Weston Anderson181844_2063125096392_1384624282_n 

I study the dynamics of drought and its implications for agriculture and food security using remote sensing observations and model simulations. I am currently a PhD student at Columbia University in the Department of Earth and Environmental Sciences. For more information on my professional activities and my research see my Publications pageGoogle Scholar, or download my CV.


PhD student | Ocean & Climate Physics
Lamont Doherty Earth Observatory
Columbia University

weston [at] ldeo.columbia.edu


.

Recent Research

 

Fig3Life cycles of agriculturally-relevant ENSO teleconnections in North and South America (pdf)

The El Niño Southern Oscillation (ENSO) has proven to be a major driver of global crop yield variability, at times responsible for simultaneous crop failures in multiple countries. However, the temperature and precipitation teleconnections attributable to ENSO are systematic, and therefore present an opportunity to improve planning at large scales. Here we analyze how multi-year ENSO life-cycles lead to correlated risks for major crop-producing countries in North and South America.

 

 

 

 

 

AMENSO_ylds_CorrCrop production variability in North and South America forced by life-cycles of the El Niño Southern Oscillation (pdf)  

In this analysis we show how globally coherent teleconnections from ENSO life-cycles lead to correlated crop production anomalies in North and South America. We estimate the magnitude of ENSO-induced Pan-American production anomalies to be ~72, 30 and 57% of maize, soy and wheat production variability, respectively. Finally, we discuss how increasing crop harvesting frequency may increase Pan-American production variability, which we demonstrate has occurred in regions of Brazil that have shifted to a safrinha cropping cycle.

 

 


Screen Shot 2017-02-05 at 4.10.45 PMTowards an integrated soil moisture drought monitor for East Africa
 
(posterpdf) – Drought in East Africa is a recurring phenomenon with significant humanitarian impacts. Given the steep climatic gradients, topographic contrasts and general data scarcity that characterizes the region, there is a need for spatially distributed, remotely derived monitoring systems to inform national and international drought response. In this analysis we apply a suite of remote monitoring techniques to characterize the temporal and spatial evolution of the2010–2011 Horn of Africa drought.

 

 

 

.

Recent Posts

On ENSO and the timing of food shortages

Much has been written about how the El Niño Southern Oscillation (ENSO) affects temperature and precipitation globally (these impacts are often referred to as ENSO teleconnections). In two recent studies (one on climate teleconnections, one on their impacts on crop production), my coauthors and I try to bring attention to the predictable interannual evolution of ENSO, which is often overlooked in discussions of food security although not in the climate science or climate forecasting communities. In particular we look to highlight the fact that ENSO events follow a predictable pattern in which La Niñas (cold ENSO events) only occur following El Niños, and often persist for two years. While not all El Niños develop into La Niñas, the pattern is still noteworthy, particularly when one considers the implication of La Niñas for food security in North and South America.

Here we need to be precise about a few terms. I’m going to talk about three main concepts: 1.ENSO creates global teleconnections, which means that the risks posed by ENSO are correlated in space, 2. ENSO has a characteristic multi-year evolution, which means risks posed by ENSO are correlated in time, and 3.The sign and timing of the anomalies (i.e. do good years follow bad or vice versa) are critical for food security.

So to save you some time (you are after all reading this blog post rather than the paper) I’ll skip to our conclusions. 1.ENSO poses a correlated risk across much of North and South America. This means that plentiful harvests in North America tend to coincide with good harvests in major producing regions of South America (some notable exceptions mentioned in the paper). 2.The characteristic multi-year evolution of ENSO is apparent not only in patterns of temperature and precipitation, but also in yield anomalies. While not all states are influenced by ENSO in the Americas, many of the major production areas for wheat, maize and soybeans are. And in significant portions of these major production areas there is a multi-year progression of yield anomalies attributable to ENSO. 3. El Niños bring favorable growing conditions while La Niñas increase the probability of crop failures. This point is crucial when we reconnect it to the life-cycle of ENSO (i.e. La Niñas only occur following El Niños). In other words, despite the spatial correlation in the risk (remember the global teleconnections), the temporal correlation brings a silver lining: Poor Pan-American production years are likely to occur following years of above expected production. I don’t think I need to hammer home why this is positive from the perspective of food stocks and food security.

So that’s the new analysis. Some reason to worry (largely ignored correlations in the risks posed by ENSO) and some information that may be used to improve food security. There’s obviously much more in the paper, including the importance of soil moisture for each crop, so I encourage you to give them a read!

  1. Cartography of Global Cropping Systems Leave a reply
  2. How (and whether) to Disseminate Climate Forecasts 1 Reply