Percent Occurrence of Climate Conditions Suitable for Malaria Transmission

Precipitation
(P > 80mm)

Temperature
(18°C < T < 32°C)

Relative Humidity
(RH > 60%)

Seasonal Climatic Suitability for Malaria Transmission

This map shows the number of months suitable for malaria transmission, based on climatological averages. Suitability is defined as the coincidence of precipitation accumulation greater than 80 mm, average temperature between 18°C and 32°C, and relative humidity greater than 60%.

Temperature, precipitation and relative humidity are factors which drive the abundance and feeding cycle rate of Anopheles mosquitoes which transmit malaria. Temperature also drives the development rate of Plasmodium parasite within the mosquito vectors. The combined value for climate suitability is an indication of the lower limit for potential malaria transmission.

References:

Grover-Kopec, E. K., et. al. (2006). Web-based climate information resources for malaria control in Africa. Malaria Journal, 5:38.

Dataset Documentation

Temperature and precipitation climatology is compiled on a 0.5° x 0.5° lat/lon grid from University of East Anglia’s Climate Research Unit (CRU). Relative Humidity climatology is compiled on a 2.5° x 2.5° lat/lon grid from NCEP/NCAR CDAS/Reanalysis.

This map is based on a theoretical model of climate data and is not based on actual malaria data.

Precipitation Climatology

Data
Monthly precipitation over land areas on a 0.5° x 0.5° lat/lon grid
Base Period for Climatology
1951-2000
Data Source
University of East Anglia (UEA CRU TS 2.0)

Temperature Climatology

Data
Monthly temperature over land areas on a 0.5° x 0.5° lat/lon grid
Base Period for Climatology
1951-2000
Data Source
University of East Anglia (UEA CRU TS 2.0)

Relative Humidity Climatology

Data
Monthly specific humidity data (converted to rh) on a 2.5° x 2.5° lat/lon grid
Base Period for Climatology
1951-2000
Data Source
National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR CDAS/Reanalysis)

Epidemiological Mask

Mask
illustrating areas where malaria is considered to be epidemic. Areas where malaria transmission is considered absent or endemic are therefore excluded. This mask is based purely on climatic constraints to malaria transmission, and does not yet account for areas in the northern and southern margins of the continent where control has eliminated malaria risk.
Reference
WHO: Final report on the 3rd meeting of the RBM Technical Resource Network on Epidemic Prevention and Control. Geneva: World Health Organization; 2002.

Dataset

Access the dataset used to create this map.

Helpdesks

Contact help@iri.columbia.edu with any technical questions or problems with this Map Room, for example, the forecasts not displaying or updating properly.

Instructions

The default map displays the number of months suitable for malaria transmission over Africa.

The interface consists of a clickable map that allows users to generate customized analyses for a location of interest. When a desired location is clicked, four time series graphs are generated that provide analyses of how often suitability has occurred in the historical record (1951-2000).

The "Map Shows" drop down menu allows users to isolate a single climatic variable and show the percent occurrence of malaria suitability based on that variable.

The interface consists of a clickable map that allows users to generate customized time series graphs. When a desired location is clicked, the most recent 12 month LST time series will be generated.