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The GEOGLAM Crop Monitor for Early Warning: Strengthening Agricultural Decision Making in Countries at Risk of Food Insecurity

Crop Condition plots shown on

During the current 2018-2019 maize growing season now under harvest, southern Africa experienced some of the driest conditions in the monitoring record, dating back to 1984.  The result of these drought conditions has been crop failure across the worst-affected areas, with increasing concern for food security in the region. Early warning of these types of impending shortfalls in crop production can better inform government and humanitarian responses to disaster. To address this critical need for enhanced early warning of crop production shortfalls, the Group on Earth Observations Global Agriculture Monitoring Initiative (GEOGLAM) Crop Monitor for Early Warning (CM4EW) was developed by the GEOGLAM community with international support from the United States Agency for International Development (USAID), NASA Harvest, and a range of international partners. 

In many food-insecure countries, access to frequent and updated information on crop development and condition is scarce due to the high cost and capacity that is needed to conduct field assessments; detailed crop and food security field assessments are typically undertaken only once or twice per season. In these areas where information is scarce and uncertainty is high, consensus-driven, timely and reliable information on crop conditions and early warning of impending shortfalls of crop production are critical to achieving food security and ensuring sufficient, reliable food availability and access. Satellite-based Earth observations (EO) significantly contribute towards providing such crucial crop information, allowing decision-makers to track crop development and general crop condition throughout the growing season, and ultimately feeding into decision-making processes related to early disaster response and mitigation measures that reduce food insecurity. 

The GEOGLAM CM4EW is an international initiative that provides monthly transparent and multisource consensus assessments of crop-growing and agroclimatic conditions that are likely to impact production over at-risk countries. The main objective of the GEOGLAM CM4EW initiative is to exchange information, build consensus, and reduce uncertainty surrounding crop condition assessments in support of agricultural and humanitarian decision making. This initiative was started in 2016, building on initial work between GEOGLAM and USAID FEWS NET.

This initiative brings together the main international food security monitoring agencies and organizations that are already monitoring food security and crop conditions as part of their early warning activities, including USAID FEWS NET, WFP, UN FAO Global Information and Early Warning System (GIEWS), EC Joint Research Center (JRC), Asia RiCE, and the Intergovernmental Authority of Drought and Development Climate Prediction and Applications Centre (IGAD ICPAC), and national institutions such as the South African Agriculture Research Council (ARC), among others, to come together to develop monthly crop assessments based on satellite observations, meteorological information, field observations and ground reports, which reflect an international consensus.

The GEOGLAM CM4EW relies heavily on satellite-derived vegetation indices and agroclimatic indicators. These, along with cropland masks and crop calendars, are compiled into an online interface for use by its partners. In addition to the information provided, partners use the interface to submit monthly crop condition assessments from their own organizations’ satellite data and ground reports to build consensus crop conditions based on the best available information. This information is summarized in a monthly bulletin on crop conditions over Early Warning countries (countries at risk of food insecurity). Given the importance of forecasts in predicting crop outcomes, the GEOGLAM CM4EW has recently started to integrate regional short term and seasonal forecasts into the monthly bulletins in partnership with the USAID-funded Climate Hazards Center (CHC) at University of California Santa Barbara.  These forecasts provide insight and early warning of climate events that may impact crop production such as precipitation and temperature anomalies as well as the El Niño Southern Oscillation (ENSO). Archives of this month’s current bulletin and previous publications by the GEOGLAM CM4EW can be found at

The current 2018-19 cropping season in southern Africa, now under final harvest, marks a severe case of concern for food security in the region and where early warning of impending impacts on production is crucial.  Starting in November, the 2018 rains across many parts of Southern Africa were delayed by a month. The GEOGLAM CM4EW December 2018 assessment reported initial concern across the Southern Africa region (Figure 1), with note to the expectation for worsening conditions due to 2018-2019 precipitation forecasts. Precipitation forecasts for early 2019 provided by the USAID-supported CHC showed high probability for reduced precipitation amounts and potential for El Niño development, which could lead to further rainfall reductions across the region.

Figure 1. Southern Africa maize crop condition map from the GEOGLAM CM4EW December 2018 Bulletin.
Figure 1. Southern Africa maize crop condition map from the GEOGLAM CM4EW December 2018 Bulletin.

Following this month-delayed start of the rains that resulted in reduced planted area across some of the key maize growing areas of South Africa and Zambia, some rainfall came in early January, reducing rainfall deficits in the east. However, this was followed by a number of long dry spells, the most significant of which lasted for 4-6 weeks from mid-February to late March across the central and central west parts of the region, resulting in widespread crop wilting across the worst-affected areas of Angola, Namibia, Botswana, Zimbabwe and southern parts of Zambia and Mozambique. The high-producing region of southern Zambia was at the epicenter of this 6-week dry spell. Analysis of the Climate Hazards Center CHIRPS rainfall dataset indicates that a number of districts in southern Zambia in addition to parts of Namibia, Botswana, and southern Angola are currently experiencing their driest season since at least 1981, with implications not just for crops but also for livestock and water security. This has resulted in poor conditions across much of the region and failure across the worst-affected areas of southern Zambia shown in the most recent CM4EW April 2019 Bulletin (Figure 2).

Figure 2. Southern Africa maize crop condition map and associated pie chart showing the percent of regional production per country and associated crop condition and drivers from the GEOGLAM CM4EW April 2019 Bulletin.
Figure 2. Southern Africa maize crop condition map and associated pie chart showing the percent of regional production per country and associated crop condition and drivers from the GEOGLAM CM4EW April 2019 Bulletin.

The 2018-2019 maize harvest will complete in May, and with widespread drought conditions and below-average production across the region in addition to below-average production prospects across key producing areas, regional maize supply is of increasing concern. The CM4EW reporting has tracked this development throughout the season and aimed to give the most updated analysis to current conditions. Final post-harvest conditions for southern Africa summer crops will be reported in the CM4EW June bulletin, to be published Thursday June 6th. 

In the short time since its commencement in 2016, the GEOGLAM CM4EW has been recognized as a reliable source of vetted information on current crop conditions through its use by humanitarian and government organizations, and is already being used to inform agricultural decision making at the national scale. The GEOGLAM CM4EW provides an important advance in the use of EO for food security. This initiative has helped to raise the awareness of and demand for Earth observations in support of crop monitoring and food security decisions.  With early warning of production shortfalls and increased reliability of crop-growing condition and status, actions can be taken by government and humanitarian organizations to trigger relief response mechanisms in advance of serious food security concerns.

This post was written by Christina Justice, Inbal Becker-Reshef and Brian Barker of NASA Harvest's University of Maryland Hub and Chris Funk, a NASA Harvest partner from the University of California, Santa Barabra, and was originally posted on Feed the Future's Agrilinks Blog for this month's theme of Earth Observations for Food Security and Agriculture

News Date
May 9, 2019