# Presentation: 742198

## Summary of Progress Since MARCDAT-I and CLIMAR-II

- Elizabeth Kent, National Oceanography Centre, Southampton,  UK
- with help from
- David Berry,  Mark Bourassa, Ken Casey, Gil Compo, Sergey Gulev, David Parker, Nick Rayner, Dick Reynolds, Shawn Smith, Tom Smith, Val Swail,  Dennis Wheeler,Scott Woodruff, and Takashi Yoshida

## Outline

- The Recommendations
- Progress Highlights
- Data Recovery and Improvement
- Dataset Development
- Metadata
- Data Archival and Access
- Wider Interactions
- Remaining Challenges

## The Recommendations

- Both MARCDAT-I in Jan/Feb 2002 and CLIMAR-II in November 2003 made recommendations for specific tasks required to advance marine climatology
-  A website was set up and progress towards meeting the recommendations was monitored
- _[http://www.cdc.noaa.gov/coads/climar2/recs.html](http://www.cdc.noaa.gov/coads/climar2/recs.html)_
- Some areas show very good progress (e.g. SST,  surface pressure,  data availability and metadata)
- Others show more work is needed (e.g. winds,  waves and data homogenisation)

## The Recommendations

- Available as a handout,  6 sections
- MARCDAT-I, Jan/Feb 2002
- A:  SST and Surface Temperature
- B: Surface Pressure and Wind
- C: Technical Issues
- CLIMAR-II, November 2003
- D: Climate Monitoring
- E: Metadata and Homogenisation
- F: Uncertainties, Data Availability and Future Workshops

## Progress Highlights: Data Recovery

- The digitisation of historical data has improved our knowledge of long term climate change (Recs B9, C1)
- Kobe Collection
- CLIWOC (1750 - 1850, Talk: Wheeler)
- NOAA Climate Database Modernisation Programme (CDMP, Talk: Elms)
- EMULATE
- These data must then be incorporated into ICOADS, a complex and expensive task (Talk: Woodruff, Worley and Reynolds)

## Significance of the digitized Kobe Collection Increase of available data in the Pacific 

- Available data in the Pacific in the early 20th century significantly increased by both of the Kobe digitisation projects.

*Courtesy of Takashi Yoshida, JMA*

## Historical Data Digitisation:  CLIWOC

*Courtesy of Dennis Wheeler, University of Sunderland, UK*

-  CLIWOC focussed on data from 1750-1850
-  Only 5% of UK data were digitised
-  Data digitised were for local noon
-   A multi-lingual dictionary of terms was      	developed
-  Work underway to incorporate into 	ICOADS

- (red = English data; purple = Spanish; blue = Dutch

- Blue =English
- Red = Spanish
- Black = French
- Yellow = Dutch

## Progress: Data Recovery and Improvement

- Initiatives to include research quality meteorological measurements in ICOADS (R: C7)
- Collaborative project between FSU Research Vessel Surface Meteorological Data Center and ICOADS  (Talk by Smith,  Woodruff and Worley)
- Retrieval of humidity observations only available as relative humidity (R: F5)
- In progress, necessary for e.g.TAO moorings and some Research Vessels
- Initiatives to improve *in situ* data quality
- SAMOS (poster by Smith)
- VOSClim (R: E6,   talk by Kent, North, Woodruff and Berry)
- And we now have Pathfinder AVHRR satellite surface temperature data for lakes and inland seas (R: A7)

- Pathfinder V5 now contains temperatures for  inland lakes and waters... but they need to be validated and properly quality controlled!

*Courtesy of Ken Casey,  **NOAA National Oceanographic Data Center*

**Notes:**
Pathfinder V5 now contains inland lakes and waters... but they need to be validated and properly quality controlled!

## Progress: Dataset Development

- Improved Methods for Dataset Construction
- Many marine meteorological datasets,  now contain uncertainty estimates (A14,15, B14) e.g.
- ERSST.v2,  HadISST,  HadMAT and HadSLP, EMULATE
- A variety of techniques are being used, e.g.
- Optimal techniques (Posters: Kaplan; Yoshikawa, et al.. Talk: Bourassa and Smith)
- Daily data (e.g. EMULATE, Talks: Reynolds, Casey and Smith,  Posters: Sakurai, Kurihara and Kurango and Kent and Berry)
- Blending of datasets (Talks: Casey, Barton, Kearns and Reynolds, Poster: Smolyanitsky)
- Reanalysis (Talks: Compo, Whitaker and Sardeshmukh and Simmonds)

## Progress: Dataset Development

- A wider variety of variables are being analysed, e.g.
- Waves (Poster:  Grigorieva and Gulev)
- Winds (Talk: Thomas, Kent and Swail)
- Air Temperature (Poster: Rigor, Stern and Schweiger)
- Surface Fluxes (Talk: Gulev and Belyaev; Poster: Kent and Berry)
- Clouds (Talk:  Warren and Hahn)
- Subsurface (Posters: Palmer, Ansell and Tett;  Harrison and Carson)
- Sea Ice (Talk: Fetterer, Fowler, Arbetter, Meier and Street, Poster: Smolyanitsky)

## Improved Methods for Dataset Construction

- Tropospheric reanalysis using only surface pressure inputs (R: B13)
- (See talk by Compo, Whitaker and Sardeshmukh)

- Monthly fields from daily optimal interpolation of ICOADS data,  in this case air temperature.
- (See poster by Kent and Berry)

- Global (land and ocean) surface temperature reconstruction, includes 95% confidence intervals
- Smith and Reynolds (2005) "A Global Merged Land-Air-Sea Surface Temperature Reconstruction Based on Historical Observations (1880-1997)", J. Climate

- Total sampling errors in net air-sea heat flux.
- Gulev, Jung and Ruprecht, "Estimation of the Impact of Sampling Errors in the VOS Observations on Air-Sea Fluxes" J. Climate, submitted

## Improved Methods for Dataset Construction

- JMA Merged Global Daily SST Dataset
- See talk by Sakurai, Kurihara and Kurango

- Gradient of AMSR-E SST, Daily, Jan-Mar 2003
- See talk by Smith, Reynolds, Casey and Chelton.

- Indian Ocean Latent Heat Fluxes from FSU

## Progress: Understanding of bias

- Improved understanding of data biases (R: A1, A3, B5, B8, E5), for example:
- SST (Talks: Kennedy; Reynolds, Casey and Smith, Poster: Sakurai, Kurihara and Kuragano)
- Air Temperature (Talk: Berry and Kent)
- Humidity (Poster: Willett, Jones, Thorne and Gillett)
- Winds (Posters: Lindau; Moat, Yelland, Kent and Molland,  Talk: Thomas, Kent and Swail)
- Waves (Poster: Grigorieva and Gulev)
- Clouds (Talk: Warren and Hahn)
- Ocean profiles (Poster: Ingleby)
- Fluxes (Poster: Bourassa)

## Uncertainties in bias corrections

- © Crown copyright

- Proportion of canvas buckets and speed of ships increase over time, leading to increased corrections

- Inclusion of U.S. Merchant Marine

- 1000 realisations of bucket corrections are generated by varying inputs within bounds defined by their uncertainties

- Larger corrections than before

**Notes:**
We have found that we have to adjust the Folland and Parker (1995) corrections to fit the new data base. The red curve is the global average of the correction fields applied to HadSST2. We find that we require smaller corrections at the start of the record than before. More significantly, we need greatly reduced corrections between 1939 and 1941 to allow for the inclusion of the newly digitised and now dominant U.S. Merchant Marine data at this time. These data are largely measured using engine cooling water which produces warmer measurements than the previously dominant canvas bucket collected data.

Recalculating the bias corrections has also allowed us to assess their uncertainty. Remembering that they are created by combining three pieces of information: ships’ speeds; proportions of canvas and wooden buckets and quantities of heat lost from these buckets we can generate multiple realisations of the corrections by varying these input parameters within their own likely ranges. The 95 percent confidence interval is shown here by the shaded area. The uncertainty increases as the corrections increase.

## How has the recovered SST data changed the uncertainty?

- Addition of new data sources reduces sampling uncertainty

- June 1940 - old

- June 1940 - new

**°C**

**°C**

- © Crown copyright

**Notes:**
Can we quantify what effect the additional data have had on our uncertainty estimates? Repeating the calculation of sampling and measurement uncertainty for the new and old data bases, we see that the additional data have reduced the estimated errors, as expected. The additional data have populated the Atlantic in June 1940, allowing us more accurate estimates of SST anomaly there. Globally, the square root of the mean squared sampling and measurement error is significantly reduced at times when additional data have had most impact on data coverage.

## Progress: Metadata

- Metadata for the Voluntary Observing Ships are now more accessible
- WMO Publication No. 47 Metadata now served alongside individual ICOADS reports
- Pub. 47 metadata for 1955 to 1972 being digitised by CDMP (available hopefully this year)
- WMO now only 9 months behind in metadata delivery!
- Observing practice literature is being archived and digitised
- Metadatabase for Offshore Data Acquisition Systems (ODAS) set up by JCOMM and being populated
- Challenge for climate is to find resources to fill this important database with historical ODAS metadata

## Metadata Digitisation - CDMP

- This Voluntary Observing Ship metadata from 1955 has already been imaged and will shortly be digitised

## Progress: Metadata

- Improved understanding of the importance of metadata
- Metadata are as important as the data,  and are essential if we are to quantify and remove bias
- We can use metadata from a variety of sources
- WMO Publication No. 47 for VOS
- ODAS Metadatabase for buoys and platforms
- Observing and coding instructions (Poster: Yoshida)
- Questionnaires (Russian SHIPMET and WMO)
- Historical descriptions of observing practice

## Progress:  Data Archival and Access

- Data Archival
- New International Marine Meteorological Archive (IMMA) data format
- "Attachments" can flexibly add important information for particular data sources, e.g.
- VOS metadata are served alongside data in attachment
- Data Access
- NetCDF emerging as preferred exchange format for data products?
- Frameworks such as OPeNDAP allow for easy intercomparison of datasets
- Data access is typically free and open, (R: C5)
- Many more datasets available in near real time (R: B1, C2, E1)

## Progress: Wider Interactions

- The CLIMAR and MARCDAT Workshops facilitate the collaborative efforts required to advance marine climatology
- CLIMAR-II Special Issue of the International Journal of Climatology effective way of rapidly disseminating results
- JCOMM-II
- recommended that CLIMAR-III go ahead as a self-funding workshop in 2007
- recognised the importance of marine climatology and enhanced mandate of their Expert Team on Marine Climatology

## Progress: Wider Interactions

- Attendees at the workshops are members of a wide range of international panels and groups including:
- AOPC,  OOPC
- WCRP (JSC, WOAP, WGSF)
- JCOMM (ETMC, ETWS, ETSI, ETDMP, SPA, OPA, SOT)
- IPCC Working groups
- Are we (and they) making the best use of any links? (R: D2)

## Remaining Challenges

- CLIMAR-II called for marine observations to be collected following the GCOS Climate Monitoring Principles (R: D1)
- This was endorsed by JCOMM-II last month
*The Commission also acknowledged that continuity in the observing system was of central importance for climate applications, accepted the GCOS Climate Monitoring Principles as best practice, and noted that the work of the Data Buoy Co-operation Panel (DBCP), Ship Observations Team (SOT, inc. VOS, SOOP and ASAP), and the Global Sea Level Observing System Group of Experts (GLOSS GE) would be conducted in accordance with the GCOS Climate Monitoring Principles wherever possible*
- However ...

## Sources of In Situ data in ICOADS

- VOS data in decline

*From Worley et al. (2005), International Journal of Climatology*

## Change in Data Uncertainty with Time

*From Kent et al. (2005), Poster at JCOMM-II,  available from **http://www.noc.soton.ac.uk/JRD/MET/PDF/JCOMM2.pdf*

**Blue:  adequate data coverage;  Red: inadequate data coverage**

**SST**

**Air **
**Temperature**

## Remaining Challenges (1)

- Regular intercomparisons of analyses (R: A13)
- Winds (R: B4-7, B14)
- Talk by Thomas et al. will show problems with the recent VOS visual winds.
- TurboWin height correction, 2002 - 2004+
- Quality Control (R: C4)
- ICOADS trimming limits approach needs improving
- Climate Monitoring
- VOS observations in decline and changing in character (R: D1, D2)
- Accuracy requirements for gridded fields not defined (R: D4)
- Climate indices required (R: D6)

## Remaining Challenges (2)

- Standards for instrument design and positioning (R: D5)
- Wave information
- need for spectral wave measurements in Southern Ocean (R: D7)
- and wave information in ICOADS summaries (R: D8)
- Metadata
- Historical buoy (ODAS) metadatabase requires filling (R: B10, E4)
- WMO still struggling to supply Pub. 47 in timely manner (R: E1)
- Some ship operators not keeping Pub. 47 entries up to date
- Overhaul of operational Pub. 47 to produce climate metadatabase
- Do we need a working group on uncertainties? (R: F1)
- Definitive website with links to data sources and data products (with JCOMM, R: F2, F6)

## Remaining Challenges (3)

- Data products
- Work with JCOMM on data products?
- Need to bring together ocean/ice/surface met. data?
- How do we use high-quality non-climate products such as those from GODAE?
- What resolution data do we actually require - can we resolve the diurnal cycle?