Read this first: Using future climate projection data
- These datasets are long term climate projection based on simulation process; they are NOT long term forecast. They are scenarios that show plausible future change in climate characteristics under different changes in atmospheric greenhouse gases, especially CO2.
Available datasets are as follows:
• ECHAM4 GCM – A2 and B2 emission scenarios.
• ECHAM5 GCM – A1B emission scenario.
• Ensemble A1B emission scenarios that represent wet scenario, dry scenario, high temperature change scenario and low temperature change scenario.
- Even though, data is available is daily format, however, use of data from these datasets should be under context of climate, which take into consideration pattern of weather over long period of time, e.g. decade or longer such as 30-year period. User may need to conduct pre-analysis to prepare data into proper use, e.g. average temperature or annual rainfall or seasonal rainfall over the decade, wettest year or driest year of the decade for extreme case assessment, change in return period of extreme weather, rainfall intensity, duration of warm/cool period over the year, etc. Data of specific year may not be used explicitly because it is not real calendar year, but it only represents weather condition roughly around that period of time in the decade.
- These datasets are result of simulation process and may not be equally accurate throughout the domain. Data in the coastal area seems to be less accurate than the in-land area. User will need to compare simulated data with observe data and work out the proper way to adjust model bias, however, comparison should base on climate characteristics e.g. average rainfall over the decade, total rainfall of the wettest/driest year of the decade, etc. User may have to come up with creative way for alternate choice in making use of simulated data, e.g. use of relative change over 2 periods of time and apply it to the baseline observed data to come up with a scenario for climate change risk/impact assessment, etc.
- Data is available in grid size of approximately 20x20 km, the reference lat. / lon. is the center of the grid. Even though, these datasets had been verified to certain extent, but there may still be some noises or error in some grids, such as unusual amount of rainfall in a single day in certain grids. Therefore, users will have to check the data prior to their use and adjustment on simulated data may be required. It is suggested that use of data from pinpointed grid, or single grid should be avoided, use of average value from multiple grids is recommended for study or assessment of small area.
- The datasets consist of these climate variables:
• Maximum temperature - Tmax (°C)
• Minimum temperature – Tmin (°C)
• Precipitation (mm)
• Wind speed (m/s)
• Wind direction (degree from north)
• Solar Radiation (W/m2)
Please note that data is available in daily format, however, some models may only have 360 days for a year and some models are true calendar year.
- In order to avoid large data size in the distribution process, the system will limit each data extraction to 10 years per variable and distribution format is 1 file per 1 variable and 1 year.