Nov 3, 2014 by Jawoo Koo

"... (A) grand African paradox was beginning to form in Kenya: food shortages and surpluses side by side, simultaneous feast and famine. Drought was spreading in the northern and eastern reaches of Kenya, threatening herders and their livestock. The government declared a food shortage in the country and said it would be necessary to import food, either by purchasing from neighboring countries or inviting food aid, to feed the growing ranks of the hungry. ... At the same time, farmers in the breadbasket regions of western Kenya and the Rift Valley were complaining about the low prices they were receiving for their maize."

May 23, 2013 by Jawoo Koo

Where in sub-Saharan Africa is the difference between actual and potential yield of maize most striking? We can answer this question pixel by pixel, region by region, but for the purpose of this brief analysis, let’s talk countries.

May 22, 2012 by Jawoo Koo

While we were brainstorming “big ideas” at a recent working retreat, we stumbled upon the idea of promoting FourSquare as a tool to monitor smallholder farmers’ crop management practices.

Aug 31, 2011 by Jawoo Koo

With limited resources to cope with weather variability, smallholder farmers in Sub-Saharan Africa (SSA) are facing highly unreliable crop production from year to year. In this modeling exercise we quantified how much area is under such condition and what are their production potential under intensification. The simulation result indicates that, without further intensification, only 15% of current maize growing area has the potential to reliably produce more than 3 t/ha, a yield level suggested as being sufficient to sustain the cereal needs of a typical smallholder household. However, with well-managed intensification, 82% of the current maize area showed the potential to reliably produce 3 t/ha or more.


Feb 16, 2011 by Jawoo Koo

What's the reported level of maize yield in Chad? Or, how about for all Sub-Saharan Countries? What's the time trend of groundnut yield in Ghana? Please be quick; you have one minute to find the answers! OK, good questions.


Feb 12, 2011 by Jawoo Koo

"How to compile and run DSSAT v4.5 on Linux?" Good question.


Feb 11, 2011 by Jawoo Koo

HarvestChoice uses a so-called meso-scale spatial grid typically at 10km or 5-arc minute resolution.


Illustration by Mike Shibao, based on imagery from CMMAP.

Feb 4, 2011 by Jawoo Koo

Crop systems models can help researchers estimate the future of food security under climate scenarios. Many crop models are known to exist around the world - for different crops with varying complexities, yet it is not easy to find the right model for the right problem. To better understand the global extent of crop model development and to identify gaps in capabilities, HarvestChoice participated in an initiative to conduct a rapid meta-analysis of crop models using on-line survey to the crop modeling community in the world. Here are the key findings.

Word cloud of crops that respondents modeled

Dec 22, 2010 by Jawoo Koo

How to use the weather generator in the DSSAT Crop Systems Model for climate change studies, and what should I know? Good question.


Dec 16, 2010 by Jawoo Koo

Long-term yield trials are great resources for agricultural researches in multiple disciplines, but such dataset have not been readily available in Sub-Saharan Africa. The Hatfield Experimental Farm in Pretoria, South Africa, is an exceptional case that has been providing maize yield and fertilizer trial dataset with 32 treatments since 1939. In collaboration with University of Pretoria, HarvestChoice facilitated the re-discovery of raw yield dataset from the trial to study the measured long-term yield variability.

Long-term maize trial plots at the Hatfield Experimental Farm, U of Pretoria