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Do We Know the Temperature of Earth? Yes

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Do We Know the Temperature of Earth? Yes Do We Know the Temperature of Earth? Yes CERES CALIPSO Earth Radiation Budget IR and Earth Observing Average Radiant Space Average Surface Temperature Temperature ~ 254 K ~ 287 K (~14 C) How Well Do We Know the Surface Air Temperature of Earth? How Well Do We Know the Surface Air Temperature of Earth? Land Surface Temperature Record Thermometers, Sensors, and Measurement Error Sea Surface Temperature Record Ships, Buoys, and Measurement Error How Well We Know the Surface Air Temperature of Earth. Land Surface Air Temperature Record The Surface Air Temperature Anomaly Record ±(0.2-0.05) C ±0.2 C Published Sources of Error Random instrumental error Error Due to Changes in: •Station Siting •Measurement time •Instrumentation •Instrumental exposure Climatic Research Unit, University of East Anglia and Hadley Centre for Climate, UK February, 2011 data set http://cdiac.ornl.gov/ftp/trends/temp/jonescru/global.txt Urban Heat Islands But nothing about systematic sensor error P. Brohan, et al. (2006) "Uncertainty estimates in regional and global observed temperature changes: A new data set from 1850" J. Geophys, Res. 111, D12106 Instrumental Error in the Temperature Record “Liquid in Glass” (LiG) Thermometers By far the most common surface air temperature measurement instrument used globally over the entire 20th century Hg thermometers in Stevenson Screens (CRS) T Min T Max Butte County Fire Station The Ideal T dry bulb T wet bulb #41 near Nord, CA. LiG-CRS instrument has never been field-calibrated Instrumental measurement error has never been evaluated (including in the recent Berkeley Expert Systems Technologies (BEST) compilation) Systematic measurement error Systematic Measurement Error Sensor Shield Calibration Experiment: Univ. of Nebraska, Lincoln Major Impacts on Accuracy 1.Solar irradiance 2.Ground albedo 3.Wind speed • Too low 4.Electronic Instruments • Self-heating • Voltage errors • Response drift R. M. Young aspirated probe Stevenson Screen Standard Reference HMP45C platinum resistance thermometer (PRT) K. Hubbard and X. Lin (2002) Realtime data filtering models for air temperature measurements Geophys. Res. Lett. 29(10), 1425 Accuracy in Surface Air Temperature Sensors The Hubbard and Lin Experiment: How Effective are Radiation Screens Against the Effects of Sun and Wind? University of Nebraska, Lincoln Data taken: April through August 2000 Protocol: 1. Aspirated R. M. Young ref. Bias = 0.8 C Bias = 0.4 C ~(±0.1 C) σ = ±0.3 C σ = ±0.2 C 2. Experimental screens; PRT. 3. Simultaneous Measurement Bias = 0.1 C Bias = 0.2 C σ = ±0.2 C σ = ±0.2 C Bias = 0.4 C Bias = 0.3 C Screen-Induced Error σ = ±0.4 C σ = ±0.3C Test temperature minus R. M. Young temperature Side-by-Side Comparison of LiG/Stevenson and MMTS Carried out to obtain a “transfer function” for when the LiG instrument is replaced by the MMTS. The “TF” scales current temp. trend to past temp. trend. Transfer function is not a calibration Field calibration of a LiG thermometer in a Stevenson Screen: No Published Record Accuracy in Surface Air Temperature Sensors How Accurate are LiG thermometers in Stevenson screens? Parallel measurements CO State Univ. Ft. Collins Figure 3. MMTS – LIG temperature differences (Deg F) by month for the Nolan J. Doeskin (2005) The National Weather Service MMTS (Maximum- period Jan. 2002 through Dec. 2004 for Fort Collins, Colorado. Minimum Temperature System) -- 20 years after in 13th Symposium on LiG MMTS LiG MMTS Meteorological Observations and T − T = [(Ttrue +εsys ) − (Ttrue +εsys )] Instrumentation, Baker, C.B., Ed. (Amer. Meteor. Soc., Savannah, GA) LiG MMTS = [(Ttrue − Ttrue ) + (εsys −εsys ) LiG LiG T = Ttrue +εsys MMTS MMTS T = Ttrue +εsys LiG MMTS MMTS LiG = εsys −εsys + εsys = εsys Accuracy in Surface Air Temperature Sensors How Accurate are LiG thermometers in Stevenson screens? LiG minus MMTS (Doesken, 2005) MMTS Systematic Error (Hubbard & Lin, 2002) + Systematic Error: Systematic Error: LiG Thermometer in a PRT in a Stevenson Stevenson Screen Screen Mean bias = +0.25 C Mean bias = +0.26 C Sys. Error = ±0.31 C = Sys. Error = ±0.39 C Accuracy in Surface Air Temperature Sensors The Huwald, et al. Experiment Non-aspirated R. M. Young Sensor vs. sonic anemometer 5 February through 10 April 2007; Plaine Morte Glacier, Switzerland Bias = 2.0 C σ = ±1.3 C Bias = 0.03 C σ = ±0.3 C Bias = 0.7 C σ = ±0.9 C H. Huwald, C. W. Higgins, M.-O. Boldi, E. Bou-Zeid, M. Lehning, and M. B. Parlange (2009) Albedo effect on radiative errors in air temperature measurements Wat. Resour. Res. 45, W08431 What About Sea-Surface Temperatures (SSTs)? World Ocean = ~70% of the Global Surface = ~70% of Global Temperature In situ SST Measurements •Prior to ~1970: mostly bucket-dipped thermometers •~1970 to ~1990: mostly ship engine intake thermometers •After ~1990 : floating buoys and ship engine intakes Prof. Of Meteorology, Harvard University(1931- 1958), principal founder and first secretary (1919- 1954) of the American Meteorological Society. SST Calibration Experiment February-March 1924 RMS Empress of Britain Charles Franklin Brooks This 1926 study is the only comprehensive calibration of shipboard bucket SST measurements ever published Traditional Sea Surface Temperatures Canvas Bucket Errors Canvas Bucket Fuess surface ~1880-1970 thermometer ~1900 Caribbean C.F. Brooks RMS EoB 35° 30° 25° 20° 15° Grand Banks Wooden Bucket Lt. Cmdr. E.H. Smith 19th century Int’l Ice Patrol Modoc & Tampa Mid-Twentieth Century Sea Surface Temperatures C.F. Brooks RMS EoB 1926 Ship Intakes One trip of a Military Sea Transport Ship, Measurement Error: Engine Intake Temperature June-July 1959 Fuess Thermometer n = 48 n=56 Precision (±0.1 C) All trips, All ships insulated bucket thermometer (1963) J. Applied Meteorology 2, 417-425 Twelve US military ships, 2½ years, 6825 measurements, Eastern and Western Pacific Ocean Avg. bias: 0.33 C; avg. σ=±0.89 C; “without improved quality control, the sea temperature data reported currently and in the past are for the most part No other comprehensive study of adequate only for general climatological studies.” measurement error in ship SSTs Late-Twentieth Century Sea Surface Temperatures Ship Intake and Buoys William J. Emery, et al., investigated the temperature difference between paired ships or paired buoys at 0-50 km separation distance For d < 10 km, SST measurements are considered replicates. Ship separation: < 5 km Buoy separation: < 5 km Annual average Annual average standard deviation: standard deviation: ±0.54 C ±0.16 C Figure 11: Ship minus ship SST difference as a function Figure 5: Buoy minus buoy SST difference as a of separation distance (March 1996) function of separation distance (March 1996) Since 1979: Satellite infrared SST measurements are calibrated to floating buoys Emery, W. J., Baldwin, D. J., Schlossel, P., and Reynolds, R. W. (2001) Accuracy of in situ sea surface temperatures used to calibrate infrared satellite measurements J. Geophys. Res. 106(C2), 2385-2405. SST Measurement Methods 1850-2010 1850 through 1980: ship sea surface temperatures •1850-1880: wooden buckets •1880-1940: canvas buckets •1940-1970: canvas buckets and engine intakes •1970-1980: engine intakes and canvas buckets •1980-2010: buoys and engine intakes Figure 2b Annual number of SST observations per year by platform type expressed as a fraction of the total. Ship SST Measurements Figure 3a: Number of SST observations and measurement methods excluding drifters and buoys E. C. Kent, et al., (2005) “Effects of instrumentation changes on sea surface temperature measured in situ” WIREs Climate Change 1, 718-728 Weighted Systematic Measurement Error Algorithm Progress in Accuracy 1850-1899 1850-1899: ±0.73 C 0.3×LiG-CRS + 0.7×wooden (canvas) bucket 1900-1939 1900-1939: ±0.73 C 0.3×LiG-CRS + 0.7×canvas bucket 1940-1969 1940-1969: ±0.65 C 0.3×LiG-CRS+0.7×(0.5×canvas bucket + 0.5×Engine intake) 1970-1979 1970-1979: ±0.60 C 0.3×LiG-CRS +0.7×(0.25×canvas bucket + 0.75×Engine intake) 1980-1990 1980-1990: ±0.50 C 0.3×LiG-CRS+.7×(0.75×Engine intake +0.25×buoy) 1991-2000: ±0.36 C 1991-2000 0.3×(0.75×LiG-CRS +0.25×MMTS)+0.7×(0.25×Engine intake+0.75×buoy) 2001-2011 2001-2011: ±0.29 C 0.3×(0.5×LiG-CRS+0.5×MMTS)+0.7×(0.1×Engine intake+0.9×buoy) Accuracy in the 130-Year Surface Air Temperature Trend 131-year anomaly Record Average Systematic Error (∆C) Official 0.8±0.11 Corrected 0.8±0.64 Corrected Record Official Record These systematic error bars reflect a lower limit of physical uncertainty We literally do not know the shape of the true temperature trend line within the limits of the systematic error bounds At the End of the Journey It is clear that: Large systematic measurement errors make claims of an unprecedented increase in surface air temperature since 1850 … …entirely unreliable. Large systematic physical errors in GCMs make predictions of future Earth climate... …entirely unreliable Systematic errors have been systematically neglected by the AGW guild of climate scientists No scientific case establishing a human cause for recent global air temperature change Acknowledgements $upport For Reviewing parts of this work Funding Agencies Prof. David Legates None University of Delaware Foundational Grants Dr. David Stockwell None University of California San Diego Business Contracts Prof. Demetris Koutsoyiannis None National Technical University of Athens Under the Table Oil Company Slush Funds None Pat Frank’$ Deep Pocket$ The whole ball of wax Thank-you for your kind interest and attention H. Huwald, C. W. Higgins, M.-O. Boldi, E. Bou-Zeid, M. Lehning, and M. B. Parlange (2009) Albedo effect on radiative errors in air temperature measurements Wat.
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