Mesoscale Modelling

This section provides information specific to the mesoscale weather modelling community.

Mesoscale weather modelling support provides:

• UM start dumps from the Met Office,
• Ancillary file creation,
• Data visualization tools,
• Analysis tools for diagnostics, such as NDdiag

Getting Initial Data

Start dumps, lateral boundary condition (LBC) files and ensemble data can be obtained from the Met Office archive system (MASS). This is accessed using the MOOSE client. This covers the latest five years. Start dumps from earlier periods can be constructed as GRIB files from ECMWF data.

To get the data, create a help desk ticket providing the following information,

• dates and times required,
• project name,
• estimate of the data volume in GB,
• where in MASS the data is located if it is not one of the standard sets below.

Getting data from the Met Office

The start dumps are now stored in MASS, which can be accessed via MONSooN or JASMIN using the MOOSE interface.

Instructions for setting up external access to MASS from JASMIN are available on the ​Collaboration Twiki.

The structure of the MASS repository has changed over the years due to changes in storage formats and file naming conventions. The script get_dump​, which should be run on Monsoon, does a good job of getting a start dump. It takes a single argument which is a date:

   get_dump yyyymmddhh

The script deals with dates from the earliest time 2006/01/01 0Z and is know to work up to 2019/06/26.

To get data for 28/Sep/2011 we would type,

To find out whether the data exists,

moo ls moose:/opfc/atm/global/rerun/201109.file

Generally we prefer to get the output from the global runs - these have "qwqg" in the title; otherwise we get the global update - these have "qwqu" in the file name.

For further information on using MOOSE on MONSooN and JASMIN see: ​Getting started with MOOSE on MONSooN and JASMIN.

UKV start dumps

The UKV start dumps are in MASS with path names like,

• moose:/opfc/atm/ukv/rerun/201108.file/20110810_qwqv03.T+1

• moose:/opfc/atm/ukv/rerun/201108.file/20110810_qwqv06.T+1
• etc.

UKV forecasts and analyses

The UKV forecasts and analyses are in the MASS with path names like,

moose:/opfc/atm/ukv/prodm/YYYY.pp/prodm_op_ukv_YYYYMMDD_AA_NNN.pp for the multilevel fields and

moose:/opfc/atm/ukv/prods/YYYY.p/prods_op_ukv_YYYYMMDD_AA_NNN.pp

where

• YYYY = year e.g. 2011,
• MM = month e.g. 05,
• DD = day e.g. 21
• AA = analysis time = 03, 09, 15 or 21
• NNN = the part of the forecast - in steps of two from 000 to 036. e.g. 000, 002, 004 … 036

MOGREPS-R files

Ensemble fields are in:

moose:/opfc/atm/mogreps-g/rerun/YYYYMM.file moose:/opfc/atm/mogreps-r/rerun/YYYYMM.file

where YYYY = year e.g. 2011, MM = month e.g. 07.

At minimum, to re-run MOGREPS-R you need the analysis files in the mogreps-r path e.g. 20110722_qwqy06.T+0.18km 20110722_qwqy18.T+0.18km, and all the perturbations files e.g. 20110722_perts.qwey06.oper??.pp1 where ?? goes from 00 to 23 members. Also in the mogreps-g path, you need the boundary files e.g. 20110722_qweg00.oper??.FRAMES.EY.tar.gz.

Getting data from ECMWF

The standard data provided is from ECMWF's operational data. It is a deterministic forecast from the atmospheric model, version 1, analysis. It is not ERA. Data prior to X is in GRIB1 format, after that it is GRIB2. The GRIB start dumps are created by concatenating the following fields:

• skin temperature,
• surface pressure,
• land-sea mask,
• geo-potential,
• temperature,
• specific humidity,
• U and V wind velocities

In contrast, a UM dump contains typically a hundred fields, so the GRIB start dumps need to be reconfigured.

External Links

​NCAS Climate and High Impact Weather

​NCAS Air Quality

​Mesoscale Group, University of Reading

W. McGinty

26 June 2019