February 27, 2012
Farmers in Southern Brazil Hoping for Rapid Decline of La Nina
Farmers in southern Brazil continue to suffer through a dismal summer growing season. Hot and dry weather since November has resulted in severe reductions in corn and soybean yields in southern Brazil. Farmers are now hoping for improved conditions over the next several months for their safrinha corn crop and their winter wheat crop.
A key to improved weather in southern Brazil could be how fast the atmosphere transitions away from La Nina. La Nina conditions generally result in less than normal rainfall in southern Brazil, whereas El Nino conditions generally results in above normal precipitation in southern Brazil. The current La Nina is weakening, but there is no grantee that a transition to El Nino will occur in time for the safrinha corn and winter wheat crops.
Approximately one third of the safrinha corn has been planted in southern Brazil and the remainder will be planted before the end of March. The corn crop is going to need well distributed rains until the end of May to insure adequate moisture for pollination and grain filling. The wheat in southern Brazil is usually planted during April and May and while wheat does not require as much rainfall as corn, it still will need rainfall during June-July-August to insure acceptable yields. Additionally, any occurrence of freezing temperatures would be detrimental for both crops.
La Nina conditions generally results in extreme temperatures in southern Brazil, both high temperature during the summer months and low temperatures during the fall and winter months. A frost or freeze is most likely to impact the corn crop in Parana between late-May and early July. That is exactly what happened at the end of June in 2011 when a killing frost severely impacted the safrinha corn crop in Parana before it had completed the grain filling period.
If the atmosphere transitions to a neutral position or El Nino by May or June, then there will probably be a lower probability of freezing temperatures. If La Nina slowly fades, but is still in place by May, there is a possibility of cold weather in southern Brazil late in May and into June.
A humid fall in southern Brazil becomes more and more important as farmers plant larger acreages of safrinha corn. In the state of Parana, the Department of Rural Economics (Deral) is estimating that farmers will pant 1.9 million hectares of safrinha corn in 2011/12, which would be a 12% increase over last year. The safrinha corn acreage is now double the amount of full-season corn that was planted at the start of the growing season.
Therefore, this vitally important crop for the livestock industry in southern Brazil is being grown as safrinha corn, which is a risky proposition. The 2010/11 safrinha corn yields in Parana was only 3,800 kg/ha or 58.5 bu/ac.