Monday, 4 January 2016

EL NINO: a curse and a blessing                          

This weather phenomenon is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (between approximately the International Date Line and 120°W), including off the Pacific coast of South America. El Nino is accompanied by high air pressure in the western Pacific and low air pressure in the eastern part of the Pacific. El Niño Southern Oscillation refers to the cycle of warm and cold temperatures, as measured by sea surface temperatures. El Ninos form when the westward-blowing winds in the Pacific weaken or reverse direction, triggering a warming of the upper part of the Pacific Ocean. Clouds and storms follow this warm band of water, pumping heat and moisture high into the atmosphere. It has been associated with reduced rainfall in Southeast Asia, heat waves in India, droughts in South Africa, and flooding in South America and southern United States. and warming in northern United States and southeastern Canada.

Developing countries dependent upon agriculture and fishing, particularly those bordering the Pacific Ocean, are the most affected. In Spanish, the capitalized term "El Niño" refers to the Child Jesus, so named because the pool of warm water in the Pacific near South America is often at its warmest around Christmas.                                                                                                   

Measurements and simulations have found that climate change has created a tendency toward more extreme El Niños in recent years.        

El Niño Southern Oscillation  (ENSO) The U.S NOAA definition is a 3-month average warming of at least 0.5 °C (0.9 °F) in a specific area of the east-central tropical Pacific Ocean; other organizations define the term slightly differently. Typically, this anomaly happens at irregular intervals of two to seven years, and lasts nine months to two years. The average period length is five years. When this warming occurs for seven to nine months, it is classified as El Niño "conditions"; when its duration is longer, it is classified as an El Niño "episode".

When El Niño conditions last for many months, extensive ocean warming and the reduction in easterly trade winds limits upsurge of cold nutrient-rich deep water and as a direct result, the economic impact to local fishing for an international market can be serious. El Niño can also affect commodity prices and the macro-economy of different countries. It can constrain the supply of rain-driven agricultural commodities; reduce agricultural output, construction, and services activities; create food-price and generalized inflation; and may trigger social unrest in commodity-dependent poor countries that primarily rely on imported food.  

Extreme weather conditions related to the El Niño cycle correlate with changes in the incidence of epidemic diseases. For example, the El Niño cycle is associated with increased risks of some of the diseases transmitted by mosquitoes, such as malaria, dengue, and Rift Valley fever. Cycles of malaria in India, Venezuela, Brazil, and Colombia have now been linked to El Niño.

ENSO may be linked to civil conflicts. Scientists at The Earth Institute of Columbia University, having analyzed data from 1950 to 2004, suggest that ENSO may have had a role in 21% of all civil conflicts since 1950, with the risk of annual civil conflict doubling from 3% to 6% in countries affected by ENSO during El Niño years.

Because El Niño's warm pool feeds thunderstorms above, it creates increased rainfall across the east-central and eastern Pacific Ocean, including several portions of the South American west coast. The effects of El Niño in South America are direct and stronger than the effects in North America. An El Niño is associated with warm and very wet weather months in April–October along the coasts of northern Peru and Ecuador, causing major flooding whenever the event is strong or extreme. The effects during the months of February, March, and April may become critical.

Along the west coast of South America, El Niño reduces the upsurge of cold, nutrient-rich water that sustains large fish populations, which in turn sustain abundant sea birds, whose droppings support the fertilizer industry. The reduction in upwelling leads to fish kills off the shore of Peru. This is a blessing for the fishermen in that area of the Pacific.

Winters, in the Northeast and northern Midwest of the United States and in most of Canada are generally cold and we get a great deal of snow however during the El Niño period, those areas of North America and Southern Canada are warmer and drier than average resulting in those regions experiencing reduced snowfalls. In some parts of the world, including many pockets of Canada, unseasonably high winter temperatures made for a green holiday season I live in the southern part of Canada (near Toronto) and the first snow fall came on December 29th of this year whereas we generally begin getting it in the first week of December.  This is a blessing to us. Driving on roads that are not covered with snow and being able to go outside without having to bundle up like those who trek in the Artic is a definite blessing.

Meanwhile, significantly wetter winters are present in the northwest part of Mexico and the southwest part of the United States, including central and southern California. Both have cooler and wetter than average winters in northeast Mexico and the Southeastern United States (including the Tidewater region of Virginia) occurring during the El Niño phase of the oscillation. Hence, there is a great deal of flooding in the southeastern part of the United States.

Tornadoes in Texas along with flooding in Southeastern and Northern mid United States to unseasonably warm temperatures in Canada and Europe, to brushfires in coastal California and Australia—this spate of wacky late-December weather has been one for the history books. Damage to homes and buildings after a tornado hit Garland, Texas, on Dec. 27, 2015 killed at least 11 people and dozens more were injured in tornadoes that swept through the Dallas area. Nearly all of Interstate 40 in Texas, the main east-west highway through the Texas Panhandle, was closed due to the snowstorm pummeling the area.

The extreme weather is being blamed, at least in part, on El Nino. In the United States the severe weather events caused more than 40 deaths in the United States that followed Christmas of 2015. 

Wind-blown waves from Lake Michigan broke around the Shedd Aquarium as a winter storm moved across Illinois on Monday, December 28, 2015, in Chicago, bringing high winds, icy precipitation and waves up to 7 metres (21 feet) high along the shores of that great lake.

Flooding in England, Scotland and Wales plunged parts of the U.K. underwater, particularly northern parts of England, such as York, where the River Ouse was running more than five metres above normal summertime levels. More than 500 soldiers were dispatched to Yorkshire and Lancashire to assist in rescue efforts, according to the BBC.

Flooding in the area where the borders of Paraguay, Argentina and Uruguay meet forced nearly 150,000 people to flee their homes in the last week of December 20o15. El Nino has brought the torrential rains to the area, causing levees to fail and fast-moving water of water to overflow.

The current El Nino weather episode that's causing some of the wild weather seen around the world this year shows no signs of waning, according to NASA. Superstorms, flooding and freaky weather as predicted are becoming a reality. NASA has stated that the full effects of El Nino may not be felt in North America and South America until early 2016, warning that we may not have seen the "peak" of the still-growing weather phenomenon.  This current El Nino has "earned its stripes," dubbing it as the "Godzilla of El Ninos." What will the next one be called?

Is what we are currently experiencing weather-wise because of El Nino and if so, is it really because of global warming? If so, it’s not too late to reduce the effects of El Nino.

No comments: