recent results from radiosondes and other observing systems
DESCRIPTION
Recent Results from Radiosondes and Other Observing Systems. Dian Seidel NOAA Air Resources Lab. Silver Spring, MD Workshop on Vertical Temperature Changes, Asheville, NC, 27-29 October 2003. Topics. Characterizing atmospheric temperature changes New NOAA radiosonde datasets - PowerPoint PPT PresentationTRANSCRIPT
Recent Results from Radiosondes and Other Observing Systems
Dian SeidelNOAA Air Resources Lab.
Silver Spring, MD
Workshop on Vertical Temperature Changes, Asheville, NC, 27-29 October 2003
Topics1. Characterizing atmospheric temperature
changes2. New NOAA radiosonde datasets3. Intercomparison of satellite and radiosonde
datasets4. Removing the stratospheric signal from
MSU2 data5. High elevation, surface, and free-air
temperatures6. Integrating proxies for tropospheric
temperature
Characterizing atmospheric temperature changes
• Linear trends are simplistic descriptors of temperature change
• Some temperature changes appear to be abrupt
• “Slopes and steps” models are almost as simple, but better characterize the data
• Quantitative temperature changes are very sensitive to the statistical model chosen
Surface (1900-2002)
1880 1900 1920 1940 1960 1980 2000 2020
T A
nom
aly
(K)
-4
-3
-2
-1
0
1
61.6%
69.9%
49.5%
70.7%
0.66K
0.87K
0.42K
0.87K
0.099 0.000 0.172 K/dec
0.063 K/dec
Data sources: GHCN and UEA
Troposphere - Raobs 850-300 hPa (1958-2001)
1950 1960 1970 1980 1990 2000 2010
T A
nom
aly
(K)
-4
-3
-2
-1
0
1
32.2%
32.4%
36.5%
41.8%
0.52K
0.49K
0.32K
0.35K
-0.094 0.089 K/dec
0.116 K/dec
Data sources: HadRT2.1s and LKS
Stratosphere - MSU 4 (1979-2001)
1975 1980 1985 1990 1995 2000 2005
T A
nom
aly
(K
)
-5
-4
-3
-2
-1
0
1
43.0%
35.9%
83.6%
86.8%
-1.13K
-1.03K
-0.82K
-0.88K-0.348
0.085 -0.006K/dec
-0.470 K/dec
Data sources: UAH ver. 5.0 and RSS
New NOAA radiosonde datasets
• 54-station network (Angell, J. Climate, 2003)
• Adjusted LKS 87-station network (Lanzante, Klein, Seidel, J. Climate, 2003)
• RATPAC – radiosonde atmospheric temperature products for assessing climate (not yet avail.)
Angell’s 63-to-54-station network
Identification of
anomalous stations
Effect of removing 9 stations
Lanzante-Klein-Seidel 87-station network
Sensitivity of trends to LKS adjustments
(solid)
blue 30-90Ngreen 30N-30S
red 30-90S
NOAA RATPAC
• ARL/GFDL/NCDC collaboration, supported by OGP/CCDD
• Uses LKS data as a core• Network expansion would introduce
more uncertainty• Extends beyond 1997 using first
difference method and postCARDS data• Relies on station history metadata to
identify break points
Intercomparison of satellite and radiosonde datasets
Seidel, Angell, Christy, Free, Klein, Lanzante, Mears, Parker, Schabel, Spencer, Sterin, Thorne, and Wentz (submitted to J. Climate)
Dataset Investigators & Institution Source
Angell-63 Jim Angell --- NOAA 63 raob stations
Angell-54 “ 54 raob stations
HadRT David Parker, Margaret Gordon, Peter Thorne --- Met Office
Global raobs CLIMAT
LKS John Lanzante, Steve Klein,Dian Seidel --- NOAA
87 raob stations CARDS
RIHMI Alex SterinAll-Russian Research Institute of Hydrometeorological Information
Global raobs CARDS
RSS Carl Mears, Frank Wentz, Matthias SchabelRemote Sensing Systems
MSU
UAH ver. D John Christy, Roy SpencerUniv. of Alabama in Huntsville
MSU
UAH ver. 5 “ MSU
1960 1970 1980 1990 2000 2010
-10.00.0
10.0
-0.50.00.5
-0.50.00.5
-0.50.00.5
-0.50.00.5
-1.0-0.50.00.51.01.5
-1.0-0.50.00.51.0
25.025.0
MSU 2LT
MSU 2
850-300 hPa
300-100 hPa(tropics)
100-50 hPa
MSU 4
-SOI
QBO
Multi-Dataset-Average Layer-Mean Time Series
Global 850-300 hPa
1960 1970 1980 1990 2000 2010
-0.50-0.250.000.25
-0.250.000.25
-0.250.000.25
-0.250.000.25
-0.250.000.25
-0.250.000.25
AVG
Angell-63
Angell-54
HadRT
RIHMI
LKS
Multi-Dataset Average and Differences from Average
Signals of large-scale climate variations
QB
O
0.00
0.02
0.04
0.06100-50 hPa MSU 4
Ang
ell-6
3
Ang
ell-5
4
Had
RT
RIH
MI
LKS
UA
H
RS
S
Had
RT
LKS
Pin
atu
bo
0.00.51.01.52.0
Ang
ell-6
3
Ang
ell-5
4
Had
RT
RIH
MI
LKS
UA
H
RS
S
Had
RT
LKS
EN
SO
0.000.040.080.120.16
19
76
-77
0.0
0.4
0.8
1.2
100-50 hPa
850-300 hPa
850-300 hPa
MSU 4
MSU 2
GLOBE NH SH TROPICS
-0.3
-0.2
-0.1
0.0
0.1
0.2
Angell-63Angell-54HadRTLKSRIHMI
1958-1997 300-100 hPaTemperature Trends (K/decade)
MSU 2GLOBE NH SH TROPICS
-0.2
-0.1
0.0
0.1
0.2
UAH MSU ver. D UAH MSU ver. 5 RSS MSU HadRT LKS
MSU 4
GLOBE NH SH TROPICS
-1.4
-1.2
-1.0
-0.8
-0.6
-0.4
-0.2
0.0
1979-1997 Temperature Trends (K/decade)
GLOBE NH SH TROPICS-0.20
-0.15
-0.10
-0.05
0.00
0.05
FULLLKS (87 stns)Angell-63HadATpostCARDS
Effect of Subsampling on1979-1997 MSU2 Trends
(K/decade)
Removing the stratospheric signal from MSU2 data
• Qiang Fu, Celeste Johanson, Steve Warren, Dian Seidel
• Submitted, do not cite• [email protected]
High elevation, surface, and free-air temperatures
• Motivated partly by observations of recent rapid glacial retreat
• Seidel and Free (Climatic Change, 2003)
• Pepin and Losleben (Intl. J. Clim., 2002)
• Climatic Change, 2003. Special Issue edited by H. Diaz
Mountain Ranges Sampled by Paired Radiosonde Sites
Mountain Minus Low SiteTemperature Difference Trend
Degrees per Decade
-1.5 -1.0 -0.5 0.5 1.0 1.50.0
Latit
ude
-40
-20
0
20
40
60SFCMTN1KM2KM
p value
0.0 0.2 0.4 0.6 0.8 1.0
• Ongoing work by Pepin incorporates surface station data and upper air data from radiosondes and reanalysis
• Glacial retreat, especially in tropics, may be more influenced by hydrologic changes than warming.
Integrating proxies for tropospheric temperature
• Total column water vapor (Wentz and Schabel, Nature, 2000)
• Tropopause height and pressure, particularly in the tropics (Randel et al., JGR, 2000; Seidel et al., JGR, 2001; Santer et al., JGR, 2003)
• Polar vortex (Frauenfeld and Davis, JGR, 2003; Angell, JGR, 2001)
• Others?
1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
1.5
1.0
0.5
0
-1.5
-1.0
-0.5
300 hPa Center ContourMidlatitude MSU 2LT
Dep
artu
re
END