Summer 2012 - a tough time for the province's crops

Saturday, November 3, 2012

Throughout the south, central and eastern regions, a long dry period during the first half of the summer seriously affected regional yields of forage crops and stunted corn crops. But the drought took an even higher toll south of the border

by HENRY HENGEVELD

This past summer in Ontario has been a cottager's dream – warm, dry, lots of sun!   

Not so for many of Ontario's farmers. The high-degree days and sunshine have, of course, been a boon. However, between the damaging frosts in mid-spring that killed off most of the fruit tree blossoms in southern Ontario and the relatively scarce and spotty rain during both spring and summer, crops across much of the province have been hit hard. As farmers know only too well, drought trumps heat.

While few climatological records were broken, the summer was unusually hot and dry.  Temperatures during June, July and August averaged about 1.5 to 2 C above normal for most areas, with Toronto's Pearson airport topping out at 3.5 C above.

Most climate and weather stations in the prime crop-growing regions also recorded between 20 and 30 days with maximum temperatures reaching 30 C or higher. Windsor, for example, registered 29 such days, while London experienced 33, Ottawa 28 and Toronto 23. However, for most regions, this was still well below the records set in 2005, when Windsor recorded 45 such hot days and Toronto 37.  

The big challenge this summer was the lack, spottiness and timeliness of rainfall. Total rainfall for June, July and August in much of the Windsor to London corridor, for example, was 45 to 50 per cent below normal. Total summer rainfall for eastern Ontario was a bit closer to normal – from about 35 per cent below normal in the Ottawa area to slightly above normal in Peterborough.

However, throughout the south, central and eastern regions, a long dry period during the first half of the summer seriously affected regional yields of forage crops and stunted corn crops. From mid-June to the end of July, Ottawa received only 30.1 millimetres, primarily from light rain showers, while Kingston received about 35 millimetres.  Hamilton got only 45 millimetres and London 59.

The impact of the early summer drought on crops was particularly severe in eastern Ontario. By early August, news media reported that most municipalities in the region had issued fire bans and warnings. Corn fields were shrivelling up, with yields in some areas projected to be about 25 per cent of normal.

Soybean and wheat crops were also suffering. Dairy and beef farmers were being forced to feed just-harvested hay to cattle to compensate for lack of forage.

The drought has also had its impact on water levels of lakes and rivers. While the Great Lakes were nowhere near the record lows of the 1930s and the 1960s, average levels of Lake Huron in August were about 59 centimetres below the long-term mean, while average levels of the St. Lawrence River at Montreal were about 112 centimetres below average, a new record exceeding that set in 2001 by eight centimetres.   

Ontario's drought problems, however, pale compared to those south of the border, particularly in the U.S. Midwest. By the end of August, almost two-thirds of all the contiguous U.S. states were in the grips of a prolonged drought, with several states in the Northwest experiencing the driest, hottest summer on record.

The 2012 American drought is estimated to be the most severe drought in some 55 years. Late summer reports on related impacts on crops suggest that 85 per cent of the U.S. corn crop, 83 per cent of the soybean crop, 65 per cent of the hay crop and 71 per cent of the cattle production area were being affected. Even more sobering, nearly half the U.S. corn and soybean crops were undergoing "extreme and exceptional" drought. Low water levels in ponds and rivers are also having significant economic impact. For example, in mid-August, a stretch of the Mississippi River was closed to barges because of the low water levels.

At the end of August, Environment Canada released its updated forecast for the fall of 2012. If its prognosis is correct, Ontario will be in for more of the same – above normal temperatures and normal to below-normal precipitation across the province (as well as for most of the rest of Canada).  

We shall see! BF

Henry Hengeveld is a retired climatologist.