The latest version of the system incorporates an expanded set of variables and indices, available for the historic, near real-time and short-term forecast periods, and new fuctionality to more easily view warning information based on high and low values of the variables and indices. A new dedicated 'warnings' tab shows specific warnings for the next 10 days of the short-term forecast. The seasonal forecasts of precipitation are also updated to provide a wide range of probabilistic forecast information such as the probability of seasonal precipitation below the median or lower tercile, or the probability of severe or extreme drought and pluvial conditions. A user-guide will be added soon.
The Madagascar Flood and Drought Monitor is an operational system for early warning of flood and drought conditions across the country. It has been developed by Princeton Climate Institute (PCI) in collaboration with University of Southampton and Princeton University, with funding support from UNESCO Intergovernmental Hydrology Programme (IHP) and US Army Corps of Engineers. The system is based on a set of ground, satellite and modeled datasets, which are combined to provide a consistent picture of hydrological conditions close to real-time, as well as forecasts out to 7-days for floods and out to 6 months for drought.
The system is operational and is updated every day, about 1-2 days behind real-time. It runs a hydrological model over the domain at 5km resolution that is forced by a hybrid reanalysis-satellite dataset of precipitation, temperature and other meteorological variables. The model runoff is routed through a vector river model to produce estimates of streamflow at 1000’s of river reaches across the domain. The model outputs are used to calculate drought indices, which are also updated every day. Once a month an ensemble of seasonal forecasts is made of precipitation and temperature, which are used to drive the hydrological model out to 6 months into the future. Currently the system uses the ECMWF climate forecast system to produce the precipitation and temperature forecasts, which is one of the best performing models for the region, and has 51 ensemble members. The precipitation and temperature data are downscaled to 5km resolution and bias-corrected to remove any biases from the climate forecast model. The hydrological model outputs are used to calculate forecasts of drought indices and other statistics such as probability of drought. The forecast ensemble is represented by the mean and some other statistics of its distribution such as the 5th and 95th percentile.
The main tab of the MDG-FDM provides visualization and access to the data of the monitor. The top bar shows the name of the system and a menu with a series of tabs. The tabs provide access to the different parts of the MDG-FDM. This includes tabs for current conditions, short-term forecasts, seasonal forecasts, help, etc.
Current Conditions – This tab shows a summary of current conditions and the latest forecast.
Current Warnings – This tab shows a summary of current warnings for the next 9 days of the forecast.
District Summary - This analysis tab shows detailed information on current and short-term (10-day) forecast conditions, with a focus on hydrological variables at district scale, and streamflow at a series of points of interest.
Seasonal Forecasts - This analysis tab shows more detailed information on seasonal (6-month) forecast conditions for the country and districts, with a focus on precipitation (hydrological forecast variables and indices are in development).
About/help – this provides background information about the MDG-FDM, as well as help information on the system and its various functions.
The following varibales and indices are included in the system: