Observations for


a) Dekadal (i.e., ~10-daily) precipitation estimates for the selected region from Dec 2002 to the present.

b) Same as (a) (solid black line) with the addition of the recent short-term average precipitation for the same region (grey dotted line). The blue (red) bars are indicative of estimates that are above (below) the short-term average. Note that the short-term average precipitation data has been smoothed.

c) Same as (a) for the current calendar year (thick black line), as indicated by the axis labels. Precipitation estimates from previous years are also shown (blue-1 yr from present; magenta-2 yrs from present; grey-3 yrs from present).

d) Cumulative dekadal precipitation estimates (solid black line) and the cumulative recent short-term average precipitation (grey dotted line) for the most recent 12-month period in the selected region. The blue (red) bars are indicative of estimates that are above (below) the short-term average.

NOTE: The recent short-term average (from 2003 to the most recent complete year) of precipitation should not be interpreted as a climatological normal, which is typically based on a long-term (e.g., 30-year) time series. The length of this short-term average will increase over time as more data become available. (An additional year of data will be included in the average during January of each year.)

*The dekadal precipitation estimates have been aggregated from the daily data. Every month has three dekads, such that the first two dekads have 10 days (i.e., 1-10, 11-20), and the third is comprised of the remaining days of the month. Therefore, the length of the third dekad of each month is not consistent and varies from 8-11 days, depending on the length of the month.

Monthly Rainfall Estimates

Accumulated rainfall during the most recent month based on estimates from the Climate Prediction Center Morphing technique.

The interface allows users to analyze recent rainfall in the desert locust breeding areas via maps and location-specific time series.


Joyce, R.J., J.E. Janowiak, P. A. Arkin and P. Xie, 2004: CMORPH: A Method that Produces Global Precipitation Estimates from Passive Microwave and Infrared Data at High Spatial and Temporal Resolution. J. Hydrometeorology, 5, 487-503.

Dataset Documentation

Precipitation Estimates

Daily precipitation estimates on a 0.25 x 0.25 deg. lat/lon grid
Data Source
Climate Prediction Center Morphing Technique (CMORPH)


Access the dataset used to create this map.

How to Use the Monthly Rainfall Analysis Tool

About the Tool

This tool enables users to view maps of satellite estimates of monthly rainfall over areas within the range of the Desert Locust, from West Africa to South Asia. The tool uses Climate Prediction Center Morphing Technique (CMORPH) satellite-estimated precipitation data from January 2003 to the present. The data are updated every month. This tool enables users to:

This tool can be helpful in seeing where recent rainfall has occurred that might support the growth of green vegetation that could attract Desert Locusts.

For further information about the relationship between satellite-estimated rainfall and Desert Locust activity, or if you have questions about how to interpret the data in this tool, please contact Pietro Ceccato (pceccato@iri.columbia.edu).

How to Use this Tool

To return to the menu page, click the "Locust" link at the top left corner of the page.

Click and Drag to Zoom in to a Region on the Map:

  1. Click the left mouse button at the upper-left corner of the region to which you would like to zoom.
  2. While holding down the mouse button, drag the mouse to the lower-right corner of the region to which you would like to zoom.
  3. Release the left mouse button. The map will redraw automatically.
Zoom Out to the Full Map Extent:
  1. Move your mouse over the map until you see several icons appear above the map.
  2. Click the icon representing a magnifying glass.
  3. The map will redraw automatically.
Overlay or Remove Administrative Boundaries on the Map:
  1. Move your mouse over the map until you see several icons appear above the map.
  2. Click the "Layers" icon.
  3. Select from among the labeled check boxes that appear to select the administrative boundaries of interest.

Change the Date of the Map:

Find the the date of the estimated monthly rainfall map by moving your mouse over the map until you see several icons appear above the map. Ensure that the "Time" icon has been selected and a text box will appear above the map with the date inside.
  1. To step forward or backward by one month, click the corresponding arrow buttons to the left or right of the date text box, and the map will automatically refresh.
  2. To manually change the date of the map, type your month and year of interest into the text box. Use a format such as "Jan 2008", and press "enter".

Generate Time Series Analyses:

  1. From the "Spatially Average Over" drop-down menu select the size of a rectangular box (e.g., 27 x 27 km box) over which estimated rainfall will be averaged to produce time series.
  2. Click on a location on the map to generate time series graphs of precipitation estimates for the selected region.

Please feel free to email us with any questions or comments.


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