Two consecutive La Niña years have depressed world food supplies and driven commodity prices higher. Now, the US Climate Prediction Center is warning that the disruptive global weather event is likely to return for a third year, a rare occurrence that has happened only twice in the past 70 years.
La Niña conditions for a third year in a row could have far-reaching effects on global agriculture by triggering large shifts in weather. La Niña tends to create drought and dry conditions in many parts of the world, including Brazil, Argentina, and the US, while bringing additional precipitation to other areas, such as Australia.
Current dry conditions in Argentina’s northern provinces are reducing acreage planted to wheat. A continuation of La Niña could hinder the crop’s yield development in the key months of September and October. Argentina is the biggest South American producer and exporter of wheat and accounts for about 8% of global wheat exports. La Niña previously caused substantial soybean losses in Argentina during the 2020/21 and 2021/22 seasons.
Brazil corn and soybeans also could suffer from a return of La Niña in late 2022 and early 2023. A Gro analysis shows that La Niña correlates strongly with increased levels of drought and reduced corn yields in Brazil, the world’s No. 2 corn exporter.
This past year, Brazil’s southern states experienced “severe” levels of drought, as shown by the Gro Drought Index, weighted for soybean acres using Gro’s Climate Risk Navigator. Soybean yields dropped by double digits year over year, according to Gro’s Brazil Soybean Yield Forecast Model.
US hard red winter wheat (HRW), currently being harvested, also suffered from dry conditions brought on by La Niña. Amid one of the worst droughts since 2014, farmers in Kansas and Texas will abandon a substantial portion of their HRW wheat crops, Gro data shows. And Gro’s yield forecast model is pointing to a double-digit decline in HRW yields.
Australia, on the other hand, is poised for a third year of strong wheat production in 2022 as good weather boosts planting across its grain belt. While it is too early to estimate the size of the 2022/23 crop, which will be harvested at the end of the year, conditions so far are superior to last year, as shown by Gro’s Climate Risk Navigator, weighted for Australian wheat acres.
Australia produced a record 36 million tonnes of wheat in 2021/22 and was the world’s third-largest wheat exporter, shipping largely to China, Indonesia, and other Asian buyers.
New crop prospects can be monitored using Gro’s machine-learning Australia Wheat Yield Forecast Model, which will provide daily updates of yield estimates once the crop emerges from dormancy in August.
The US Climate Prediction Center’s latest forecast shows that La Niña conditions are likely to return for a third-consecutive Northern Hemisphere winter in 2023. The CPC said most climate models predict a weakening of La Niña conditions by late summer, followed by a 58%-59% chance of La Niña strengthening during the Northern Hemisphere fall and early winter. The last time La Nina was in place for three years in a row was from 1998 to 2001.
La Niña conditions are currently in place, according to the CPC’s Oceanic Niño Index, which is calculated based on ocean temperatures in a specific part of the Pacific Ocean. A separate index called the Multivariate ENSO Index, which is available on Gro's web portal, also indicates La Niña is in effect — negative values indicate La Niña conditions while positive values point to El Niño conditions. The Multivariate ENSO Index includes additional variables such as sea level pressure.