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07/29/2018, 3:41 pm EDT

A look at Non-ENSO SSTA Regions on Global Crops

Discussion: AG traders are very aware of the prevailing change in climate influences on crops caused by the El Nino southern oscillation (ENSO). In the climate change era there is steadily growing evidence that large regions of cool/water ocean surface are affecting climate as much if not more so than ENSO. Fig. 1: Daily global SSTA analysis reveals non-ENSO related warm/cool regions causing nearby adverse climate conditions affecting crop areas. Analysis: ¬†Widespread warmer-than-normal ocean surface is observed across the middle latitudes of all oceans in the northern hemisphere. Included is the Mediterranean Sea and Great Lakes region plus Hudson/James Bay. During recent years in both the northern and southern hemispheres warmer-than-normal ocean surface in the middle-to-subtropical latitudes has evolved mid-to-late warm season. The likely cause is anomalous high pressure ridging in the upper atmosphere. Beneath these upper air high pressure ridge areas anomalous dry and hot climate develops leading to many environmental hostilities including crop damage and sharp increase in fire risk. Across or downwind of warm sea surface temperature anomaly regions in the northern hemisphere during ongoing summer harsh drought and record heat coupled with crop damage and incidence of fire events has affected Europe¬† to Western Russia, China to Japan and the U.S. to Canada. Conversely, cool pools are less abundant but sufficiently present to have a profound influence on climate. The cool pool south of Greenland related to ice melt from the Greenland ice sheet and possible change in the long-term cycle of the global thermohaline ocean conveyor belt is historically intense. This condition developed last spring and the anomalous cool water invited a lengthy presence of the wintertime polar vortex into early summer. Upstream from the polar vortex an amplified ridge formed bring record late spring/early summer heat to the U.S. while downstream Europe has encountered unrelenting heat and dryness beneath an upper ridge. Meanwhile, in the North Atlantic tropics the SSTA patterns are the coolest on record for July. As a result there is an absolute lack of any cloudiness in the North Atlantic tropics just a few days prior to the onset of the most active part of the tropical cyclone season. The cool tropical North Atlantic almost guarantees lack of hurricanes forming in the deep tropics in 2018. What activity does occur is almost certainly likely to form in the Gulf of Mexico or subtropics. A large mass of cooler-than-normal water has evolved the past 30 days east of Brazil. The cool water zone is located where prevailing easterly flow brings possible rainfall to Brazil. The cool water indicates less than normal available moisture in the lower atmosphere implying dryness for Brazil. The upper trough also correlates to a more active showery and cool pattern for Argentina.  
07/19/2018, 4:38 pm EDT

AG Global Alert: Comparing CIC & IRI 90-Day Outlooks