# Presentation: 289240

## Global Ocean in 2006-2007

- Prepared by
- Climate Prediction Center, NCEP
**February 8, 2008**

- _[http://](http://www.cpc.ncep.noaa.gov/products/GODAS/)__[www.cpc.ncep.noaa.gov](http://www.cpc.ncep.noaa.gov/products/GODAS/)__[/products/GODAS/](http://www.cpc.ncep.noaa.gov/products/GODAS/)_

## Overview

**Above normal global mean SSTs anomalies continued their long term trend**
**However, global mean SST anomalies decreased from their 2006 level**
**The decline occurred in almost all the ocean basins (except the Indian Ocean)**
**Global mean sea surface height anomaly increased 68% from 2006 to 2007**
**Pacific Ocean**
**El Niño conditions decayed rapidly at the beginning of the year and gave way to moderate-strength La Niña (ONI SST < -1C) SSTs by the fall of 2007**
**MJO-related winds had substantial impacts on ocean heat content, and appear contributed significantly to the demise of 2006 El Nino **
**North Pacific SST near Gulf of Alaska decreased to below-normal in 2007 from near-normal in 2006**
**Indian Ocean**
**Above normal SST anomalies continued in the Indian Ocean**
**A brief IOD episode during SON 2007 (unexpected during a La Niña episode)**
**Atlantic Ocean**
**Above normal, but weaker, SST anomalies**
**SST anomalies in the Main Development Region continued their decline from 2005**
**North Atlantic continued to be above normal (but weaker than in 2006)**

_**Overview**_

## Data Sources

**  ****Optimal Interpolation SST (OI SST) version 2 **
**  ****Reconstructed SST (ERSST) version 3 **
**  ****NCEP/NCAR Reanalysis-1 850 mb winds, 200mb velocity potential, heat fluxes**
**  ****NOAA’s Outgoing Long Wave Radiation**
**  ****CPC’s CAMS-OPI precipitation**
**  ****NCEP’s Global Ocean Data Assimilation System (GODAS) subsurface temperature, heat content, tropical cyclone heat potential**
**  ****Aviso Altimetry Sea Surface Height**
**  ****Ocean Surface Current Analyses – Realtime (OSCAR)**

## Global SST Anomaly (0C) and Anomaly Tendency

_**Global SST Anomaly (**__**0**__**C) and Anomaly Tendency**_

** ****Horseshoe SST in tropical Pacific dominated by 2007 La Nina**
**- Weak above-normal SST in tropical Indian and Atlantic**
** ****Strong above-normal SST north of Bering Strait and high-latitude North Atlantic**
** ****Strong below-normal SST in Gulf of Alaska**
** ****Global mean SSTA is 0.13C, 0.1C lower than that of 2006**

** ****SST decreased in tropical Pacific, Southeast Pacific, North Pacific and North Atlantic**
** ****SST increased substantially north of Bering Strait**

** ****Weak above-normal SST in tropical Pacific dominated by 2006 El Nino**
** ****Weak above-normal SST in tropical Indian and Atlantic **
** ****Strong above-normal SST in high-latitude North Atlantic**
** ****Global mean SSTA 0.21C**

## Slide 5

## Equatorial Temperature Anomaly

_**Equatorial Temperature Anomaly**_

**  ****East-west dipoles in SSHA and SSTA dominated by 2007 La Nina**
**  ****No east-west dipoles in SSHA and SSTA due to atypical evolution of 2006 El Nino**

_**Tropical SST Anomaly**_

**La Nina**

**El Nino**

**IOD**

## NINO Indices

** ****Positive SSTA progressed from west to east during 2006 El Nino**
** ****2006 El Nino ended abruptly in February 2007**
** ****Negative SSTA progressed from east to west during 2007 La Nina**

_**IOD Indices**_

** ****SETIO transitioned from positive to negative in August 2006, leading to a 2006 IOD event**
** ****2006 IOD event decayed  in December 2006**
** ****Mini IOD in 2007**

## 2006 MJO Evolution

_**2006 MJO Evolution**_

**  ****Westerly Wind Burst (WWB) associated with MJO were active in Spring 2006, contributing to demise of “2005 La Nina” and onset of 2006 El Nino**
**  ****WWB moved progressively eastward along with positive SSTA in western-central Pacific**
**  ****MJO initiated in Indian Ocean in mid-December 2006 contributed to demise of 2006 El Nino**

**IOD**

**WWB**

**El Nino**

**onset**

**Notes:**
Have a single plot? Yes

## 2006 MJO’s Impacts on Ocean

_**2006 MJO’s Impacts on Ocean**_

**  ****MJO initiated in late-February 2006 produced downwelling Kelvin waves**
**  ****MJO initiated in April, June and September 2006 increased heat content in central-eastern Pacific**
**  ****MJO initiated in mid-December 2006 generated strong easterly wind burst, leading to depletion of heat content and demise of 2006 El Nino**

**IOD**

**WWB**

**Positive phase Kelvin wave**

**Negative phase Kelvin wave**

**El Nino**

**El Nino**

**IOD**

**Notes:**
Have a single plot? Yes

## 2007 MJO Evolution

_**2007 MJO Evolution**_

** ****WWB progressed westward  while warm SSTA in western Pacific moved westward **
**  ****MJO in November-December was the strongest in the past four years according to CPC’s MJO monitoring team**

**WWB**

**La Nina**

**onset**

**Notes:**
Have a single plot? Yes

## 2007 MJO’s Impacts on Ocean

_**2007 MJO’s Impacts on Ocean**_

**  ****MJO in December 2006 produced strong westward surface currents and negative heat content anomalies, leading to abrupt demise of 2006 El Nino**
** ****Stronger easterly anomalies associated with MJO in December 2007 produced upwelling Kelvin wave, leading to strengthening of current  La Nina**

**WWB**

**Positive phase Kelvin wave**

**Negative phase Kelvin wave**

**La Nina**

**La Nina**

**demise**

**onset**

**Notes:**
Have a single plot? Yes

## SST Anomaly in North Atlantic

_**SST Anomaly in North Atlantic**_

** ****SSTA in hurricane Main Development Region was near normal in JASON 2007, much cooler than that of 2006**
** ****High-latitude North Atlantic SSTA in 2007 were above-normal, but not as warm as those in 2006**
** ****North Atlantic SSTA were closely related to NAO index**

**MDR**

**MDR**

**MDR**

## North America Western Coastal Upwelling

** ****2007 upwelling season is close to normal**
** ****Negative PDO is associated with above-normal upwelling**

_**North**__** **__**America Western Coastal Upwelling**_

** ****Area below (above) black line indicates climatological upwelling (downwelling) season**
** ****Climatologically upwelling season progresses from March to July along the west coast of North America from 36****o****N to 57****o****N.**

- _[UW/NOAA JISAO PDO page ](http://jisao.washington.edu/pdo/)_

## Global Prec. Anomaly and Anomaly Tendency

**  ****Convection suppressed in central tropical Pacific, ITCZ, Brazil, Southeast Indian Ocean**
**  ****Convection enhanced in western tropical Pacific, SPCZ, Northern Indian and western coast of  Africa**

**  ****Enhanced convection reduced SW at surface**
**  ****Suppressed convection increased SW at surface**

## Global Net Heat Flux Anomaly and Anomaly Tendency

**  ****Net heat flux anomalies were dominated by LH+SH**
**  ****Net heat flux anomalies cooled Western Hemisphere Warm Pool, Northwest Atlantic and Southern subtropical Ocean**
** ****Net heat flux anomalies warmed North Indian, North Pacific and high-latitude Southern Ocean**
** ****Global mean NFLX is 3.15 W/m****2**** **
** ****Global mean NFLX anomaly is 0.1 W/m****2**

** ****Net heat flux changes warmed SST  in Gulf of Alaska, SPCZ and high-latitude Southern Ocean**
** ****Net heat flux changes cooled South Indian, central tropical Pacific**

## Global SSH Anomaly and Anomaly Tendency

**  ****East-west SSH dipole in tropical Pacific dominated by 2007 La Nina**
**  ****Strong above-normal SSH in western Indian Ocean**
**  ****Above-normal SSH in Southern Oceans**
**  ****Below-normal SSH in Gulf of Alaska**
**  ****Global mean SSHA is 1.9cm, increased by 68% from that of 2006**

**  ****SSH increased in subtropical Pacific, but decreased in tropical Pacific – heat discharge**
** ****SSH increased in tropical Indian**
** ****SSH increased in Southern Ocean **
** ****SSH increased in subtropical North Atlantic **

** ****East-west SSH dipole in tropical Indian dominated by 2006 IOD**
**  ****Above-normal SSH in western subtropical Pacific**
**  ****Above-normal SSH in Southern Oceans**
**  ****Below-normal SSH along eastern coast of North America**
**  ****Global mean SSHA is 1.1cm**

## Global Heat Content (0-750m) Anomaly and Anomaly Tendency

**  ****East-west HC dipole in tropical Pacific dominated by 2007 La Nina**
** ****Above-normal HC in southwestern Indian Ocean**
**  ****Below-normal HC in Gulf of Alaska**
**  ****Global mean HCA 8.6x10****7**** J/m****2**

**  ****HC increased in subtropical Pacific, but decreased in tropical Pacific – heat discharge**
**  ****HC increased in tropical Indian**
**  ****HC increased in Southern Ocean **
**  ****HC increased in subtropical North Atlantic **

**  ****Major features consistent with “State of the Climate in 2006”, BAMS 2007**
**  ****Global mean HCA -12x10****7**** J/m****2**

**Likely problematic due to lack of observations**

**Johnson, Lyman, Willis, BAMS 2007**

## SST Anomaly for Atlantic Hurricane in Jul-Nov 2007

_**SST Anomaly for Atlantic Hurricane in Jul-Nov 2007**_

**Tropical North Atlantic was cooler in 2007 than in 2006**
** ****Strong positive SSTA north of Bering Sea corresponds to 2007 Arctic sea ice minimum**

## Tropical Cyclone Heat Potential (TCHP) Anomaly for Atlantic Hurricane in Jul-Nov 2007

**  ****TCHP in Atlantic Main Development Region  was similar in 2007 and 2006, slightly above-normal.**

## 200-Mb Annual Mean Height Anomaly                

** ****Positive height anomalies consistent with the above normal global mean SSTs**
** ****However, tropical heights were lower than for 2006 possibly because of La Nina conditions in the tropical eastern Pacific**
** ****Role of SSTs?**

**200-Mb Annual Mean Height Anomaly                **

## Annual Mean Surface Temperature               

** ****Land average ~1.02 (warmest since 100; Ocean average~0.38 (9****th**** warmest since 1900) ...Source—NCDC)**
** ****Land 1.02****o****C (2007) vs. 0.77****o****C (2006)**
** ****Ocean 0.37****o****C (2007) vs. 0.45****o****C (2006)**

**Annual Mean Surface Temperature               **

## Comparison of Obs and Model Simulations Forced with SSTs               

**Comparison of Obs and Model Simulations Forced with SSTs               **

** ****For the annual mean, AGCMs were successful in simulating above normal heights and above normal land temperatures **

**Notes:**

Only Jan-Nov avergae for the models