Toward Improved Satellite Measurement of Climate Trends in the Atmospheric Temperatures
This event has passed. See the seminar recording here:
Dr. Cheng-Zhi Zou
NOAA/NESDIS/Center for Satellite Applications and Research
Monday March 25, 2019, 12:00-1:00 PM
ESSIC Conference Room 4102, 5825 University Research Ct, College Park, MD 20740
Abstract:
Global warming theory predicts increasing surface and tropospheric temperatures and decreasing stratospheric temperatures when anthropogenic atmospheric carbon dioxide concentration and other greenhouse gases increase. Satellite-borne sensors are the only means available for providing global temperature observations in the atmosphere for climate trend monitoring and verifying the global warming theory. During the past two decades, scientists have been developing atmospheric temperature climate data records (CDRs) using satellite observations from the Microwave Sounding Unit (MSU), Advanced Microwave Sounding Unit- A (AMSU-A), and Stratospheric Sounding Unit (SSU) onboard NOAA/NASA/MetOp historical and currently operational polar-orbiting satellites. These CDRs allow scientists to study the size, significance, and causes of the global atmospheric temperature trends and variability, to evaluate climate model performance, to assess the consistency between observed surface and tropospheric temperature changes, and to investigate the impact of ozone depletion and recovery on the stratospheric temperature changes. Overall, atmospheric temperature CDRs provided improved understanding on the anthropogenic impact on climate change.
Changes in diurnal sampling over time and calibration drift have been the main sources of uncertainties in the satellite measured temperature trends. We have recently examined observations from the Advanced Technology Microwave Sounder (ATMS) that has been flying onboard the NOAA/NASA Suomi National Polar-orbiting Partnership (SNPP) environmental satellite since late 2011. The SNPP satellite has a stable afternoon orbit that has close to the same local observation time as NASA’s Aqua satellite that has been carrying the heritage microwave sounder, the AMSU-A, from 2002 until the present. The similar overpass timing naturally removes most of their diurnal differences. Direct comparison of temperature anomalies between the two instruments shows little or no relative calibration drift for most channels. Our results suggest that both ATMS and AMSU-A instruments have achieved absolute stability in the measured atmospheric temperatures within 0.04 Kelvin per decade.
The high radiometric stability in the SNPP/ATMS and Aqua/AMSU-A observations could have broad implication and impact on the climate trend observations from the microwave sounders as well as other instruments. It provides an opportunity for using these instruments as references to calibrate and recalibrate other observations and help resolve debates on observed differences in the climate trends. In this talk, we review the status of the currently available atmospheric temperature CDRs in climate change detection and present detailed analyses of the radiometric stability in the SNPP/ATMS and Aqua/AMSU-A observations. We discuss why and how these instrument observations could be used as references for improving the accuracy of CDRs in climate change monitoring. We present examples in using these reference observations to recalibrate microwave sounders onboard other satellites and provide a perspective on future applications of such a concept.
Bio-sketch:
Cheng-Zhi Zou is a Physical Scientist at the NOAA/Center for Satellite Applications and Research (STAR) located in College Park, Maryland. Dr. Zou received his PhD from the University of Oklahoma in 1995 and worked in NOAA/STAR since 1997. He has been mainly engaged in measuring long-term changes in the atmospheric temperatures using satellite observations and evaluation of data products for climate change studies from different sources including those from satellite retrievals, climate reanalyses, and climate model simulations. He has developed a set of atmospheric temperature climate data records capable of detecting climate trends from the lower troposphere to the upper stratosphere during the satellite era. He conducted satellite retrievals to derive climate products such as polar winds. He also collaborated with colleagues on using mesoscale models to simulate and analyze a variety of atmospheric clouds and costal wave phenomena observed by satellites. He has published over 50 articles in AMS, AGU, and other leading journals including Nature, Science, and PNAS. He has received Department of Commerce Silver Medal Award and NOAA Administrator’s Award for advancement of satellite calibration and development of atmospheric temperature climate data records. He is a referred reviewer for many journals in the atmospheric science field.
Webex info:
Event site: http://go.umd.edu/zou
Event number: 733 598 601
Event password: essic
——————————————————-
To join the online event
——————————————————-
1. Click here to join the online event.
Or copy and paste the following link to a browser:
https://umd.webex.com/umd/onstage/g.php?MTID=e4b9d9dd49b9977182553eca426852542
2. Click “Join Now”.
——————————————————-
To join the audio conference only
——————————————————-
US Toll: +1-415-655-0002
Global call-in numbers:
https://umd.webex.com/umd/globalcallin.php?serviceType=EC&ED=769043492&tollFree=0
Access code: 733 598 601
——————————————————-
For IT assistance
——————————————————-
Travis Swaim: tswaim1@umd.edu
Cazzy Medley: cazzy@umd.edu
Follow ESSIC:
ESSIC homepage: http://essic.umd.edu/
ESSIC seminar calendar: MSQ-4102; http://go.umd.edu/essicseminar
ESSIC twitter: http://twitter.com/ESSICUMD
ESSIC facebook: http://facebook.com/ESSICUMD
ESSIC seminar coordinator: Dr. John Yang, jxyang@umd.edu