Indices of trends of climatic changes for the states of the Bahia and Sergipe by means of daily precipitacion indices and its relation with SST'S of the Pacific and Atlantic

Abstract

The objective of this study was to investigate statistically the precipitation variability in annual scale from the states of the Bahia and Sergipe using daily precipitation data. From that, indexes of detection of climate changes were calculated to evaluate the relationship of the most significant indexes with the sea surface temperature (SST) anomalies of the Pacific and Atlantic oceans. The daily precipitation data used were for a period of 45 years of 75 meteorological stations supplied by the old net of the SUDENE available in the DSA and data of the of the SST anomalies obtained from NOAA. Influence of SST of the Pacific and Atlantic oceans on the precipitation of the studied area is evidenced. A decrease of CWD was verified; increase was observed in the number days with rain; therefore, the amount of annual total precipitation increased. Several stations presented positive or negative tendencies in all examined indexes, consequently, they are also related to regional aspects. Therefore, it is not possible to affirm that the climate alterations noted in the study area are due to the global climate changes.

Risk identification of precipitation extremes due to climate change in the southern region of the state of Rio de Janeiro

“…The monthly maximum rainfall in 5 consecutive days showed results opposite to the previous index, presenting negative linear trend, but positive trend MK tent z = 1.37, non-significant (Figure 9). The same results were found by Araújo & Brito (2011), who observed positive trend for the Rx1day index and negative trend for the Rx5day index. However, Assis et al (2012) found decreasing trends for the Rx1day and Rx5day indexes.…”

“…In addition to rainfall, negative events are also characterized by local geology, mainly due to soil properties (Silva et al, 2016). Araújo and Brito (2011) found positive trend for R95p and negative trend for R99p. The research carried out by Souza and Azevedo (2012) identified reduction in wet and extremely wet days.…”

“…These results can be verified by the 99th percentile index (R99p), with MK test z = 1.21 (Figure 7). According to Araújo and Brito (2011), R95p and R99p indexes are related to precipitation extremes that characterize the amount of rain concentrated in rainy events, indicating rainfall associated with flooding in rivers and reservoirs. The thermodynamics and dynamics have comparable contributions to the intensified precipitation extremes.…”

“…Some of these events causes harm to society, such as significant economic losses, which can cause contamination, threat to public health and even death. For the Northeastern region of Brazil, studies such as those by Araújo and Brito (2011); Assis et al, (2012); Souza and Azevedo (2012) and Wanderley et al (2014) have shown changes in rainfall distribution, some of these changes with statistical significance.…”

Trends in Temperature and Rainfall Extremes near the Artificial Sobradinho Lake, Brazil

“…Consistent with the above results, an increase in hot days and maximum temperature agrees with an increase in consecutive dry days as the SST in the Pacific Ocean increases. Araújo and Brito (2011) investigated the influence of SST in the Pacific and Atlantic Oceans in the precipitation of the states of Bahia and Sergipe using extreme climatic indices. Their results showed positive correlations between the CDD indice and the North Atlantic region, differently from our study, which found positive correlations between the CDD indice and the Niño regions.…”