Met Office Stratospheric Analyses - New Dynamics The assimilation system that produces the Met Office stratospheric data will soon be changed to use the New Dynamics (ND) version of the Unified Model. The changeover is scheduled for 28th October 2003. **Users of the data need to be aware of the following points:** - The data will be ordered from South to North, instead of North to South. - As before, the wind components (u and v) will be produced on a grid that is staggered relative to the mass grid (used for T and z). The output fields use the "Arakawa B grid" staggering, as before, even though the ND model uses a "C grid" staggering. - The vertical velocity will be w (dz/dt), rather than omega (dP/dt), and will be output on the mass grid. - Three additional UARS levels will be output (25 instead of 22), up to 0.1 hPa (instead of 0.316 hPa). If you use the grid definitions in the PP header record, the changes to the ordering of the data will be transparent, otherwise you will need modify your programs to allow for those changes. Access routines are supplied by the Met Office to help users read the data files. The original versions were written to access data from the UARS CDHF, but recent versions also read PP format data, as supplied to the BADC. A revised version of the access routines has been written (version 5c - file name acsasm_v5c.f). This is very similar to the previous version (5b), except that it will recognize the new w fields (as well as omega), and the default settings for field types and number of levels have been modified for New Dynamics. VAX/VMS-specific code (only a few lines) has been deleted. At the BADC, the new data files can be found in the current year assimilated data directory: /badc/ukmo-assim/data/standard/2003/ The associated documentation, as provided by the Met Office is available in the assimilated data doc directory: /badc/ukmo-assim/doc/ieee_binary/new_dynamics/ The Assimilated data documentation on the BADC Web pages will be updated shortly. BADC Support 28th October 2003

The Berlin Stratospheric data series now available from BADC ============================================================ The Berlin stratospheric data series contains temperature and geopotential height data on the 100, 50, 30, 10 mb pressure surfaces produced at the Meteorological Institute, Free University of Berlin, from radiosonde data and rocket observations. The data covers the northern hemisphere during the years 1957 to 2001 and is available on both a 10° x 10° and 5° x 5° grid. More information available at BADC Team 23/10/2003

Due to an electricity supply shutdown at Rutherford Appleton Laboratory (18-19th October 2003), the BADC File server will be consequently temporarily shutdown **from Friday 17th October at 3pm to Sunday 19th October**. The BADC file server is expected to be back online from Monday 20th October. This shutdown unfortunately implies that the BADC Web site and access to data and services will be temporarily unavailable. We are sorry for the inconvenience this may cause. BADC Support 16/10/03.

The BADC help pages now includes a description and tutorial of two software packages used extensively in the atmospheric sciences: * **CDAT** - see * **GrADS** - see We have also made a GrADS/GRIB interface page which is relevant to all users of our datasets held in GRIB format. This is located at: Climate Data Analysis Tools (CDAT) is a freely available software infrastructure used for analysis, manipulation and plotting of atmospheric science (and other) data. It is designed for gridded datasets but can also cope with other types. Below are some key features of CDAT: * the software is open-source, consisting of a collection of Python modules. * available for multiple platforms (but not Windows). * a choice of interfaces: command-line, scripting or graphical user-interface (Visual CDAT (VCDAT)). * an XML-based format and tools for aggregating large datasets. * manipulation of large data arrays possible due to use of Python *Numeric* package. * interfaces to external packages such as the Live Access Server (LAS) for web-based access to datasets.< /LI> Grid Analysis and Display System (GrADS) is a freely available package used for analysis, manipulation and plotting of earth science data. It is designed for gridded datasets but can also cope with station data. Below are some key features of GrADS: * available for multiple platforms as an executable (including Windows). * accessible by both a command-line and scripting interface. * support for multiple common data formats. * significant support for user-defined plotting. * manipulation of large 4-D datasets. * a rich set of built-in functions for data manipulation. Ag Stephens, BADC, 11th September 2003

NASA satellite observations have provided the first evidence the rate of ozone depletion in the Earth’s upper atmosphere is decreasing. This may indicate the first stage of ozone layer recovery. ...

Update on BADC archive of ERA-40 data: 6-hourly data and monthly means ====================================================================== 1. The 6-hourly ERA-40 Re-analysis Dataset - is now complete. 2. The monthly means for the ERA-40 Re-analysis Dataset - are now available (Includes a special note about INCORRECT FILES during the extraction period). More details follow: ========================================== 1. The 6-hourly ERA-40 Re-analysis Dataset ========================================== The 6-hourly data for the ERA-40 dataset is NOW COMPLETE in the main BADC archive from 1958-2001. Details about the type of data available can be found at: and the links from that page. A parameters page provides a list of those available on each level type: ======================================================= 2. The monthly means for the ERA-40 Re-analysis Dataset ======================================================= Two types of monthly mean are now available for the ERA-40 dataset. These are the: i. Monthly diurnal means (moda) - calculated from all time steps in a given month (i.e. one mean per month). ii. Monthly synoptic (6-hourly) means (mm) - calculated from all values of a given time of day in a given month (i.e. 4 means exist per month, at 00, 06, 12 and 18UTC). Details on these means are now available at: SPECIAL NOTE FOR USERS ACCESSING ERA-40 MEANS DURING THE EXTRACTION PERIOD: =========================================================================== Please note that during the extraction period (January - May 2003) some of the monthly mean files were incorrect. The means were not clearly visible and had not been advertised at this period so I am not aware of anyone having used them. However, if you did locate the means and you have used those located under one of the following directories then please obtain the new means as directed in the link above. The directories where errors occurred were /badc/ecmwf-e40/data/diags, /disks/tornado4/e40_means/mm and /disks/tornado4/e40_moda/moda. All the erroneous means were deleted on 20th June 2003. BADC Support 03/07/03.

Temporary Disruption to BADC services on Monday 30th June 2003 ============================================================== The BADC file server, Tornado, has experienced a hardware fault earlier this morning. The fault appears to have been cleared after reseating the controllers. An engineer is still expected later today and we may need to take the machine down for him to investigate the fault. We are sorry for the inconvenience this may cause. BADC Support 30/06/03.

TRAJECTORY WEB SERVICE IS BACK ONLINE =========================================== The BADC Trajectory is now back in service at: BADC Support 26/06/03.

TRAJECTORY WEB SERVICE TEMPORARILY UNAVAILABLE =================================================== We regret that the BADC trajectory service is not currently available due to a technical problem. We hope to have it fixed shortly. Sorry for any inconvenience. BADC Support 20/06/03.