Tuesday, 3 April 2018

Natural Disasters and Family Misfortunes 13: 1789-93 El Niño Event

El Niño events have been more studied in recent decades as their regularity and disruptive character has devastated areas around the globe. Such events are new or restricted to modern times but have been part of the Earth’s climate history for many millennia – at least. The most recently reported-on El Niño years are 1997-98 and 2015-16 when temperatures soared, droughts were widespread and calamitous weather was experienced. Readers will find many reports of the damage wrought by these two storms online and in news accounts.

The history of many regions is being re-examined with respect to El Niño and La Niña events, specifically, to see whether these weather conditions played a negative or positive role in their exploration, settlement or development.

As described on the Live Science website, “El Niño is a climate cycle in the Pacific Ocean with a global impact on weather patterns. The cycle begins when warm water in the western tropical Pacific Ocean shifts eastward along the equator toward the coast of South America. Normally, this warm water pools near Indonesia and the Philippines. During an El Niño, the Pacific's warmest surface waters sit offshore of northwestern South America. . . There is also an opposite of an El Niño, called La Niña. This refers to times when waters of the tropical eastern Pacific are colder than normal and trade winds blow more strongly than usual. Collectively, El Niño and La Niña are parts of an oscillation in the ocean-atmosphere system called the El Niño-Southern Oscillation, or ENSO cycle, which also has a neutral phase.”

More detail about El Niño and La Niña, along with pertinent references can be found at the end of this post.

Prior to the 18th century, there was little documentation for El Niño events, at least is defining them as such. Many regions certainly suffered droughts or exceptional rainfall in similar patterns to what we recognize as El Niños today, so there seems to be no doubt these extreme weather conditions did operate and had severely impacts on communities.

One major El Niño event that affected most parts of the civilized and developing world, perhaps serving as a great example of how ancestral communities and families were affected, occurred during the Northern Hemisphere winter of 1791-92. This was in the late part of the Little Ice Age, a time when most settled areas had already undergone deprivation with cold, drought, famine and disease for many decades. Such events will have exacerbated the harsh living conditions extant during this time period.

An article by Richard H. Grove (2007) describes the effects of the extended 1789-93 El Niño in areas around the globe very succinctly for the regions of:
·         Australia (drought, rivers dried up, crop failures)
·         Brazil (drought, cattle industry disseminated)
·         Caribbean Islands (drought)
·         Chile (drought)
·         East Indies and South Pacific (cold and drought)
·         Eastern North America (high temperatures, heavy rainfall, leading to rise in mosquito population and spread of diseases like yellow fever)
·         Egypt (low floods in successive years, poor crops, famine, social unrest)
·         England (unusually high winter temperatures)
·         France and Western Europe (unusual and extreme weather possibly resulting in the social unrest that was part of the French Revolution)
·         India (see below)
·         Mexico (drought, major lake levels dropped)
·         Peru (exceptional and prolonged rainfall, flooding)
·         Russia (drought)
·         South Africa (drought, military conflict with migrating people)
·         Southwest USA (excessive rain, flooding, cropland and infrastructure destruction)

India was among the regions hardest hit. The widespread drought over several years created famine almost unprecedented even for that country. In many regions, communities lost half of their populations to starvation and associated epidemics. The famine was so intense that bodies remained unburied creating a spectre of rotting corpses along roadways and in fields. The abundance of bleaching bones resulted in the famine being called Doji bara, or the skull famine. Cases of cannibalism were reported. Millions are reported to have died between 1789 and 1792.
Map of India (1795) shows the Northern Circars, Hyderabad (Nizam), Southern Maratha Kingdom, Gujarat, and Marwar (Southern Rajputana), all affected by the Doji bara famine (retrieved 3 April 2018 from Doji bara famine Wikipedia)

And the list goes on! Many areas hit were newly-established colonies such as those in Australia, India and South Africa or developing communities such as those in North America.

Family historians my find, on closer examination, that El Niños were perhaps responsible for problem their ancestors may have had in food production or other employment. Such events may possibly have been behind their reason to migrate to areas where they thought a better life and more opportunity might be found. Whether they found those improved living conditions might well have depended on the weather or climatic conditions in their new homes.

How El Niños and La Niñas work

Understanding how El Niños and La Niñas work will give a family historian a better idea of whether their ancestors might have been affected in their normal lives or following migration to new regions. The following descriptions are taken from El Niño: The weather phenomenon that changed the world by Ross Couper-Johnston (2000):

Typically during El Niños, rainfall is greatly reduced over much of Indonesia; the Philippines; northern and eastern Australia; the populated Pacific Islands; New Zealand’s North Island; India; southern Africa; Ethiopian highlands; Ghana; Nigeria; Sahelian Africa, most of central America extending into central Mexico, Colombia and northern South America; the Caribbean; northeast Brazil; and the Altiplano of Peru and Bolivia. Most of the major droughts in these regions have occurred during El Niños. The Sahel receives a moderately strong El Nino signal but is also markedly affected by longer-term fluctuations. On the other hand, heavier rain and increased probability of flood conditions are found over much of southern USA and the Great Basin, northern Mexico; the Peruvian and Ecuadorian coastline; central Chile; southeastern and northern Argentina; Paraguay; Uruguay and southern Brazil; the islands in the central and eastern equatorial Pacific such as the Galapagos and Nauru; New Zealand’s South Island; the very southern tip of India and Sri Lanka; central China to southern Japan; Vietnam; the western
cape of South Africa; Kenya; Tanzania; Uganda; and much of western Europe. There are many other regions such as central California and northern Europe, that experience significant impacts, although the nature of the anomalies is somewhat inconsistent
.” [page 44-45]
Trade winds during an El Niño year from Thomson Higher Education website

Broadly speaking, the pattern for La Niñas is the reverse of that of El Niños. Excessively wet or flood conditions are experienced predominantly over the continents bordering the Pacific and Indian Oceans – in particular, Australasia, northern China, India, southern Africa and parts of north-eastern South America. Dry or drought conditions tend to occur most commonly in the Gulf states of the USA, south-eastern Argentina, central Chile, central China, South Africa’s western Cape, eastern Africa and much of western Europe.

Unusually colder temperatures are commonly experienced across northern South America, the Caribbean, Alaska and north-western Canada, Japan, South-East Asia, India, southern Africa, Sahelian and north western Africa, and western Europe. North eastern Australia and central south-western Pacific tend to experience warmer conditions.

The poleward shift of the sub-tropical jet streams in La Niñas increases the probability of stronger and more frequent tornado activity in the USA in all tornado prone areas – particularly in the Ohio and Tennessee River valleys – with the exception of the Florida peninsula
One of the most dramatic Impacts of La Niña and El Niño events on people is the reshuffling of likely tropical storm formation zones. . .

During La Niñas, high pressure cells in the sub-tropical Atlantic tend to be weakened and displaced off North and South America, creating warmer waters than usual. This has the effect of extending the hurricane season. The frequency of hurricanes occurring during La Niñas is approximately double that of normal years.” [page 46-47]
Trade winds and rainfall during a normal year, from Thomson Higher Education website


Couper-Johnston, R. (2000). El Niño: The weather phenomenon that changed the world. London: Hodder and Stoughton.

Davis, M. (2001). Late Victorian Holocausts: El Niño famines and the making of the third world. London-New York: Verso.

Fagan, B. (1999). Floods, Famines, and Emperors: El Niño and the fate of civilizations. New York: Basic Books, Perseus Books Group.

Grove, R. H. (2007). The Great El Niño of 1789-93 and its Global Consequences: Reconstructing and Extreme Climate Event in World Environmental History. The Medieval History Journal, 10(1&2), pp 75-98.

Grove, R. & G. Adamson. (2017). El Niño in World History.  London: Palgrave Macmillan. (also in Kindle version)

Sandweiss, D. H. & J. Quilter. (2008). El Niño, Catastrophism, and Culture Change in Ancient America. Washington, DC: Dumbarton Oaks, Harvard University.

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