Introduction to CMADS

The China Meteorological Assimilation Datasets for the SWAT model (CMADS) incorporates technologies of the China Land Data Assimilation System. It was constructed using multiple technologies and scientific methods, including loop nesting of data, projection of resampling models, and bilinear interpolation. The CMADS series of datasets can be used to drive various hydrological models, such as SWAT, the Variable Infiltration Capacity (VIC) model, and the Storm Water Management model (SWMM). It also allows users to conveniently extract a wide range of meteorological elements for detailed climatic analyses. Data sources for the CMADS series include nearly 40,000 regional automatic stations under China’s 2,421 national automatic and business assessment centres(Meng et al.,2017). This ensures that the CMADS datasets have wide applicability within the country, and that data accuracy was vastly improved.

   The CMADS series of datasets has undergone finishing and correction to match the specific format of input and driving data of SWAT models. This reduces the volume of complex work that model builders have to deal with. An index table of the various elements encompassing all of East Asia was also established for SWAT models. This allows the models to utilize the datasets directly, thus eliminating the need for any format conversion or calculations using weather generators. Consequently, significant improvements to the modelling speed and output accuracy of SWAT models were achieved.

   Most of the source data in the CMADS datasets are derived from CLDAS in China and other reanalysis data in the world. The integration of air temperature, air pressure, humidity, and wind velocity data was mainly achieved through the LAPS/STMAS system. Precipitation data were stitched using CMORPH’s global precipitation products and the National Meteorological Information Center’s data of China (which is based on CMORPH’s integrated precipitation products). The latter contains daily precipitation records observed at 2,400 national meteorological stations and the CMORPH satellite’s inversion precipitation products.The inversion algorithm for incoming solar radiation at the ground surface makes use of the discrete longitudinal method by Stamnes et al(1988)to calculate radiation transmission (Shi et al., 2011). The resolutions for CMADS V1.0, V1.1, V1.2, and V1.3 were 1/3°, 1/4°, 1/8°, and 1/16°, respectively (Meng et al.,2016).

   The China Meteorological Assimilation Datasets for the SWAT model (CMADS) was completed over the 9 year period of 2008.01.01 through 2016.12.31 and has been used in many watersheds in China(Meng et al.,2017b). The current CMADS will be extended as real time product in the future.


1.Meng, X.; Wang, H.; Cai, S.; Zhang, X.; Leng, G.; Lei, X.; Shi, C.; Liu, S.; Shang, Y. The China Meteorological Assimilation Driving Datasets for the SWAT Model (CMADS) Application in China: A Case Study in Heihe River Basin. Preprints 2016, 2016120091 (doi: 10.20944/preprints201612.0091.v2)

2.Meng, X.Y.,Dan, L.Y. & Liu, Z.-H. Energy balance-based SWAT model to simulate the mountain snowmelt and runoff – taking the application in Juntanghu watershed (China) as an example. J. Mt. Sci. 12(2), 368-381 (2015).

3.Meng, X. Y., Wang, H., Liu, Z. H., Shi, C. X. & Liu S. Y. Simulation and verification ofland surface soil temperatures in the Xinjiang region by the CLM3.5 model forced by CLDAS. Acta Ecol. Sin. 37(3), 979-995 (2017a).

4.Meng,X.Y.,Wang,H.,Lei,X.H.,Cai,S.Y.,Wu,H.J.Hydrological Modeling in the Manas River Basin Using Soil and Water Assessment Tool Driven by CMADS. Tehnicki Vjesnik -Technical Gazette,24,(2),525-534.DOI: 10.17559/TV-20170108133334(2017b)

5.Stamnes, K., Tsay, S.C., Wiscombe, W. & Jayaweera, K. Numerically stable algorithm for discrete-ordinate method radiative transfer in multiple scattering and emitting layered media. Appl. Opt. 27(12), 2502-2509 (1988). doi: 10.1364/AO.27.002502.

6.Shi, C. X., Xie, Z. H., Qian, H., Liang, M. L. & Yang, X. C. China land soil moisture EnKF data assimilation based on satellite remote sensing data. Sci. China Earth Sci. 54(9),1430-1440 (2011).

7.Wang, Y.J. & Meng, X.Y. Snowmelt runoff analysis under generated climate change scenarios for the Juntanghu River basin in Xinjiang, China. Tecnología y Ciencias del Agua, 7(4), 41-54 (2016).


Download CMADS data

This website allows you to download CMADS data in SWAT file format for a given location and time period. In CMADS V1.0 (at a spatial resolution of 1/3°), East Asia was spatially divided into 195 × 300 grid points containing 58,500 stations. Despite being at the same spatial resolution as CMADS V1.0, CMADS V1.1 contains more data, with 260 × 400 grid points containing 104,000 stations. For both versions, the stations’ daily data include average solar radiation, average temperature, average pressure, maximum and minimum temperature, specific humidity, cumulative precipitation, and average wind velocity.

   Please do not hesitate to mail us ( or if you need our assistance when you have problems using CMADS data.

Download CMADS V1.0


Total data: 33600MB

Occupied space: 35200MB

Time: From year 2008 to year 2016

Time resolution: Daily

Geographical scope description: East Asia

Longitude: 60°E

The most east longitude: 160°E

North latitude: 65°N

Most southern latitude: 0°N

Number of stations: 58500 stations

Spatial resolution: 1/3 * 1/3 * grid points

Downlad CMADS V1.0 (English)

Downlad CMADS V1.0 (Chinese)

Download CMADS V1.1


Total data: 50000MB

Occupied space: 50000MB

Time: From year 2008 to year 2014

Time resolution: Daily

Geographical scope description: East Asia

Longitude: 60°E

The most east longitude: 160°E

North latitude: 65°N

Most southern latitude: 0°N

Number of stations: 104,000 stations

Spatial resolution: 1/4 * 1/4 * grid points

Download CMADS V1.1 (English)

Download CMADS V1.1 (Chinese)


1. Download CMADS.7z and Find out the CMADSV1.0station.zi...


China MeteorologicalAssimilation Driving Datasets for the...