Southeast Asian Climate Assesment

 
 

SA-OBS gridded dataset

 

This is the download page for the daily gridded observational dataset for precipitation and temperature Southeast Asia called SA-OBS. Bookmark this page for future direct access!

Actual version and update policy
SA-OBS datafiles
Access to smaller chunks
Access to underlying station data
Citation and acknowledgement
Guidance for users
Terms of use

 

Actual version and update policy

 

SACA&D staff will maintain and update the SA-OBS gridded dataset.

 
 

Version

Release date

Period covered

Modification

2.0

September 2018

1981-01-01 - 2017-12-31

Updates are included for Singapore, Indonesia, Australia and GHCN-D. The station database has been cleaned from duplicate series.

1.0

April 2017

1981-01-01 - 2014-12-31

First release of a new dataset.

 

SA-OBS datafiles

 

The datafiles contain gridded data for 4 elements (daily mean temperature TG , daily minimum temperature TN , daily maximum temperature TX and daily precipitation sum RR ). They cover the area: 20S-25N x 80E-180E. The data files are in compressed NetCDF format and range in size from 24 Mb - 175 Mb. There are 2 different grid resolutions. Data is made available on a 0.1 and 0.25 degree regular lat-lon grid for version 3.0e. Besides 'best estimate' values, separate files are provided containing daily standard errors and elevation. The Global 30 Arc-Second Elevation Data Set ( GTOPO30 ), a global raster Digital Elevation Model (DEM) with a horizontal grid spacing of 30 arc seconds (approximately 1 kilometer) developed by USGS is used for the elevation file.

 

Version 2.0

Best estimate

Daily standard error

Elevation

0.25 deg. regular grid

TG TN TX RR

TG TN TX RR

all elements

0.50 deg. regular grid

TG TN TX RR

TG TN TX RR

all elements

Version 1.0

Best estimate

Daily standard error

Elevation

0.25 deg. regular grid

TG TN TX RR

TG TN TX RR

all elements

0.50 deg. regular grid

TG TN TX RR

TG TN TX RR

all elements

 

Access to underlying station data

 

A list of station series used for the actual version of SA-OBS is provided for TG , TN , TX and RR . Part of these series are freely available from the daily data webpage. For the remaining series we do not (yet) have the release permission from the data owners.

 

Citation and acknowledgement

 

Whenever you publish research or applications based on these gridded data products, you should include the following acknowledgement and citations.

SA-OBS temperature and precipitation:
"We acknowledge the SA-OBS dataset and the data providers in the SACA&D project (https://sacad.database.bmkg.go.id)"
"Else J.M. van den Besselaar, Gerard van der Schrier, Richard C. Cornes, Aris Suwondo, Iqbal and Albert M.G. Klein Tank. 2017: SA-OBS: a daily gridded surface temperature and precipitation dataset for Southeast Asia. Journal of Climate, doi:10.1175/JCLI-D-16-0575.1 "

 

Guidance for users

 

Gridded datasets derived through interpolation of station data have a number of potential inaccuracies and errors. These errors can be introduced either by the propagation of errors in the station data or by limitations in the ability of the interpolation method to estimate grid values from the underlying station network. An important finding is that, in areas where relatively few stations have been used for the interpolation, both precipitation and temperature are over-smoothed. This leads to reduced interpolated values relative to the "true" area-averages, in particular for extremes.

 

Terms of use

 

The SACA&D data policy applies. These observational data are strictly for use in non-commercial research and non-commercial education projects only. Scientific results based on these data must be submitted for publication in the open literature without any delay linked to commercial objectives. If you are unsure about the terms "commercial", "research", and "education", please contact the SACA&D staff at aris.suwondo@bmkg.go.id for clarification.