Discrepancies between the MWRP and Skyrad IRT were observed in January. The MWRP IRT
readings were constantly higher than those of the skyrad IRT. Some changes were introduced to
the MWRP IRT to address the problem (see DQR D060602.2). On May 3, the IRT mirror was
replaced. After the change in the mirror, the MWRP IRT readings became about 5-8 C lower. On
June 3 the agreement between MWRP and Skyrad IRT became satisfactory (2-5 degree C
It is hard to numerically quantify the difference in the IRT readings caused by the change
in the mirror. We can only warn the user that between January 1 and June 3 the MWRP
readings are 8 to 15 degree higher than the skyrad IRT.