Welcome to our new Data Quality Assessment page for the EP/TOMS near real-time data. All of the NRT data are now archived at the GSFC DAAC, and the quality of the first two years of data is described in the EP/TOMS Data Products User's Guide. After some QC procedures are performed, each month of NRT data is archived at the DAAC. The purpose of this page is to keep data users abreast of current issues relating to TOMS instrument performance and calibration, algorithm performance, and any other issues pertaining to data quality.

TOMS is currently experiencing instrument problems. For more info please click here.

Until recently, the EP/TOMS are of continuing high quality that were consistent with the nominal uncertainties described in the accompanying pages.

Frequently asked questions regarding the Earth Probe TOMS near real-time data:

How does this year's ozone hole compare with previous years?

How do the current EP/TOMS ozone data compare with historical values?

What current geophysical events are affecting EP/TOMS data quality?

Does EP/TOMS have missing data, or data taken in an alternate instrument mode?

What is the current status of the EP/TOMS instrument calibration?

What effect do spacecraft attitude anomalies have on EP/TOMS data?