Forecasting Ocean Atmospheric Model (FOAM)
Parent Body: The Met Office, London Road, Bracknell, Berkshire, RG12 2SZ

Principal Functions
Short period ocean analysis and forecasting.

General Details
FOAM produces real-time analyses and forecasts of the temperature, salinity and currents of the deep ocean for up to five days ahead. FOAM is built around a physically based ocean model. It is driven by surface fluxes from the Met Office's global Numerical Weather Prediction (NWP) model and assimilates measurements of ocean temperature (e.g. from expendable bathythermographs (XBTs) and conductivity/temperature/depth (CTD) sensors or profiling floats); ship, buoy and satellite (AVHRR) sea-surface temperature (SST) reports; together with data from the TOGA TAO array. A global version of FOAM with one-degree horizontal resolution and 20 levels in the vertical has been run every day in the operational suite at The Met. Office since October 1997. 

Specification
The present operational version of global FOAM has a uniform latitude-longitude grid with one-degree resolution. There are 20 unequally spaced levels in the vertical with highest resolution (10m in the top four layers) in the upper 200m and decreasing to layer thicknesses of 600m in the deep ocean. This version of FOAM was designed to produce forecasts of the large scale temperatures for the global ocean for up to a week ahead. With its relatively coarse horizontal resolution it cannot represent the fronts and eddies in the ocean. However, it does allow the large-scale changes in upper ocean structure due to meteorological forcing and large-scale ocean processes to be analysed and forecast.

Future Plans
The FOAM system is being improved so that it can analyse and predict meso-scale eddy features. To achieve this we are developing a set of nested relocatable high-resolution ocean models. As a first step towards this a suite of three models has been set up. This consists of the 1° global model, a 1/3° Atlantic and Arctic model which takes its boundary conditions from the 1° model, and a 1/9° model which takes its boundary conditions from the 1/3° model. The 1/3° Atlantic/Arctic model is planned to be implemented operationally in 2001. The first area chosen for the 1/9° model covers the Gulf of Mexico, Caribbean and part of the Atlantic off the north Brazil coast. This area was chosen because it contains the main meso-scale ocean features (eddies and fronts) which can be resolved by the 1/9° model, some of which can also be resolved by the 1/3° model. It is also an area of commercial interest for the oil industry, and as a result its physical oceanography has been widely studied and documented. In the future we also plan to set up a 1/9° model for the north-east Atlantic.

Availability
Model data from global FOAM are now available to the wider oceanographic community via the internet using our Data and Products Distribution Service (DPDS). FOAM data and products are available 'free of charge' to the research and education community for non-commercial use; for commercial use a small charge for the information will be made. For specific details on how to receive FOAM data please see: http://www.metoffice.gov.uk/research/ocean/operational/dpds/dpds_foam.html

Further Information
For further information on FOAM, our other ocean modelling capabilities supporting operational oceanography, seasonal forecasting and climate prediction, and the availability of ocean model data and products see Ocean Applications.

Contact Information
Jon Turton
Ocean Applications
The Met Office
London Road
Bracknell
Berkshire RG12 2SZ
Telephone:  01344 856478
Fax:  01344 854499
email:  jdturton@meto.gov.uk