EP-Adeos Comparison
Both the ADEOS and EP data set extend back to October of 1997. In addition both sets have been processed in terms of 9-day averages. Therefore, as a simple comparison of the data with an already reliable data set, we've compared the 9-day averages from ADEOS and EP/TOMS in six regions around the tropics. These regions, though somewhat large (generally 10x30 or 40 degrees), will give an understading of how the data sets vary locally.
For each of the six regions we've calculated the RMS between the two sets, as well as an average TTO value for each over the period from October of '96 through May of '97. The following table displays these values:
| REGION | LATITUDE | LONGITUDE | RMS | ADEOS AVG | EP AVG | |
| West Africa | 20W-20E | 0-10N | 4.67du | 28.91du | 29.59du | |
| South Africa | 10E-40E | 10S-0 | 4.54du | 24.57du | 26.95du | |
| South Amer. | 70W-40W | 10S-0 | 4.64du | 19.96du | 22.82du | |
| East Pacific | 110W-80W | 10S-0 | 3.63du | 18.3du | 19.54du | |
| Samoa | 175W-165E | 20S-10S | 4.44du | 14.12du | 12.4du | |
| Nairobi | 30E-40E | 5S-5N | 4.43du | 21.75du | 23.68du |
Plots:
The following plots contain data from 10/96-5/97, with each data point being a 9-day increment. There are a total of 28 points for each plot (actually 28 - 2 gaps = 26 points in all). The y values are in Dobson units. For the most part the plots show good agreement, though the problem areas occur right at the gaps in the data (namely to the right of each gap in many cases). While we are looking into the nature of these particular anamolies, we believe that overall the data is quite reliable.
