CCl/CLIVAR/JCOMM ETCCDI WorkshopCCl/CLIVAR/JCOMM ETCCDI WorkshopDe Bilt 13-15 May 2008De Bilt 13-15 May 2008

Climate Indices from Marine DataClimate Indices from Marine Data

Val Swail - Environment Canada, TorontoScott Woodruff - NOAA Earth System Research Laboratory, Boulder

Elizabeth Kent - National Oceanography Centre, SouthamptonDavid Parker - Met Office, Exeter

CLIMAR-III:CLIMAR-III:Third JCOMM Workshop on Advances in Third JCOMM Workshop on Advances in

Marine ClimatologyMarine Climatology6-9 May 2008, Gdynia, Poland6-9 May 2008, Gdynia, Poland

FOCI ANTICIPATED FOR MARINE FOCI ANTICIPATED FOR MARINE INDICESINDICES

• detection and attribution of climate changedetection and attribution of climate change• impact on marine industries (fishing, shipping, oil impact on marine industries (fishing, shipping, oil

and gas production, tourism)and gas production, tourism)• sea-level changesea-level change• marine hazards (extreme winds and waves, marine hazards (extreme winds and waves,

harmful algal blooms, pollution)harmful algal blooms, pollution)• changes in hydrological cyclechanges in hydrological cycle• changes in ocean circulationchanges in ocean circulation• changes in sea ice and ice bergschanges in sea ice and ice bergs• effects on coastal communitieseffects on coastal communities• ocean acidificationocean acidification

QUESTIONS Posed to CLIMAR-QUESTIONS Posed to CLIMAR-IIIIII

What observational data are needed (available) for climate change What observational data are needed (available) for climate change detection and attribution? detection and attribution?

What analyses of these data can provide information useful for climate What analyses of these data can provide information useful for climate change detection and attribution? change detection and attribution?

What international coordination on data issues would improve climate What international coordination on data issues would improve climate change detection and attribution?change detection and attribution?

What are the indices with most impact?What are the indices with most impact?

What indices should we include on version 1 of our list for marine indices?What indices should we include on version 1 of our list for marine indices?

How can we use what we have learned about data set uncertainties for How can we use what we have learned about data set uncertainties for indices?indices?

How do we make indices available to users? Common web site such as How do we make indices available to users? Common web site such as ETCCDI or links to that site?ETCCDI or links to that site?

How do we develop indices for inclusion in IPCC AR5 in 2013 with increased How do we develop indices for inclusion in IPCC AR5 in 2013 with increased focus on extremes and regional aspects?focus on extremes and regional aspects?

What other products should we consider for marine climatology?What other products should we consider for marine climatology?

CHARACTERISTICS REQUIRED FROM CHARACTERISTICS REQUIRED FROM INDICESINDICES• Indices should cover a range of Indices should cover a range of time and space scalestime and space scales, multi-decadal to , multi-decadal to

daily, global to regional and be relevant to their target audience daily, global to regional and be relevant to their target audience

• Indices should represent importantIndices should represent important impact-relevant impact-relevant aspects of the aspects of the climate system and where possible climate system and where possible link to the IPCClink to the IPCC..

• It must be possible to calculate and update the indices It must be possible to calculate and update the indices from existing from existing datadata..

• The indices must be prioritized due to The indices must be prioritized due to limits in capacity.limits in capacity.

• Indices can Indices can synthesize information and reduce noisesynthesize information and reduce noise by combining by combining different components of the climate system.different components of the climate system.

• Indices should be based on Indices should be based on homogenized homogenized and quality controlled and quality controlled datasets, well-understood models or reanalyses, or reliable predictions.datasets, well-understood models or reanalyses, or reliable predictions.

• Indices should have a Indices should have a good signal to noise ratiogood signal to noise ratio..

• A subset of indices should be suitable for A subset of indices should be suitable for presentation to politicianspresentation to politicians

• Common climate indicesCommon climate indices should be developed for models and should be developed for models and observationsobservations

• Indices should be robust for detection, important and Indices should be robust for detection, important and doabledoable

MARINE DATA SOURCES AND MARINE DATA SOURCES AND PROGRAMSPROGRAMS• ICOADS – ships (from 1662), moored and drifting buoysICOADS – ships (from 1662), moored and drifting buoys

• World Ocean Database (WOD)World Ocean Database (WOD)• Global Digital Sea Ice Data Global Digital Sea Ice Data BankBank (GDSIDB) (GDSIDB) • Permanent Service for Mean Sea Level (PSMSL)Permanent Service for Mean Sea Level (PSMSL)• Derived data sets – HadISST, HadSLP, HadGOA (Derived data sets – HadISST, HadSLP, HadGOA (www.hadobs.orgwww.hadobs.org ) )• Satellite – SST, wind, wave, ice, sea levelSatellite – SST, wind, wave, ice, sea level• ReanalysesReanalyses

• Shipboard Automated Meteorological and Oceanographic System Shipboard Automated Meteorological and Oceanographic System Initiative Initiative

• Global Ocean Surface Underway Data Pilot Project Global Ocean Surface Underway Data Pilot Project • Ship Observations TeamShip Observations Team• Data Buoy Cooperation PanelData Buoy Cooperation Panel• ArgoArgo• Ocean SitesOcean Sites• Global Sea Level Observing System Global Sea Level Observing System • International Ocean Carbon Coordination ProjectInternational Ocean Carbon Coordination Project• Global Temperature and Salinity Profile ProgramGlobal Temperature and Salinity Profile Program• JCOMMOPS (JCOMMOPS (www.jcommops.orgwww.jcommops.org ) )

Annual numbers of marine reports in ICOADS, stratified by platform type for 1936 to 2005

(Woodruff et al. 2008)

The potential for marine indices

Operational Resources required

Research required

Data required

Large scale pressure (e.g. NAO, PNA)

Temperature indices Atlantic Meridional Circulation

Max & min temperatures

Large scale temperature (e.g ENSO)

Marine winds and pressures

Currents Wind gusts

Sea Ice parameters Waves Polar lows. Storm surges

Ocean heat content Sea level Hydrographic time series (e.g. ICES)

Extremes

Salinity measures Fisheries information & biology

Precipitation

Ocean transports and water mass properties

Ocean chemistry (e.g. dissolved oxygen)

Ph/Ocean Acidification

Hurricanes

Clouds, humidity.

“Operational” Marine Indices

• Large Scale Pressure Indices• Calculated by many different groups.• Selection available from Ocean Observing Panel for

Climate (OOPC) website.• Link to existing sources

• Large Scale Temperatures Indices• Global mean temperature.• Gridded temperature anomalies.• Long term datasets, back to 1850• Available from www.hadobs.org• El Nino (e.g. Nino 3.4 Temperatures), link to OOPC

website• Sea Ice

• E.g. global scale ice extent; regional ice extents• Available from JCOMM Expert Team on Sea Ice or US

National Snow and Ice Data Center.

OOPC State of the Ocean

Multivariate ENSO Index Multivariate ENSO Index (MEI)(MEI)

• Based on the six main observed variables over the tropical Pacific: Based on the six main observed variables over the tropical Pacific: sea-level pressure, zonal and meridional surface wind, surface air sea-level pressure, zonal and meridional surface wind, surface air and sea temperature and total cloudiness fraction, in ICOADSand sea temperature and total cloudiness fraction, in ICOADS. .

• MEI is calculated as the first unrotated Principal Component (PC) of MEI is calculated as the first unrotated Principal Component (PC) of all six observed fields combined. Negative values of the MEI all six observed fields combined. Negative values of the MEI represent the cold ENSO phase, La Niña, while positive MEI values represent the cold ENSO phase, La Niña, while positive MEI values represent the warm ENSO phase (El Niño). represent the warm ENSO phase (El Niño).

• http://www.cdc.noaa.gov/people/klaus.wolter/MEI/http://www.cdc.noaa.gov/people/klaus.wolter/MEI/

13Hadley Centre for Climate Prediction and Research

Global temperature

Annual Anomalies and uncertainties

1850-2005

Monthly anomalies: 1850 – Jul 2006

Temperature trend over 1901-2003

15Hadley Centre for Climate Prediction and Research

Monthly Surface Temperature Sept. 2006

PercentilesAnomalies

Tropical Central and EastPacific SST Anomalies, 1850-2005

Trends in warm days 1950-2003

Blue and red dots indicate trends significant at the 5% confidence level. Crosses denote non-significant trends.

Days with tmax > 90th percentile

days / 54 yrs10 30 50-50 -30 -10

17Hadley Centre for Climate Prediction and Research

Annual sea-ice extent changes, 1973-2006 (updated from IPCC, 2001)

Retreating until late1990s.

Little retreat 1998-2003

2006 record low so far

Antarctic sea-ice

Not declining since 1976

Arctic sea ice

© Crown copyright

Background: ocean heat uptake

Lyman et al., [2006]

Heat content for Anomaly for the upper 300m

See Gregory et al. [2004]

To address these questions werequire:

(i) Comprehensive error estimates for observed time series.

(ii) Ocean climate indices with a high signal-to-noise ratio and small uncertainties.

Questions:

(i) What is the rate of oceanic heat uptake? (trend?)

(ii) Is the decadal variability seen in the observations (but not the models) real?

Marine Indices Requiring Resources

• Temperature - air and sea – mean & percentiles• Humidity – mean or median• Cloud cover- mean• Wind and wave

• mean, max, from observations• 10 and 90 percentiles, frequency greater than

percentile thresholds (absolute values – gale and storm winds; 3 and 6 m waves?); sea and swell? From reanalysis or satellites?

• Sea Level - mean global and regional anomalies• Storm Surge, Storm Tide, frequency, extreme• Sub-surface ocean

• Salinity - surface salinity• Temperature – isotherm depth (which?)• heat content anomaly (to 300m)• water mass properties (volume of 18˚ water?)

Global Wave Climatology AtlasS. Caires, G. Komen, A. Sterl, V. Swail

www.knmi.nl/waveatlas

Num

ber

of g

ridpo

ints

Year of changepoint

Monthly mean wind speed

1966

Monthly mean sig. wave height

Num

ber

of g

ridpo

ints

Year of changepoint

1966

Number of gridpoints of a significant changepoint in the indicated year

Wind speed – locations of changepoint in Nov. 1966 Sig. wave height – location of changepoint in Nov. 1966

Grid-boxes of significant changepoint are shown in black

xx

Monthly mean wind speed (m/s) at (40.5°N, 40.5°W)

Nov. 1966 Dec. 1997

Monthly mean sig. wave height (m) at (40.5°N, 40.5°W)

Nov. 1966 Dec. 1997

GLOSS NetworkGLOSS NetworkSea level, storm surge indicesSea level, storm surge indices

http://www.cdc.noaa.gov/coads-las/servlets/dataset

© Crown copyright

Eighteen Degree Water (subtropical mode water (STMW)) volume in the North Atlantic

(defined as volume of water with temperature between18.5 C and 17.5 C in the subtropical North Atlantic).

Correlated with the NAO at lag 6 yrs (NAO leads the EDW) r=0.36 for ‘winter’ (Feb, Mar, Apr) after Kwon & Riser, 2004

Source: HadGOA

HadGOA: monitoring water masses

CO2 Uptake (Bates et al).

© Crown copyright

Changes in mean T and isotherm depths

Mean 14C isotherm depth

Mean T above 14C isotherm

1985-2004 minus 1961-1980

Deepening of isotherms in N. Atlantic associated with

change in phase of NAO.

Large areas of slight shoaling and smaller areas of large deepening

Wide-spread warming signal.

Less prone to aliasing from changes in ocean circulation than z-levels.

Greater insight into underlying physical mechanisms

More Speculative Marine Indices

• Temperature - min, max and higher percentiles

• Wind and wave - higher percentiles and extremes

• Measures of persistence

• Storm Surge inundation zones

• Sea Ice – ice thickness and stages of development; iceberg propagation

• Currents

• Biological – Harmful Algal Blooms, coral bleaching

• Atlantic Meridional Overturning Circulation

Enabling Enabling MechanismsMechanismsICOADS ICOADS - Critical and critically under-resourced- Critical and critically under-resourced

Proposed new initiative for value-added ICOADS (QC, bias Proposed new initiative for value-added ICOADS (QC, bias corrections, etc.)corrections, etc.)

JCOMM Expert Teams JCOMM Expert Teams Wind Waves and Storm SurgesWind Waves and Storm SurgesSea IceSea IceMarine ClimatologyMarine Climatology

Task Team on the Marine-meteorological and Task Team on the Marine-meteorological and Oceanographic Summaries (TT-MOCS)Oceanographic Summaries (TT-MOCS)

Task Team on Delayed-Mode VOS (TT-DMVOS)Task Team on Delayed-Mode VOS (TT-DMVOS)

Engage expertise within the CLIMAR community to assist in the Engage expertise within the CLIMAR community to assist in the development and production of marine indices(development and production of marine indices(marineclimatology.netmarineclimatology.net))

Liaise with other groups interested in marine indices such as the AOPC Liaise with other groups interested in marine indices such as the AOPC and OOPCand OOPC

The End!