A Comparative Analysis of Data Derived from Orbiting MSU/AMSU Instruments

Abstract

AbstractSpencer and Christy of the University of Alabama in Huntsville (UAH) recently introduced a new method to process MSU/AMSU satellite brightness temperature data with their version 6 (v6) data. A comparison of UAH v6 north polar lower stratospheric (TLS) data with that from Remote Sensing Systems (RSS) is presented, indicating a possible bias between 1986 and 1988. Comparing UAH and NOAA Center for Satellite Applications and Research (NOAA) TLS data produces a similar result. An additional analysis utilizing midtropospheric (TMT) data also found a similar bias. Comparing the NOAA TMT data for the May 2016 release against UAH and RSS TMT evidenced another excursion, dated at the middle of 2005, that was corrected in later releases. These comparisons reinforce the concerns expressed by other analysts regarding the merging procedure for UAH v6, repeating similar concerns regarding the earlier UAH v5 products. Any biases in the UAH, RSS, or STAR products would impact the trends calculated for these products and could explain the differences between these trends. Biases in the UAH series would also impact the UAH TLTv6 lower-troposphere product, which is a linear combination of the UAH TMT, tropopause temperature (TTP), and TLS series.