POAMA-2 Hindcasts and Forecasts on OPeNDAP Server

Introduction

POAMA-2 hindcast and realtime data are now available on an OPeNDAP server.

Conditions of Use

The data is made available for research collaboration only. Full conditions of use.

The Model Configuration

POAMA-2 consists of both a seasonal and a monthly forecast system using version 2.4 of the model. POAMA-2 is also a multi-model ensemble consisting of three different model configurations. For the seasonal forecasts these configurations are called p24a, p24b and p24c and for the multi-week forecasts they are called m24a, m24b, m24c

Model setsm24a, m24b, m24c
Ensembles11 Members and 1 Ensemble Mean. (e00 -> e10 & emn)
Forecast Availability9 month lead times are available from 3rd of May, 2012
Forecast FrequencyForecasts are available on a weekly basis.
Forecast Lead TimeLead time to 270 days.
Hindcast Availability1980-2011
Hindcast Frequency Hindcasts start on the 1st, 11th and 21st of the month.
Hindcast Lead TimeLead time to 270 days for years 1981-2011.

Data available - Structure

A detailed description of the POAMA files is provided on a separate page.

Data available - Structure on the OPeNDAP Server

The data that is available on the OPeNDAP Server is catalogued under the following folder/directory structure.

Higher Level Directories

These are the directories that are available on the OPeNDAP server. These will be changed shortly to reflect better navigation.

  1. POAMA 1.5 Data Catalog
    1. POAMA 1.5 Real Time Forecasts
    2. POAMA 1.5 Monthly Hindcasts (from 1980)
    3. POAMA 1.5 Model Climatologies
  2. POAMA 2.4 Control Runs
    1. POAMA 2.4A Control Runs
    2. POAMA 2.4B Control Runs
    3. POAMA 2.4C Control Runs
  3. POAMA 2.4 Multiweek Hindcasts from 1980
    1. POAMA 2.4A Multiweek Hindcasts (from 1980)
    2. POAMA 2.4B Multiweek Hindcasts (from 1980)
    3. POAMA 2.4C Multiweek Hindcasts (from 1980)
  4. POAMA 2.4 Multiweek Real Time Forecasts
    1. POAMA 2.4A Multiweek Real Time Forecasts
    2. POAMA 2.4B Multiweek Real Time Forecasts
    3. POAMA 2.4C Multiweek Real Time Forecasts
  5. PEODAS Re-Analysis
  6. PEODAS Real Time
    1. main
    2. multi_week_catchup
    3. seasonal_catchup

Lower Level Directories

In the POAMA Hindcast and Forecast folders, there are a number of ensemble folders and climatology folders:

Multi Model Configurations and Multi Model Anomanlies

Three different model configurations are used (p24a, p24b, p24c) for the seasonal and (m24a, m24b, m24c) for the monthly/multi-week configurations. These should be used together to form a multi-model ensemble. Ensure that you use the Model's Climatology with the Model's Ensemble or Ensemble Mean when determining Multi Model Anomalies.

Note about Model Climatology

Model climatology is calculated by averaging all ensemble members, for a given start date in the year, over all the years specified in the climatology. The climatologies are lead-time dependent.

The model climatology files will have the same format as the individual forecasts, one can then calculate anomalies by subtracting the climatology from the forecast file. Be aware that the climatology file may be shorter that the individual ensemble file.

NetCDF data files available

The following table is a list of the main file types that are available on the OPeNDAP Server.

FileSizeDescriptionModel File
dag_YYYYMMDD.nc~300 MBDaily Atmosphere file - 270 daysNo
ma_YYYYMMDD.nc ~18 MB Monthly Atmosphere fileYes
oa_YYYYMMDD.nc~96 MBMonthly Ocean fileYes

A detailed description of the POAMA files is provided on a separate page.

Known Issues

IssueFiles affectedDetails
Surface wetness units All atmospheric files: ma, sa, dag, dar sfc_wet units are incorrectly reported as "m" (metres), not "mm" (millimetres).

OPeNDAP server

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