The historic US drought that has, for more than a half a year, plagued so much of the nation continues to gobble up more land. Last week, drought covered 64.8% of the US. This week saw an expansion of moderate to exceptional conditions growing to cover 65.5% of the US land mass.
This is the largest land area covered by drought since the Drought Monitor began keeping records.
Though some areas in the east received rains, causing conditions to moderate there, monsoonal flows have shut down for the west, cutting off a supply of needed moisture. The loss of monsoons has resulted in the west slipping back to a hotter and drier than normal pattern, intensifying already dangerous drought conditions there.
Overall, 6.12 percent of the US suffered under exceptional drought, 21.48 percent of the US suffered under extreme or exceptional drought, 42.12 percent of the US suffered under severe or worse conditions, and 65.45% of the US suffered from moderate or worse conditions. For the week, drought area expanded in all categories.
The drought’s severe impacts to US river flows has continued to impair traffic on the Mississippi. Recently, traffic was halted near Granite City and at the Port of Osceola. At Osceola a dredge is currently laboring to re-open an area that has been closed for nearly a month due to low water. Traffic at Granite City backed up after Lock 27 suffered damage even as the low and narrow nearby river struggled to support a backlog of barges waiting for passage.
Impacts to US farmers for this year are mostly finished. However, the persistent drought raises worries for next year. Some farmers are rushing to implement the use of new heat resistant varieties of corn while others are looking to what impacts will result from this year’s losses. A few shortages have popped up on the radar screen for next year. Most notably, it appears that the world will suffer a shortage of bacon come 2013. And though grain and cereal supplies are quite low due to droughts in the US, parts of Europe, and parts of Russia, an overall shortage has yet to materialize.
Two factors are currently driving the ongoing drought in the US. The first is a long-term trend of heating and drying resulting from human caused global warming. The second is the fact that El Nino, long predicted for late 2012 to 2013, is starting to look rather weak. The most recent sea surface temperature anomaly measurements from NOAA show ENSO in a neutral to slightly positive state. This means that El Nino in the eastern Pacific, a powerful driver of weather patterns, is currently very weak. Though the World Meteorological Organization is still calling for El Nino conditions to begin within the next month, others doubt whether this El Nino will eventually form.
A weak or neutral El Nino for 2013 is not likely to provide the impetus to drive out the current US drought. So with the increasing force of global warming and a failure of El Nino to provide more consistent winter storms for the US, it appears more likely that drought will persist. This forecast seems to have been validated by the most recent seasonal drought outlook which calls for expanding drought conditions through December 31rst of 2012. Such a scenario would point toward a potential for worsening US drought conditions in 2013.