# Presentation: 844198

## 1.	SSTs for 20052.	Daily SST OI 

**1.****	****SSTs for 2005****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)**

## SST Anomalies  

**Top:   ****	****	****2004 Anomaly**** **
**Bottom: ****	****2005 Anomaly**
**Base Period****: 1971-2000**
**Differences**
**Slight change in weak ENSO**
**Shift in Tropical North Atlantic positive anomalies**
**Similarities**
**Northern high latitude positive anomalies     ~ 60****°N**

**SST Anomalies **** **

## Zonal SST Anomalies  

**	****Period:  Jan '97 - Apr '06**
**  **
**1997-98 El Ni****ñ****o**
**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 **** **

**NOTE:**

- Time

## Zonal SST Anomalies  

**	****Period:  Jan '82 - Apr '06**
**  **
**1982-83, 1987-88, 1997-98, major El Ni****ñ****o 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 **** **

**NOTE:**

- Time

## Monthly SST   

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

**Monthly SST  **** **

**NOTE:**

## 2. Daily SST OI 

**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)**

## Jan '03:  Number of Days with Nighttime Obson 0.25° grid 

**	****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**** **

## Magnitude of Gradient:Gulf Stream 

**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

## OI SST Analysis

| Weekly (OI.v2)
Grid: 1o 
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: 0.25o 
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  |
| --- | --- |

## Jan 2003:  Standard Deviation

- 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 **

## Nighttime Zonal Bias: AVHRR - In Situ

-  Pathfinder Advantages: 	Lower bias variability; data delayed
-  Operational Advantages: 	Real-time data; 1981-84 data

**Nighttime Zonal Bias: AVHRR - In Situ**

- AVHRR
- Pathfinder
- - In Situ

- AVHRR
- Operational
- - In Situ

- 90N

- 90S

- 90S

- 90N

- '82

- '05

## Weekly & Daily OIDecember 1991

**Weekly & Daily OI****December 1991**

**Both OIs have bias correction for AVHRR data**
**Daily OI uses Pathfinder**
**Weekly OI uses Operational**** **
**From the figure note:**
- Operational data problem along 35oS
- Delayed mode processing allows data correction
- Daily scales reduced in high gradient areas

## Weekly & Daily OIJanuary 1998

**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 1998**

## OI Anomalies with Bias CorrectionJanuary 1988: Along equator

**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: 155oW, 140oW & 125oW
- OI bias correction fails to correct AVHRR Pathfinder satellite biases

## OI Anomalies with Bias CorrectionJanuary 1988: Along equator

**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: 155oW, 140oW & 125oW
- OI bias correction fails to correct AVHRR Pathfinder satellite biases
**Empirical Orthogonal Teleconnections (EOT) bias correction better at correcting biases**

## Daily Bias Differences: 1 Jan '03 - 31 Dec '04

**Daily Bias Differences: 1 Jan '03 - 31 Dec '04**

**EOTs reduce biases; Some residuals remain**

## 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 45-60 day time period would work

## 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°S

- 60°N

## 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

## Daily OI SST AnomaliesEOT satellite bias correction 

**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

**Left:****	****Pathfinder AVHRR OI **
**Right:**** Pathfinder AVHRR + AMSR-E OI**

## Daily FTP OI Products

**AVHRR only**
- Pathfinder  	(Jan '85 - Dec '05)
- Operational  	(Jan '06 - present)

**AVHRR + AMSR-E  **
- Pathfinder  	(Jun '02 - Dec '05)
- Operational  	(Jan '06 - present)
- AMSR-E 		(Jun '02 - present)

**Test other data: TMI, ATSR, MODIS...**