Preventing Famine with Early Warnings

Satellite networks monitor crop conditions to predict which regions will need help.

Graphic visualization of satellites monitoring crop conditions
Graphic visualization of the GEOGLAM system. Credit: “Improving Food Security Policies” session, AAAS Conference, Seattle, Washington, February 15, 2020. Photo: Anne N. Connor

In the past, it could be challenging to predict when crop failures would hit a region. Today, international groups have created early warning systems combining global satellite networks and big-data analysis.

How can an early warning help? When farmers know that locusts are coming their way, they can plan to cover their crops until the pests pass. When they know a drought is coming, they can plant more drought-tolerant crops. And governments can arrange to send food aid to areas in danger of famine.

A session on food security policies at the American Association for the Advancement of Science conference in Seattle, February 2020, described two efforts providing such early warnings.

Food Supply and Demand

The Food and Agriculture Organization (FAO) of the United Nations developed the Global Information and Early Warning System (GIEWS) to monitor agricultural conditions. The system analyzes a vast amount of data collected by satellite and other means.

GIEWS monitors and reports on food supply and demand across the world. The system issues Special Alerts if supply and demand don’t match, said Mario Zappacosta of the FAO’s Trade & Markets Division. Those interested can subscribe to those alerts by RSS feed or email.

GIEWS crunches a lot of data to feed those alerts. It combines data on weather patterns, the prices of agricultural inputs such as seeds and fertilizer, crop production, crop prices, and pest and crop disease outbreaks. It even tracks salaries in each region to see if families can afford local food. GIEWS is also developing a way to forecast where drought is likely but has not yet occurred. 

GIEWS uses satellites with high resolutions, down to 30 square-foot sections. The satellites can tell if crops are green or brown, tall or short.

GIEWS uses vegetation conditions and other data to build an indicator called the Agricultural Stress Index, which is also available in map form.

Rapid Response Reporting

Catherine Nakalembe is originally from Uganda and now works on NASA-related projects, including the GEOGLAM Crop Monitor program. GEOGLAM (GEO Global Agricultural Monitoring Initiative), based at the University of Maryland, has over 50 partners.

Nakalembe said that satellite data offer “timely, objective, and repeatable” information. Satellites allow global crop monitoring, even when times of war or conflict make it difficult to view conditions in person.

Like GIEWS, GEOGLAM can integrate satellite images with other data. GEOGLAM releases regular crop assessments and bulletins through the Agricultural Market Information System.

The NASA satellite data used by GEOGLAM goes back to the 1980s, so it’s easy to spot trends. “We have a long, dense time record,” Nakalembe said.  

GEOGLAM monitors the amount of water used in crop irrigation. Water monitoring allows GEOGLAM’s partners to reach farmers who would like to increase their water-use efficiency. Because weather data are sparse in some developing countries, GEOGLAM is developing innovative ways to collect water use data from local on-the-ground sources.

GEOGLAM offers rapid response Special Reports related to inclement storms, locusts, etc. Special Reports help countries in the path of these risk factors prepare a response.

Next Saturday

Alan Belward of the European Commission’s Joint Research Centre said that systems like GIEWS and GEOGLAM are crucial. “We’re not playing games,” he said. “This is about real people, real hunger. It’s not abstract.”

There is a lot of pressure on collaborative crop monitoring efforts to get it right. “The timescale is today—next Saturday. We’re going to act now. That puts an onus on the science that’s very high level,” said Belward.

Graphic visualization of people concerned about food systems.
Graphic visualization of global concern about food security and collaborative efforts to safeguard it. Credit: “Improving Food Security Policies” session, AAAS Conference, Seattle, Washington, February 15, 2020. Photo: Anne N. Connor

2003 NASA map of plant growth anomalies
A 2003 snapshot of Earth's plant productivity shows increased productivity (green) and decreased productivity (red). Credit: NASA Goddard Space Flight Center Scientific Visualization Studio.