Drought in Chile

Through its history Chile has been regularly affected by droughts. In the more arid parts of Chile droughts are produced when there are low amount of snow accumulation in the Andes.[1] Chilean coastal basins without snow accumulation are particularly vulnerable to drought.[1]

The territory of Central Chile has been affected by long-term droughts in 1280–1450, 1570–1650 and 1770–1820.[2]

Historical droughts

San Carlos Canal in picture begun to be built in 1772 in response to years of drought.

Drought of 1770–82

The 1770–1782 period was one of general drought in Central Chile with a total of three non-consecutive years of extreme drought.[1] In 1772 vineyards and cropfields along Mapocho River in Santiago could not be irrigated.[3] This drought led the authorities to begin the construction of the long-planned San Carlos Canal in 1772 to deviate waters from Maipo River to Mapocho River.[3]

Drought of 1924

In 1924 a drought spread between Coquimbo and Maule Region.[4] In Coquimbo Region (at the time known as Province of Coquimbo) 70% of the wheat from non-irrigated land was lost while in irrigated areas the harvest loss was of 20%.[4] The price of railroad transport of livestock to places south of Curicó was lowered by 40% as there was hardly any grass or plant buds for livestock to eat in Norte Chico.[4]

Rural people in Coquimbo Region flocked around the towns of Illapel, Combarbalá and Ovalle.[3] Later the intendant of Coquimbo claimed that about hundred people had left the province as result of the drought.[4]

Great Drought of 1968–69

The drought faced by Chile between 1968 and 1969, known as the Great Drought of 1968, was one of the largest rainfall deficits in the country during the twentieth century, only comparable to the drought of 1924.[5] The drought had its origin in the low amounts of precipitation that fell in 1967.[6] The area affected by the drought spanned from Atacama Region in the north to Ñuble Province in the south.[7]

The drought created huge losses for cultivations of potato, rice, maize, beans. Fruit trees and vineyards were also affected.[6] 100 thousand cattle and 1 million sheep died because of the drought. Milk, meat and wool output declined.[6] By September 1969 only 250 thousand goats remained from an earlier population of 650 thousand.[6]

Through rural Norte Chico many farmers and communities came to lack water even for human consumption.[6] In 1969 farmers received support of several financial institutions and state agencies including tax exemptions and a line of credit to buy forage.[6]

In Central Chile the typical river flow increase in December did not happen in 1968.[7] Chile many farmers decided to not cultivate in early summer due to this and the known fact there was almost no snow in Andes.[7] Later in summer the rivers did grew due to glacier ablation a causing many farmers to repent albeit it was too late to cultivate.[7]

The decline in hydroelectrical power generation (The hydroelectrical deficit was of 200 GW) was partly compensated by having the thermoelectrical plants of Ventanas, Renca and Laguna Verde function at maximum capacity.[6] To supply the thermoelectrical plants with coal the production and stock of Lota-Schwager was not enough and government authorized the import of 50 thousand tons of coal from the United States, Poland, France and Germany.[6]

In the hydrological year of 1969–1970 the area affected by the drought disminished from previously spanning the latitudes of 27–37° S to 27–33° S.[7]

Drought of 1998–99

Beginning in December 1996 the El Niño phenomenon affected Chile during 14 months until 1998.[8] Sea temperatures were high in the Pacific.[8]

The drought of 1998-1999 caused an energy shortage in SIC, Chile's main power grid.[9] The energy shortage was worsened by problems in the Nehuenco Power Plant driven by natural gas.[9] Annual rainfall in Zona Sur was far below previous record lows: in Valdivia only 1,033.8 millimetres or 40.70 inches fell and in Concepción just 598.6 millimetres or 23.57 inches,[10] whereas the lowest before 1996 had been 674 millimetres (26.54 in) in 1924.

References

  1. 1 2 3 Astaburuaga G., Ricardo (2004), "El agua en las zonas áridas de Chile", ARQ (in Spanish), 57: 68–73
  2. ↑ Villalba, Ricardo (1994), "Fluctuaciones climáticas en latitudes medias de América del Sur durante los últimos 1000 años: sus relaciones con la Oscilación del Sur" (PDF), Revista Chilena de Historia Natural (in Spanish), 67: 453–561
  3. 1 2 3 Urrutia & Lanza 1993, pp. 67-68.
  4. 1 2 3 4 Urrutia & Lanza 1993, pp. 201-203.
  5. ↑ Espíldora, Basilio (1972), "Algunos antecedentes hidrológicos de la sequía en Chile" (PDF), Acta del Seminario Regional sobre Hidrología de Sequías, pp. 181–184, retrieved 2011-02-14
  6. 1 2 3 4 5 6 7 8 Urrutia & Lanza 1993, pp. 337-340.
  7. 1 2 3 4 5 Lobo, Eugenio (1972), "HIDROLOGIA DE SEQUIA EN CHILE" (PDF), ACTAS DEL SEMINARIO REGIONAL SOBRE HIDROLOGIA DE SEQUIAS (Lima, 21-27 de julio de 1970) (in Spanish): 226–229
  8. 1 2 Puentes, Edgardo, El Niño y la Niña (in Spanish), retrieved July 30, 2013
  9. 1 2 Crisis de Chile (1998-1999) (in Spanish), retrieved July 30, 2013
  10. ↑ ‘Estadistica Climatologia II’

Bibliography

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