1. NOAA/NESDIS/Center for Satellite Applications and Research
Toward a Long-Term Climate Change Monitoring in the JPSS Era Cheng-Zhi Zou
Thanks Bruce for the introduction. The title of my talk is ‘MSU/AMSU/SSU CDR development. I gave a talk three years ago in the STAR science forum about the MSU inter-calibration and trend and I kept talking this subject in the last few years in various occasions and hope people don’t get tired of it. But today I try to provide a comprehensive review of the current status and a discussion of various science issues include various bias correction, validation, inter-comparisons, web data support, and so on. I have reserved the room for two hours, but I will only talk about 45 minutes to one hour and allow plenty of time for questions. So don’t get scared about the length of the talk as suggested in the announcement.
NOAA/NESDIS/Center for Satellite Applications and Research
2016 STAR JPSS Annual Meeting, July 8-12, 2016

2. Outline The NOAA/NASA/MetOp POES Temperature Sounders
Current Capability at STAR
Applications of Atmospheric Temperature CDR
Perspective
Mitch provided long time support for project from the program side, such as leveraging funding.
And Fuzhong also provides program support and coordinate the CRTM team to work with our product development team. You may notice that most of my SDS science team members are from his Branch.
I also want to thank Changyong for his long time support from scince side. I can always count on his support when I need a discussion on science. even when I need support from his team members.

3. NOAA/NASA/MetOp Satellite Series Carrying Microwave/Infrared Sounders
MSU
SSU
AMSU-A
AIRS
ATMS
CrIS
AMSU-A
IASI
MWS
IASI-NG
Present

4. The NOAA/NASA/MetOp Temperature Sounders
MSU+SSU; AMSU-A
Have been measuring atmospheric temperature profiles from surface to stratosphere
Nearly 40 years of
observations with global
coverage
MSU : From surface to lower-
stratosphere
SSU: From mid-stratosphere to
lower-mesosphere
AMSU-A: From surface to upper-
This project focus on developing MSU/AMSU atmospheric temperature CDRs. The window channels will be addressed by another NOAA group.
In summary, we work on 15 atmospheric temperature channels, involving 15 satellites, with tempral coverage from late 1978 to present.
Each channel needs to be intercalibrated seperately.
With that, let me first talk about the MSU atmospheric temperature CDR development. The MSU started from 1978 on TIROS-N and ended on NOAA-14 in May So we don’t have MSU observations now. We have already completed the MSU CDR development and gained a lot of experiences. We have developed many new techniques for various bias correction procedure. So I am going to talk with more details on this instrument.

5. The NOAA/NASA/MetOp Atmospheric Temperature Souder Series
ATMS: From surface to upper-
stratosphere
AIRS/IASI/CrIS: From surface to lower-mesosphere
Pressure (hPa)
This project focus on developing MSU/AMSU atmospheric temperature CDRs. The window channels will be addressed by another NOAA group.
In summary, we work on 15 atmospheric temperature channels, involving 15 satellites, with tempral coverage from late 1978 to present.
Each channel needs to be intercalibrated seperately.
With that, let me first talk about the MSU atmospheric temperature CDR development. The MSU started from 1978 on TIROS-N and ended on NOAA-14 in May So we don’t have MSU observations now. We have already completed the MSU CDR development and gained a lot of experiences. We have developed many new techniques for various bias correction procedure. So I am going to talk with more details on this instrument.
Weighting functions of ATMS and AIRS

6. El Chichon (1982) Pinatubo (1991) El Nino (1998) El Nino (2010)
Current Capability at STAR – Merged MSU/AMSU-A Time Series (1978-present)
Here is mid-tropopshere, tropopause, lower stratosphere temperature trends derived from version 2 merged MSU/AMSU time series. The time period is from late 1978 to the end of Each pixel represents a 5-day averaged global temperatures for a particular MSU/AMSU instrument. Satellites are reprented using different colors. We can see the merging are very good, with point-to-point agreement. For TMT, the trend is about 0.15 K/dec, little trend in TTS, A -0.4 k/dec trend in TLS
The is mathematical chart for this transfer. The instrument is desinged that this transfer is very close to a linear. For purely linear calibration, the two calibration points will uniquely determine a linear calibration equation. However, in reality, the MSU instrument contains a week nonlinear term, with the magnitude is unknown. The uncertainty of this nonlinear magnitude caused a whole lot of problems for the trends. In our current calibration system, we use Simultaneous nadir overpass method to determine the nonlinear coefficients and the constant offset between different satellites.
El Chichon (1982) Pinatubo (1991) El Nino (1998) El Nino (2010)
Monthly and global-mean temperature anomaly time series, Updated and delivered to NCEI every month for ‘operationally’ archiving and distribution

7. AMSU-A Only Time Series (1998-present)
Similar procedure and Methodology
More channels and thus better vertical resolution
Shorter time period (1998- present)
Diurnal effect in stratospheric channels are larger and was removed

8. SSU-only Time Series (1978-2006)
SSU Temperature Anomaly Time Series
Before Recalibration (Raw Data) After Recalibration
So here is a summary that needs to be deal with in the MSU/AMSU reprocessing. These issues include, but are not limited to, ……….
In this talk, I’ll be focusing on the intersatellite biases and warm target temperature contamination; but also touch a little bit on other problems.
Recalibration successfully rehabilitated the SSU data record, making the inconsistent raw SSU time series
with large time-varying biases between satellites before correction (left) to a consistent, well-intercalibrated
and -merged satellite time series suitable for climate change studies after correction (right).

9. Merged SSU and AMSU-A Time Series (1978-present)
SSU time series after removing seasonal cycle
1) Time series are not linked to each other due to the cell pressure problems
Merged SSU and AMSU-A time series

10. Application -- Involves in Global Warming Debate
SSU time series after removing seasonal cycle
1) Time series are not linked to each other due to the cell pressure problems
Three groups, University of Alabama at Huntsville (UAH), Remote Sensing Systems (RSS),
and NOAA/STAR produce the same variable, Temperature of Mid-Troposphere (TMT),
but having different long-term trend values

11. Support Congress Hearing on Climate Change Debate
SSU time series after removing seasonal cycle
1) Time series are not linked to each other due to the cell pressure problems
Plot from Jan Congress Climate Change Hearing

12. Support NOAA and IPCC climate change assessment
IPCC provide climate change
assessment every few years
NOAA/NCEI provide climate
assessment every year
STAR data used as a reference
in characterizing atmospheric
temperature changes
SSU time series after removing seasonal cycle
1) Time series are not linked to each other due to the cell pressure problems
Global mean temperature time series in
Lower-troposphere and lower-stratosphere
(Plot from IPCC AR5 Report)

13. Monitoring Climate Change in Near Real Time
SSU time series after removing seasonal cycle
1) Time series are not linked to each other due to the cell pressure problems
1998 EL Nino
2016 EL Nino

14. Investigation of Climate Change Phenomenon —Temperature trends responding to ozone trends
Linear trends (K/Dec) and 2-sigma uncertainty of the residual time series after the 11-year solar cycle and aerosol effect were removed from the extended SSU global mean time series.
SSU Ch3
-0.64 (0.06)
-0.93 (0.10)
-0.39 (0.10)
SSU Ch2
-0.55 (0.06)
-0.88 (0.07)
-0.30 (0.10)
SSU Ch1
-0.48 (0.06)
-0.76 (0.07)
-0.25 (0.07)
SSU time series after removing seasonal cycle
1) Time series are not linked to each other due to the cell pressure problems

15. Validating Chemistry-Climate Model Simulations in the Stratosphere
Trends are nearly identical
for channels 2 and 3
Model cooling trends are
slightly weaker for channel 1
Solar cycle amplitude in
models is weaker

16. Spatial Trend Pattern of the Mid-Tropospheric Temperature
So here is a summary that needs to be deal with in the MSU/AMSU reprocessing. These issues include, but are not limited to, ……….
In this talk, I’ll be focusing on the intersatellite biases and warm target temperature contamination; but also touch a little bit on other problems.

17. Future Perspective
Present

18. Perspective
Merge ATMS channels 5, 7 and 9 to the existing MSU/AMSU time series for extended TMT, TUT, and TLS. This will extend the time series from to possibly 2038 in the JPSS era. The extended time series will span for over 60 years. It will provide more accurate estimate on tropospheric temperature trend: the typical time length for tropospheric temperature trend estimates with 20% error is about 35 years
Merge ATMS channels 4 through 14 to AMSU-A channels. This will extend the AMSU-A only time series from 1998 to The extended time series will span for 40 years with high vertical resolution for trend and variability studies
So here is a summary that needs to be deal with in the MSU/AMSU reprocessing. These issues include, but are not limited to, ……….
In this talk, I’ll be focusing on the intersatellite biases and warm target temperature contamination; but also touch a little bit on other problems.

19. Perspective
Merge ATMS channels to SSU/AMSU-A channels for extended TMS, TUS, and TSM. This will again extend the time series from 1978 to The extended time series will span for over 60 years with 6 complete solar cycles. This stratospheric temperature time series is expected to largely improve our understanding on the impact of the solar cycle and aerosol on the climate change
Merge AIRS/IASI/CrIS stratospheric channels to SSU channel 3. Since AMSU-A/ATMS channel 14 is not high enough to cover the lower- mesospheric layers that the SSU channel 3 was sensing, this merging will likely provide a more accurate SSU extended time series over the lower- mesospheric layers
So here is a summary that needs to be deal with in the MSU/AMSU reprocessing. These issues include, but are not limited to, ……….
In this talk, I’ll be focusing on the intersatellite biases and warm target temperature contamination; but also touch a little bit on other problems.

20. Preliminary Work on AMSU-A and ATMS Merging
In this talk, I’ll be focusing on the intersatellite biases and warm target temperature contamination; but also touch a little bit on other problems.
Plot showing effect of inter-satellite calibration between AMSU-A and ATMS
(from Zou X. et al. 2014)

21. Thank you!