About

The Cambodia Climate Change Toolbox is an open-source information portal that provides projections and data for climate parameters in Cambodia at the country, provincial, district, and local levels. The toolbox has been developed to support the decision-making process of the Government of Cambodia.

The toolbox is built on R Shiny to allow for easy customization and updating. The four main toolbox components, which can be selected on the navigation bar at the top of the page, are:

1. Interactive map: the interactive map is the primary component of the tool, allowing users to query climate data in a variety of ways including by province, point location, or area location. Users can define the climate condition they are interested in by selecting the desired climate scenarios, climate parameter, and season. The interactive map also provides information on projected extreme weather events.

2. Country climate profile: a dual-map view showing projected precipitation and maximum temperature for the 2050s for the country. This component also includes a table providing current and projected changes in temperature and rainfall that can be sorted by province. Users can select the climate condition (based on GCM) and season.

3. Province climate profile: a map showing projected precipitation and maximum temperature in 2050s for the selected province. This component also includes a table providing projected changes in temperature and rainfall that can be sorted by district. Users can select the climate condition (based on GCM) and season.

4. About: reference information on the data sources used and relevant terminology necessary to understand and use the toolbox.

The Manual of Cabodia Climate Toolbox (English language) can be founded here.

Data

The toolbox has incorporated two souces of data: MRC CCAI and NASA NEX-GDDP:

MRC CCAI: Mekong River Commission - Climate Change and Adaptation Initiative is a collaborative effort among MRC Member Countries – Cambodia, Lao PDR, Thailand and Viet Nam, to demonstrate and share adaptation strategies. One of major outputs of the program is the high resolution climate change data set for Lower Mekong Basin using SimCLIM system.

MRC conducted an analysis and selected three GCMs to predict distinct future trends (MRC CCAI 2015b: Defining basin-wide climate change scenarios for the Lower Mekong Basin (LMB). Climate Change and Adaptation Initiative, Mekong River Commission, Lao PDR):

  • GISS-E2-R-CC: drier condition,
  • IPSL-CM5A-MR: wetter wet season and drier dry season.,
  • GFDL-CM3: wetter condition.
  • It is important to note that the IPSL-CM5A-MR model predicts less extreme changes in each season than the GFDL-CM3 and GISS-E2-R-CC models do. These three GCMs were chosen from a shortlist of 15 by the MRC to represent the ‘lower’ bound of projected future impacts (drier condition), ‘medium’ scenario (wetter wet season and drier dry season) and ‘upper’ bound (wetter condition).

    NASA NEX-GDDP: The NASA Earth Exchange Global Daily Downscaled Projections (NEX-GDDP) dataset is comprised of downscaled climate scenarios for the globe that are derived from the General Circulation Model (GCM) runs conducted under the Coupled Model Intercomparison Project Phase 5 (CMIP5). These runs were conducted across two of the four greenhouse gas emissions scenarios known as Representative Concentration Pathways (RCPs) for the periods from 1950 through 2100 with a spatial resolution of 0.25 degrees (~25 km x 25 km).

    There are some limitations with the SimCLIM system data available from the MRC. The MRC SimCLIM data is only available as monthly averages over ten year periods. This temporal resolution does not allow for the assessment or projection of extreme events that occur over periods of days to weeks. The NASA NEX-GDDP, which is a daily global data set downscaled using the Bias Corrected – Spatial Derivation (BCSD) method, was included to overcome this limitation and incorporate extreme events. The GFDL-CM3 has been used to analyze precipitation extreme events and the IPSL-CM5A-MR has been used to analyze temperature extreme events.

    Acknowledgements

    The development of this toolbox was made possible through the support of the Mekong River Commission (MRC) and the Cambodia National Mekong Committee (CNMC), with technical support from the International Centre for Environmental Management (ICEM). The climate change and meteorological data used in the toolbox would not be available without the support of both agencies, and their collaboration together and with ICEM.
    The MRC downscaled the three models used in the toolbox using SimCLIM and tailored the results to each Lower Mekong Basin country. This high resolution data was then distributed to researcher institutes in this region, including the CNMC. The CNMC then graciously provided ICEM and MOE permission to access, analyze, and present this data.