How does climate change affect food security? – Production

Read this very, very, short introduction first (not boring I promise but super important).
Imagine you’re a maize farmer from Iowa or Illinois. On any given day, would you think about how your actions have a critical effect on the livelihood of millions of people in developing countries? Yeah, me neither. That’s why when I read this article, the foundation for this post, I couldn’t believe how many people depend on maize yields produced in the U.S. and what happens when maize is not delivered.
At some point in your life you’ve probably seen a plant wilt and die from either lack of water or too much of it. Climate change is expected to increase the frequency of extreme weather events, that includes both those things: too much water (floods) or too little (drought). Since 96% of our food is directly or indirectly derived from soil, drought and floods mean trouble for food production.
How does climate change affect food security? – Production
(Read introduction to series here)
Case: Drought in the U.S. ‘corn belt’ – 2012

a) Extreme weather event
March to April (2012), was classified as the warmest and seventh driest maize growing season in the U.S. ‘Primary Corn Belt – a region prominently dedicated to the intensive cultivation of this crop. According to NOAA, this dry and warm combination led to declaring 89.3% of this agricultural region as suffering from moderate to severe drought (little rain and high temperatures) in September 2012.
b) Direct and indirect consequences (Gbegbelegbe, Chung, Shiferaw, Msangi, & Tesfaye, 2014)
The 2012 drought in the U.S. agricultural maize region led to a reduction of maize yields of 97 million metric tons (m.m.t.)

The U.S. is the world’s largest supplier of maize exports responsible for 72% of global exports, however, these yields typically correspond to surplus. What does surplus mean? It means the U.S. satisfies their own demand for maize first and then sells what is left to the rest of the world. The drought barely affected U.S. internal maize consumption since most of the production stayed in the country, the 2012 losses meant a 5% reduction from what the U.S. usually uses.In numbers, the usual (trend) production compared with the actual one because of the drought. We’re not saying that the 2012 drought meant nothing for the U.S., it did, but the ripple effects for the rest of the world that depends on these maize exports were very powerful.77.8 m.m.t. less U.S. maize exports for the rest of the world in 2012 Here comes the critical question: who was expecting those 77.8 million metric tons of U.S. missing maize? Where were they suppose to go and what happened when they didn’t arrive?
(Spoiler: developing countries and millions of people at risk of hunger)
c) Impact on food security (Gbegbelegbe, Chung, Shiferaw, Msangi, & Tesfaye, 2014)
The consequences of this maize scarcity were surprising to me because they reached millions of people in places far from the U.S. Corn Belt region. East and South East Asia suffered the largest decrease in volume (19 m.m.t.). But! the largest relative decrease (this means compared to the levels without the drought) was in Sub Saharan Africa by 9% (4.8 m.m.t.) – uh oh.
If you remember, the U.S. was affected by 5%, only 0.3% of that was meant to go to food, the rest would have gone to animal feed or other uses. In contrast, 10% of the missing 4.8. million metric tons of maize in Africa, were for food. In Latin America and the Caribbean, there was also a pretty significant relative reduction of food: 7% which represents 1.8 m.m.t.
When these percentages are applied to the populations from these regions, we’re talking about millions of people at risk of hunger because of an extreme weather event associated to climate change.This graph shows the food security consequences of the 2012 U.S. drought that led to reduced global maize exports. Click on the graph to access the source. SSA – Sub-Saharan Africa; LAC – Latin American and Caribbean;  EA & SE Asia – East & South East Asia; ROW – Rest of the world; CWANA – Central and West Asia and North Africa So, how does climate change affect food security? Well, in this case we saw that an extreme weather event (drought) in a region that produces 72% of global maize exports leads to missing yields that put 17 million people in Sub-Saharan Africa at risk of hunger and 2.6 million people in the Latin America and Caribbean region.
d)  Lessons learned
There are two important factors that contribute to how many people become at risk of hunger in the face of agricultural scarcity that we can take from this case:
1. The number of people that depend on the affected crop and to what extent. In this case, how many people eat maize and how much of their daily caloric intake comes from this plant.
2. The capacity to substitute the missing calories. In this example, how easy or hard was it to access other foods like cassava, wheat and rice, in the context of maize scarcity.
The risk associated to these factors can be reduced in part by diversifying calorie sources: different foods from different places.  By depending on more than one producer, Brasil and Argentina also export large volumes of maize, risk can me mitigated. By getting calories from other types of crops: barley, wheat, cassava, rice, quinoa, the likelihood of having millions of people at risk of hunger because of one single incident, can also be lowered.
This post was based on this great paper that I’ve been able to talk about freely because it’s under a Creative Commons Attribution License! Woot!
I’d like to know what foods do you eat to get most of your calories?  Feel free to comment in the section below.

Read more from the series:

How does climate change affect food security?:How does climate change affect food security? – Challenge accepted

How does climate change affect food security? – Food processing

How does food security happen? Alternative title: deconstructing a bowl of porridge