessing orbiters also provide accurate intercalibration of the sun-synchronous orbiters via numerous and geographically/temporally distributed coincident measurements. The authors propose a constellation of SmallSat-based microwave sounders specifically designed to measure atmospheric temperatures with climate-quality stability and precision and to cross-calibrate the weather satellite constellation. This constellation will be called the Climate Monitoring Microwave Radiometer (CliMMR) mission. A brief overview of the CliMMR SmallSat and the associated mission will be presented.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.A41H0148M
- Keywords:
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- 0394 Instruments and techniques;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0399 General or miscellaneous;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3360 Remote sensing;
- ATMOSPHERIC PROCESSESDE: 3399 General or miscellaneous;
- ATMOSPHERIC PROCESSES