Objectives

The main purpose of the TROPESS project is to combine data from multiple satellites (including hyper-spectral thermal infrared, near-infrared, and ultraviolet instruments) to form a common retrieval framework to produce atmospheric composition measurements with accuracies superior to those derived from any single instrument.

Our three science questions are:

• How is Earth’s atmospheric composition changing over time?
• How are changes related in ozone and its precursors related in both space and time?
• How do changes in emissions (both direct and indirect) impact tropospheric ozone and its precursors?

The data produced by the TROPESS project will address science objectives in the following areas:

• Data assimilation
• Trend detection
• Anomaly detection
• Accuracy/Uncertainty estimation

The TROPESS data products will be rigorously validated using uncertainty analysis in conjunction with independent measurements. The data will be based on optimal estimation retrievals, which include critical diagnostics such as observation operators and uncertainty metrics succinct for assimilation into Earth system models. These steps will quantify the accuracies needed to compute long-term trends through multi-satellite records and chemical data assimilation.