Drought monitoring in the Brazilian Semiarid region

Abstract

Drought is a natural and recurrent phenomenon. It is considered 'a natural disaster' whenever it occurs in an intensive manner in highly populated regions, resulting in significant damage (material and human) and loss (socioeconomic). This paper presents the efforts developed to monitor the impact of drought in the semiarid region of Northeast Brazil. In this scope, information from different sources is compiled to support the evaluation and identification of impacted municipalities, with the main objective of supporting emergency actions to mitigate their impact. In the semiarid region of Brazil there are frequent occurrences of dry periods during the rainy season, which, depending on the intensity and duration, can cause significant damage to family-farmed crops, with a farming system characterized by low productivity indices. However, rain-fed agriculture has great economic expression and high social importance due to the region is densely occupied, and contributes to the establishment of communities in the countryside. Specifically, in the present study, the methodology adopted to monitor the impact of agricultural droughts, including an analysis of the hydrological year 2015-2016, is presented, considering different water stress indicators for the identification of the affected municipalities and assessment of the methods and tools developed.

Extreme Drought Events over Brazil from 2011 to 2019

“…Because of this, according to the Integrated Disaster Information System [78], the Federal Government recognized the emergency situation in 70% of municipalities (378 in total) in the Rio Grande do Sul State. Such recognition allows the municipalities to request the support of the Federal Government for emergency measures to face the water scarcity period [68]. Especially from 2011 to 2017, droughts affected most parts of Brazil.…”

Frequency, duration and severity of drought in the Semiarid Northeast Brazil region

“…The SNEB region (Figure 1) is periodically affected by drought. To diminish these impacts, SUDENE (Superintendence for the Development of the Northeast − Superintendência de Desenvolvimento do Nordeste) was implemented in 1970s under National Integration Ministry (Ministério da Integração Nacional − MI) to promoting sustainable development of its acting area, aggregating 1989 municipalities, including the SNEB region (Alvalá et al, 2017). The geographical location of SNEB comprises most area covered by mixed grasslands, 'caatinga' (closed and open shrublands) and savanna (Vieira et al, 2013).…”

Datasets of meteorological drought events and risks for the developing countries in Eurasia

“…Since SPI, SPEI and scPDSI are separately calculated based on precipitation alone, precipitation and PET, and water supply and demand using a water-budget model, respectively, some divergences between them are expected. Because any single index is not sufficient for precisely identifying drought events and examining drought characteristics, the combined use of different indices may better represent the actual drought condition and its variations (Alvalá et al, 2019).…”