Brochures

El Niño: Canadian Perspective

• What is El Niño?
• How did El Niño 1997-98 compare with previous El Niños?
• What did El Niño 1997-98 bring to Canada?
• What are El Niños global impacts?
• Is there a link between climate change and El Niño?
• Quick facts

During the 1997-98 period Environment Canada scientists tracked the strongest El Niño in a century and a half - and for most of that winter Canadians found respite from winter cold and a reduction in home heating costs.

El Niño disrupted weather patterns in many regions of the world and was usually blamed for droughts, torrential rains, sweltering heat and severe crop failures. Scientists called the 1997-98 El Niño "the climate event of the century."

In Canada, southern regions experienced a warmer winter with less rain and snow than usual, while the extreme northeast region had below normal winter temperatures.

What is El Niño?

El Niño is a warming of waters in the eastern Pacific Ocean near the equator, thought to be caused by changes in the normal patterns of trade wind circulation.

Normally, these winds move westward, carrying warm surface waters to Indonesia and Australia and allowing cooler waters to upwell along the South American coast. For reasons not yet fully understood, these trade winds can sometimes be reduced, or even reversed. This moves warmer waters toward the coast of South America and raises water temperatures.

Warmer water causes heat and moisture to rise from the ocean off the coasts of Ecuador and Peru. The result is more frequent storms and torrential rainfall over these normally arid countries. The added heat also strengthens and alters the path of the jet stream, affecting weather patterns worldwide. In North America, this typically means the jet stream splits in the North Pacific, diverting storms toward the Yukon and Northwest Territories, while leaving most of Southern Canada with a milder and drier-than-normal winter.

How did El Niño 1997-98 compare with previous El Niños?

During the fall of 1997 El Niño showed signs of being the strongest since extensive sea surface temperature observations began in the earlier half of this century. Its strength surpassed the 1982-83 event, which at the time was dubbed "the El Niño of the century."

Surface temperatures of the Pacific Ocean off the coasts of Ecuador and Peru rose to about 5 °C above normal, the highest observed in the last 50 years. These warm waters occupied an area of about 14 million square km - about 1 1/2 times the size of Canada. At the same time, sea surface temperatures off Canada's Pacific coast averaged about 2 to 3 °C above normal. Such strong El Niño conditions presented climatologists with the best opportunity to produce

What did El Niño 1997-98 bring to Canada?

El Niño did not mean that the winter of 1997-98 was without cold, storms and blizzards. However, Environment Canada experts foresaw the likelihood of a warmer-than-usual winter - particularly from British Columbia, through Ontario, to Southern and Central Québec. The B.C. interior through the Prairies (except Manitoba) and into the Great Lakes basin had drier-than-normal conditions. Other effects were:

• Reduced amounts of rain and snowfall, combined with higher temperatures, brought lower home heating bills for most of Canada. The extreme East Arctic was colder than normal.
  
  
• Winnipeg recorded its second warmest December in 120 years. In Edmonton, El Niño-related warmth also helped to produce a record mean December temperature of 2.4 °C.
  
  
• Precipitation on the prairies was well below normal, as most grain-growing and central regions received one-half to one-quarter their normal amounts during November and December.
  
  
• Fanned by strong winds, a mid-December grass fire of Southern Alberta in the Porcupine Hills raged out of control across the parched prairie, burning more than 200 square kilometres of farmland and six houses, destroying 100 head of cattle, and burning hundreds of kilometres of fencing and winter hay supplies for many farmers.
  
  
• A record warm February helped to produce the warmest 1997-98 winter in 66 years in Southern Ontario. With temperatures 6 °C above normal, February 1998 was the warmest in over 100 years of record keeping across Southern Ontario. The city of Toronto had the warmest February on record since 1840. The lack of snow during the month was unprecedented; areas east of the Ottawa Valley remained virtually snow-free throughout most of February.
  
  
• Because of the mild December, the ice wine industry reported losses in the
  $10-$15 million range.
  
  
• Canada's worst ice storm hit central and eastern portions of the country during the first week of January, bringing 6 continuous days of freezing rain that totaled 90 mm. Trees snapped, hydro poles and wires went down and transportation from Eastern Ontario to Prince Edward Island was halted. Although ice storms in Eastern Canada are not frequent during El Niño winters, it is believed El Niño played a significant role in setting the stage for prolonged periods of freezing rain.

Departure from normal of winter
(December 1997, January 1998 and February 1998) temperature in degree Celsius.

The map shows winter temperatures during the 1997-98 El Niño winter were considerably warmer than normal throughout most of Canada. Below-normal temperatures were observed in the extreme northeast.

What are El Niños global impacts?

El Niños alter weather patterns around the world, causing abnormally high rainfall in areas that normally do not see much rain, and drought in areas that are accustomed to more precipitation. The previous strongest El Niño, in 1982-83, had dramatic effects around the world, including Australia's worst drought in 200 years. Overall, it was responsible for more than $18 billion in economic damages and 2,000 deaths.

The effects of El Niño are more direct and dramatic in the tropics. Some global impacts of
El Niño 1997-98 included:

• Severe drought in some areas of Indonesia as the dry summer season arrived early. This contributed to extreme forest fires that blanketed South East Asia in smoke and haze.
  
  
• Severe storms in central Chile in June, July and August, with rainfall totaling 10 times the normal amount for an entire year. Santiago, the capital, received more than a year's worth of rain (300 mm) in June.
  
  
• The worst drought in 50 years for Papua New Guinea.
  
  
• Crop and livestock losses exceeding $130 million in New Zealand because of dry weather.
  
  
• Sweltering summer heat in areas of Asia, from the Indian subcontinent to China, including the most severe heat wave this century.
  
  
• Unpredictable monsoons in Pakistan and Northwestern India, with spotty rain in some areas and torrential rain in others.
  
  
• Much higher than normal winter rainfall for the Southern United States, producing flooding in California and Texas, and wetter weather in Florida.

Is there a link between climate change and El Niño?

Scientists are questioning whether climate change influences changes in climate associated with
El Niño or La Niña. There is no consensus yet on any direct link. However, scientists are pursuing further research in order to provide confident answers to these questions.

Quick facts

• The phrase "El Niño" refers to the Christ Child and was coined by fishermen along the coasts of Ecuador and Peru to describe the warm ocean current that typically appeared around Christmas time and lasted for several months
• El Niño is the second largest driver of the world's weather, second only to normal seasonal warming and cooling, which also brings changes in precipitation patterns.
• El Niños appear approximately every two to seven years. They typically last 12 to 18 months. In the early 1990s a protracted El Niño persisted for four years.
• El Niños have been documented since the early 1700s. More detailed observations from ships led to instrumental record keeping in the earlier half of this century. It is only since the 1970s, however, that scientists began linking El Niño to massive flooding and severe droughts around the world.
• About every four to five years, a pool of cooler-than-normal water develops off South America. The effects of this cooler water are called La Niña. This usually brings colder winters to the Canadian West and Alaska and drier, warmer weather to the American Southeast.

For Further Information

Amir Shabbar
Environment Canada
(416) 739-4435

David Phillips
Environment Canada
(416) 739-4316

El Niño Web site: http://www.tor.ec.gc.ca/elnino/

The Green Lane^TM,
Environment Canada's World Wide Web Site.