Abstract

Ozonesondes launched from Beijing, China, over a 3 year time period (September 2002 to July 2005) are used to evaluate the performance of ozone profile retrievals in the upper troposphere and lower stratosphere (UTLS) from two new spaceborne instruments, the Atmospheric Infrared Sounder (AIRS) on... Show moreOzonesondes launched from Beijing, China, over a 3 year time period (September 2002 to July 2005) are used to evaluate the performance of ozone profile retrievals in the upper troposphere and lower stratosphere (UTLS) from two new spaceborne instruments, the Atmospheric Infrared Sounder (AIRS) on the NASA Aqua satellite and the Microwave Limb Sounder (MLS) on the NASA Aura satellite. Since the Global Positioning System ozone sensors (GPSO3) used in Beijing ozonesondes are new, comparisons with simultaneously launched Vaisala ECC sensors, and comparisons with an ozonesonde climatology from Sapporo, Japan, are presented. The results show that although the new GPSO3 sensor has a positive bias (about 20 - 30%) below 200 hPa and a negative bias (about 5 - 10%) above 60 hPa relative to known sensors, the measured ozone variability is consistent with Vaisala ECC ozonesondes, particularly in the UTLS region. The GPSO3 ozonesonde profiles over Beijing are then used to evaluate coincident ozone profiles from AIRS version 4 retrieval and MLS version 1.5 retrieval. Qualitatively, both satellite data sets can reproduce the gradients and variability of ozone in the UTLS region. Quantitatively, the agreement between the AIRS and ozonesonde ozone profiles is largely within 10% in the UTLS region (from 400 to 70 hPa). The statistical difference between the retrieval and ozonesonde data is minimum in the vicinity of the tropopause. The MLS ozone profiles also show good quality in the UTLS region with the best performance between 147 and 46 hPa. Show less