South America: Widespread exceptional water deficits for much of Brazil

22 June 2017

The Big Picture
Water deficits are forecast for much of the northern half of South America through February 2018, as shown in the 12-month map (below). Exceptional deficits are expected in large pockets and along major rivers in Brazil, northern Chile, the Gulf of Corcovado, and Tierra del Fuego.

Exceptional surpluses are forecast for Mendoza, La Pampa, and Buenos Aries Provinces in Argentina; and, the border area between Argentina, Paraguay and Brazil.

Impacts
In late May heavy rainfall caused flooding in Pernambuco and Alagoas, Brazil, resulting in 7 deaths and the evacuation of 40,000 people, and swelled water levels at Mundaú Dam from 40 percent to 83 percent. Flooding also affected 3,500 people in Uruguay and 1,000 in Paraguay, and resulted in losses in Paraguay's safrinha soybean harvest and low seed quality for next season's planting.

But despite the recent rainfall, much of Brazil's northern extent remains in water deficit conditions. The situation in the Northeast is particularly critical, with reservoirs at 18.55 percent of capacity, as reported on June 21, 2017 by Operador Nacional do Sistema Elétrico (ONS - Brazil's national grid operator). Jucazinho Reservoir - the main source of water for 15 municipalities in Pernambuco - remains completely dry, as it has been since September 2016.

Drought, federal policy, and corruption in Brazil are changing the national profile of the country's electricity sector. The 2013-2015 drought negatively affected hydroelectric production, forcing power companies to purchase natural gas from Bolivia to operate thermoelectric facilities. The resulting debt burden - along with other economic factors - has spurred asset-shedding, creating bargain opportunities for Chinese investors.

Chilean vineyard owners are still accessing damages from wildfires earlier this year that raged through the Central Valley's wine-producing region. Hot, dry conditions in late January fueled fires that destroyed 400,000 acres of forests and damaged 100 vineyards. Some vineyards are reporting a 40 to 50 percent decline in the 2017 harvest due to the fire, but are as concerned about persistent drought that reduced yields last year by 20 to 30 percent for some and continues to threaten the Chilean wine industry's comparatively lower price point in the global market.

Forecast Breakdown
The 3-month maps (below) for the same 12-month period show the evolving conditions in greater detail.

The forecast map for June through August is similar to the map of observed conditions for the prior three months. Similarities include widespread deficits in Brazil, including large pockets of exceptional deficits in Acre, Rondônia, Pará, Tocantins, Mato Grosso, Goiás, Minas Gerais, and São Paulo. Deficits are also expected along many rivers including the São Francisco, Tocantins, and the Amazon and its tributaries. Exceptional deficits are expected to expand from Antofagasta, Chile northward through Huancavelica, Peru; expand in southern Chile and the Chubut River in Argentina; and, emerge in the border region between Peru and Colombia. However, exceptional deficit conditions along the Pilcomayo, and eastern portions of the Paraná will return to moderate to near normal.

In general, conditions are forecast to return to near normal from September through February. Exceptional drought in Brazil is forecast to recede from south to north and most regions with exceptional surpluses will improve to moderate surpluses. From September through November 2017, exceptional deficit conditions persist in northwestern Venezuela, northern Brazil, French Guiana, Suriname, northern Chile, and pockets along the border between Bolivia and Peru. In the December 2017 through February 2018 time period, exceptional deficits are limited to small regions in the Atacama Region of northern Chile, Roraima State in Brazil, and Apure State in Venezuela.

(It should be noted that forecast skill declines with longer lead times.)