GRENE-ei CAAM 0.05°×0.05°
Grid Daily Precipitationin Thailand (prototype)
1. IDENTIFICATION INFORMATIONName

GRENE-ei CAAM 0.05°×0.05° Grid Daily Precipitation in Thailand (prototype)

Edition

1.0DOI

doi:10.20783/DIAS.233 [https://doi.org/10.20783/DIAS.233]

Metadata
Identifier

GRENE_ei_CAAM_Thai_Grid_DailyRain_prototype20230727071653DIAS20221121113753-en

2. CONTACT
2.1 CONTACT on DATASET
Name

Tomoshige Inoue

Organization

University of Tsukuba

AddressJapan

E-mailinoue.tomoshige.ke@u.tsukuba.ac.jp

2.2 CONTACT on PROJECT2.2.1 Data Integration and Analysis System
Name

DIAS Office

Organization

Japan Agency for Marine-Earth Science and Technology

Address

3173-25, Showa-Cho, Kanazawa-ku, Yokohama-shi, Kanagawa, 236-0001, Japan

E-maildias-office@diasjp.net

3. DOCUMENT AUTHOR
Name

Tomoshige Inoue

Organization

Japan Agency for Marine-Earth Science and Technology

4. DATASET CREATOR
Name

Kooiti Masuda

Organization

Japan Agency for Marine-Earth Science and Technology1

5. DATE OF THIS DOCUMENT
2023-07-27

6. DATE OF DATASET
�creation : 2015-03-20
�revision : 2015-11-30

7. DATASET OVERVIEW
7.1 Abstract
This is a prototype of 0.05°(lat) x 0.05°(lon) gridded data set of spatially-interpolated daily
precipitation made from station precipitation in Thailand. Most of the data are obtained from theThai Meteorological Department (TMD) by Prof. Jun Matsumoto (Tokyo Metropolitan University/JAMSTEC).
We have not taken account of topographical effects, nor systematic errors of raingauges. In ourproduct, data are given on grid boxes over land whose altitude is below 500 m only. Furthermore,those grid boxes which are far from any observing stations to be void of data. The threshold distanceis predetermined by subjective decision of the analyst. The production of this data set is also apart of GRENE-ei (Green Network of Excellence, environmental information) CAAM (Climatic Changesand Evaluation of Their Effects on Agriculture in Asian Monsoon Region) of MEXT (the Ministry ofEducation, Culture, Sports, Science and Technology in Japan).

7.2 Topic Category(ISO19139)
�climatologyMeteorologyAtmosphere

7.3 Temporal Extent
Begin Date

1979-01-01

End Date

2011-12-31

Temporal
Characteristics

Daily

7.4 Geographic Bounding Box
Northlatitude

bound 20.5

Westlongitude

bound 97Eastboundlongitude

106

South
latitudebound 5.5

7.5 GridDimension NameDimension
Size Resolution Unit
(slice number ofthe dimension)2column

180

3 (minute)row3003 (minute)

7.6 Geographic Description
Asia

7.7 Keywords
7.7.1 Keywords on Dataset
Keyword TypeKeyword

Keyword
Name

theme

Atmosphere > Precipitation > Precipitation Amount

GCMD_science

theme

HYDROLOGY > Precipitation,
Precipitation

theme

Water, Climate

GEOSS

place

Asia > South Eastern Asia > Thailand

Country

ATMOSPHERICPROCESSES

thesaurus> AGU

7.7.2 Keywords on Project
7.7.2.1 Data Integration and Analysis SystemKeyword Type

Keyword

KeywordNamethesaurus

theme

DIAS &amp;gt; Data Integration and Analysis System

No_Dictionary

7.8 Online Resource
�GRENE-ei CAAM webpage : https://grene.agrid.org/
�file download : https://data.diasjp.net/dl/storages/filelist/dataset:233
�Maps of daily precipitation plots at stations and the gridded data (this product) : http://macroscope.world.coocan.jp/en/browse/grene/

7.9 Data Environmental Information[Processing environment]: programs written by the data set creator in Fortran 77 and Awk, Fortran77 program "Spheremap" version 99.8a from the University of Delaware, and Generic Mapping Tools(GMT) version 4.3.1 (Wessel and Smith), on Intel PC running Linux OS. [Data format]: The data are
stored in a format of ".grd" files in each day. They are made by "xyz2grd" command of GMT.

7.10 Distribution Information
nameversionspecification

NetCDFversion 3.6

Produced by program "xyz2grd" of GMT 4.3.1.

8. DATA PROCESSING3

8.1 Data Processing (1)8.1.1 General Explanation of the data producer's knowledge about thelineage of a dataset
This is a prototype of gridded data set of spatially-interpolated daily precipitation made fromstation precipitation in Thailand.
As the algorithm for interpolation, “Spheremap”of Willmott et al. (1985) is used. This isoriginally the two-dimensional spatial interpolation algorithm by Shepard (1968) which is a kindof weighted average method, but modified to work with the spherical coordinates. The algorithm
is also used by Global
Precipitation Climatology Centre (GPCC, located in the German Weather Bureau) in production of
their gridded data set of precipitation.
We have not taken account of topographical effects, nor systematic errors of raingauges.
In our product, data are given on grid boxes over land whose altitude is below 500 m only.
Furthermore, those grid boxes which are far from any observing stations to be void of data. The
threshold distance is predetermined by subjective decision of the analyst.

8.1.2 Data Source
Data Source Citation Name

Description of derived parameters and processing
techniques used

9. DATA REMARKS
Note: This dataset is a "prototype" one, and it is possible to modify the data in a final versionof dataset.
* We checked the source data and partially modified before entering them to the production.
* The following convention is assumed when monthly precipitation is calculated.
� Trace precipitation is assumed to be the same as zero.
* The selection of stations which are used for interpolation into the grid is as follows:� Such stations that are off the region of the grid to be produced by more than 2 degrees oflatitude or longitude are excluded.
* The following masking is done after spatial interpolation to the grid.
� Only those grid boxes which correspond to land whose altitude is below 500 m are consideredvalid, in order to escape an effect of mountains on precipitation. The distinction between landand sea follows that of the GPCC (Global Precipitation Climatology Centre) data set ("MonitoringProduct" as of 2004). That is, we put the missing-value flag to grid boxes which are consideredas oceanic boxes by GPCC.

4� The value in such grid boxes that are more than a certain distance farther from any stations
with valid values are considered as missing. The threshold distance is defined to be equal to thedifference of 1.6 degrees latitude along a meridian.

10. DATA POLICY
10.1 Data Policy by the Data Provider
This data set requires permission by the data provider (contact person) before you can download.
The content of this dataset should not be used for commercial purposes. The source should beproperly acknowledged in any work obtained with this dataset. The creators of this dataset are notresponsible for any loss or damage caused by using this dataset.

10.2 Data Policy by the Project
10.2.1 Data Integration and Analysis SystemIf data provider does not have data policy, DIAS Terms of Service (https://diasjp.net/en/terms/)
and DIAS Privacy Policy (https://diasjp.net/en/privacy/) apply.
If there is a conflict between DIAS Terms of Service and data provider's policy, the data provider'spolicy shall prevail.

11. LICENSE
12. DATA SOURCE ACKNOWLEDGEMENT
12.1 Acknowledge the Data Provider
12.2 Acknowledge the Project
12.2.1 Data Integration and Analysis System
If you plan to use this dataset for a conference presentation, paper, journal article, or reportetc., please include acknowledgments referred to following examples. If the data provider describes
examples of acknowledgments, include them as well.
" In this study, [Name of Dataset] provided by [Name of Data Provider] was utilized. This dataset
was also collected and provided under the Data Integration and Analysis System (DIAS), which wasdeveloped and operated by a project supported by the Ministry of Education, Culture, Sports, Scienceand Technology. "13. REFERENCES
Shepard, D., 1968. A two-dimensional interpolation function for irregularly-spaced data.
Proceedings, 1968 ACM National Conference, 517 � 524. (Reference of spatial interpolation algorithm)

5

Willmott, C.J., Rowe, C.M. and Philpot, W.D. 1985. Small-scale climate maps: a sensitivity analysis
of some common assumptions associated with grid-point interpolation and contouring. The American
Cartographer, 12, 5 � 16. (Reference of spatial interpolation algorithm)

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