In most of Eritrea, the majority of rainfall occurs during July to August. In the eastern portion of the country, where a steep escarpment degrades towards the Red Sea, rainfall is considerably lower, and peaks from October to January. Both ground station measures and satellite-derived estimates of rainfall are potential proxies for use by malaria control staff.

In this exercise, we investigate the relationship between malaria and different sources of environmental information such as rainfall derived from satellite and vegetation status. We will use:

1. Rainfall Estimates derived from the CMAP products available in the IRI Data Library
   The rainfall estimates are available at 2.5 deg spatial resolution for the period 1979 to 2010.
   References: Xie, P. and P. A. Arkin, 1996: and Xie, P. and P. A. Arkin, 1997

2. Rainfall Estimates derived from the TRMM products available in the IRI Data Library
   The rainfall estimates are available at 0.25 deg spatial resolution for the period 1 Jan 1998 to 30 Jun 2011.
   References: Huffman et al. 2007
   

3. Vegetation index Normalized Difference Vegetation Index (NDVI) version g available in the IRI Data Library
   The NDVI version g data are available at 8km spatial resolution for the period 1981 to 2006.
   References: Pinzon et al., 2005; Tucker et al., 2005
   

4. Additional climatic and environmental variables can be used for this exercise. We encourage the student to investigate the relationship between malaria incidence and other climatic/environmental factors by searching other potential factors available in the data library. [Hint: investigate the relationship between malaria incidence and sea surface temperature, El Niño, land and air temperature.] For more information on how to access the data, see screencast entitled “An Introduction to the IRI Data Library” available in the Fire module .