NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center 1.SSTs for Daily SST OI NOAA’s National Climatic Data Center Asheville, NC OAA Climate Observation Program 4th Annual System Review Silver Spring, Maryland | May 10-12, 2006 Richard W. Reynolds (NOAA, NCDC)

Top: 2004 Anomaly Bottom: 2005 Anomaly Base Period: Differences –Slight change in weak ENSO –Shift in Tropical North Atlantic positive anomalies Similarities –Northern high latitude positive anomalies ~ 60°N SST Anomalies 2

Period: Jan '97 - Apr ' El Niño –Peak Jan 1998 Strong northern high latitude positive SST anomalies in Boreal Summers: '03 - '05 –Peak anomaly similar to ENSO but surface area smaller –'05 less intense than '03 and '04 Persistent modest northern middle latitude positive SST anomalies for record Zonal SST Anomalies 3 NOTE: Time

Period: Jan '82 - Apr ' , , , major El Niño events Northern high latitude positive SST anomalies –not evident before ~ 1997 Persistent northern middle latitude positive SST anomalies –not evident before ~ 1998 Clear evidence of warming trend with time between 20°S and 80°N Zonal SST Anomalies 4 NOTE: Time

Left:July - Sept '04 Right:July - Sept '05 Anomalies shaded Isotherms: 26-28ºC SSTs needed for hurricane formation: roughly > 26.5ºC Areas above 28ºC larger in 2005 than 2004 –Warmer anomalies tend to lie in these areas in 2005 Monthly SST 5 NOTE:

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center 2. Daily SST OI NOAA’s National Climatic Data Center Asheville, NC OAA Climate Observation Program 4th Annual System Review Silver Spring, Maryland | May 10-12, 2006 Richard W. Reynolds (NOAA, NCDC) Thomas M. Smith (NOAA, NCDC) Kenneth S. Casey (NOAA, NODC) Dudley Chelton (Oregon State University)

Top: AVHRR Pathfinder Bottom: AMSR-E For AVHRR: Absolute latitudes > 40° have roughly only 5 days of data Number of days increases toward the tropics Drop offs due to cloud cover For AMSR: Absolute latitudes > 40° have more than 20 days of data Drop offs due to precipitation in ITCZ and SPCZ Jan '03: Number of Days with Nighttime Obs on 0.25° grid 7

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Magnitude of Gradient: Gulf Stream Daily OI using AMSR-E for January - March 2003 Gradients have a stationary part due to topography –Thus, limited AVHRR data are useful

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center OI SST Analysis Weekly (OI.v2) Grid: 1 o Data: Satellite plus in situ (ship and buoy) data –Satellite data Infrared AVHRR –7-Day large-scale satellite bias correction for each satellite Spatial error correlation: ~ 700 km Daily Grid: 0.25 o Data: Satellite plus in situ (ship and buoy) data –Satellite data to include Infrared AVHRR Microwave AMSR-E –7-Day large-scale satellite bias correction for each satellite Spatial error correlation: ~ 100 km

AMSR-E has stronger standard deviations than Pathfinder –Especially in mid-latitude winter –Clouds reduce Pathfinder sampling These differences plus gradient differences suggest that separate Pathfinder OI and Pathfinder + AMSR OI needed Jan 2003: Standard Deviation Top: Pathfinder Bottom: AMSR-E 10

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Pathfinder Advantages: Lower bias variability; data delayed Operational Advantages: Real-time data; data Nighttime Zonal Bias: AVHRR - In Situ AVHRR Pathfinder - In Situ AVHRR Operational - In Situ 90N 90S 90N '82'05

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Weekly & Daily OI December Both OIs have bias correction for AVHRR data Daily OI uses Pathfinder Weekly OI uses Operational From the figure note: Operational data problem along 35 o S –Delayed mode processing allows data correction Daily scales reduced in high gradient areas

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Both OIs have bias correction for AVHRR data Daily OI uses Pathfinder Weekly OI uses Operational From the figure note: Pathfinder problem near equator in Eastern Pacific –Zonal bias in Pathfinder worse than Operational –Number of AVHRR retrievals lower than normal due to ENSO cloud cover Weekly & Daily OI January

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center OI Anomalies with Bias Correction January 1988: Along equator From the figure note: Operational AVHRR did not have strong biases in this region Negative biases in daily OI except at TAO mooring sites near: 155 o W, 140 o W & 125 o W OI bias correction fails to correct AVHRR Pathfinder satellite biases

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center OI Anomalies with Bias Correction January 1988: Along equator Daily OI computed with EOT bias correction From the figure note: Operational AVHRR did not have strong biases in this region Negative biases in daily OI except at TAO mooring sites near: 155 o W, 140 o W & 125 o W OI bias correction fails to correct AVHRR Pathfinder satellite biases Empirical Orthogonal Teleconnections (EOT) bias correction better at correcting biases

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Daily Bias Differences: 1 Jan ' Dec '04 EOTs reduce biases; Some residuals remain

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Daily OI: Ship Biases Satellite Biases are corrected with respect to in situ data (ships & buoys) Ships have larger random and bias errors than buoys –Ship observations using buckets tend to be biased cold due to evaporation –Ship observations using engine intake tend to be biased warm due to engine room heating –Ship metadata needs improvement Try to correct ship bias using buoy data –Preliminary tests indicate EOT procedures over a day time period would work

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Ship-Buoy SST Zonal Biases EOT monthly ship & buoy analyses Buoy SST obs increase with time –Significant buoy obs 1994 to present Care required to first correct in situ biases than satellite biases Easier to correct buoys with respect to ships than inverse NOT IMPLEMENTED !! Annual Ship - Buoy Bias Time '94 '05 60°S60°N

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Daily OI: Status Daily OI analysis computed on 0.25° grid with and without satellite EOT bias correction –Using Pathfinder AVHRR from 4 Jan 1985 to 31 December 2005 –Using Operational AVHRR from 1 Jan 2006 to present –Using AMSR-E from 1 Jun 2002 to 31 Dec 2005 –Using Pathfinder AVHRR & AMSR-E from 1 Jun 2002 to 31 Dec 2005 Future Plans –Add error estimate field to OI –Improve sea ice concentrations and generation of SSTs from sea ice –Put output files in NetCDF –Make OI operational

27 August: Katrina –Weak anomaly in Gulf in Path + AMSR-E 28 August: Katrina –Strong anomaly in Path + AMSR-E 29 August: Katrina –Strong anomaly in Path + AMSR-E –Modest anomaly in Path Daily OI SST Anomalies EOT satellite bias correction 20 Left:Pathfinder AVHRR OI Right: Pathfinder AVHRR + AMSR-E OI

NOAA Climate Obs 4th Annual Review Silver Spring, MD May 10-12, NOAA’s National Climatic Data Center Daily FTP OI Products AVHRR only –Pathfinder (Jan '85 - Dec '05) –Operational (Jan '06 - present) Dec '05Jun '02Present PathfinderOperational AVHRR + AMSR-E AVHRR Only PathfinderOperational Dec '05Jan '85 Present AVHRR + AMSR-E –Pathfinder (Jun '02 - Dec '05) –Operational (Jan '06 - present) –AMSR-E (Jun '02 - present) Test other data: TMI, ATSR, MODIS…