Grainews – Phil Franz-Warkentin 2/25/2009  - Winnipeg (Resource News International) — La Nina conditions in the Pacific Ocean over the winter are seen as a potential indicator of large Canadian wheat yields the following summer.

Long-term weather conditions can be an inexact science, due to the sheer number of variables involved. But La Nina and El Nino conditions, which relate to Pacific Ocean surface-level water temperatures along the equator, are often directly linked to weather patterns in South America and Australia, meteorologist Mike Tannura of Chiacgo company T-storm Weather told the Canadian Wheat Board’s annual Grain World Conference here Tuesday.

However, the Rocky Mountains make it more difficult to find direct linkages between La Nina/El Nino and weather conditions in the U.S. Midwest or Canada’s Prairies, he added.

Looking at the major North American crops over the past 50 years, Tannura attempted to find a correlation between La Nina conditions in the winter and yields the following summer. In the U.S. he could find no correlation for corn, soybeans or wheat. [more...]