## 3 Results
### Temporal Analysis and Trend Analysis  
The temporal analysis of droughts sheds light on the long-term drought conditions of that region and, therefore, are a significant part of drought study. Figures 10-14 display the 3-month SPEI of each region from 1902-2015 along with the least squares regression line. The wet and dry periods can be clearly visualized. Substantial differences in the drought characteristics in each zone were observed. Figures 15-18 show the drought duration, severity, intensity, and peak for each zone from 1902-2015. Figure 14: Three-month SPEI from 1902–2015 for zone 5. Figure 12: Three-month SPEI from 1902–2015 for zone 3. Figure 13: Three-month SPEI from 1902–2015 for zone 4. Figure 16: Drought severities for each zone. Figure 15: Drought durations for each zone. In zone 1, three events are of particular interest. The first is the period from 1946-1953, where, in addition to experiencing multiple droughs, the SPEI in the area never exceeded the 0.75 mark. Three severe droughs also occurred in this period. A similar dry pattern is seen from 1984-1989 in which the positive SPEI remained considerably less than 1. Finally, the four-year period from 1998-2002 also displays an extended period of dryness. For zone 2, the drought behavior can be divided into two distinct periods. Droughs before 1960 occurred  
Throughout the study period, drought peak in zone 5 never fell below -1.6 as can be seen in Figure 18. However, looking at Figure 15, we can see that droughts with longer duration and greater severity have occurred in zone 5 as compared to other zones. After a long-term drought in the early 1920s, the area experienced dry spells again at the end of 1967, 1987, and 1999. Table 1 summarizes the results of the Mann-Kendall trend test applied to SPEI, drought duration, severity, intensity, and peak of each zone. The SPEI in each zone except zone 1 demonstrates a statistically significant trend after applying the modified Mann-Kendall trend test. Zones 2 and 3 are getting wetter over time, whereas zones 4 and 5 display a drying trend as signified by their respective Sen's slope value. The trend analysis did not capture any trend in drought duration in any zone. Drought severity in zones 1 and 4 is getting worse, but it is lessening in zone 2. Zones 3 and 5 show no statistically significant trend for drought severity. Moreover, the positive value of Sen's slope for drought intensity in zone 2 indicates an increasing value of intensity over time, which means drought is getting less intense. In contrast, zone 4 has a negative Sen's slope, which means that droughts are getting less intense with time. No statistically significant trend was observed in zones 1, 3, and 5. Furthermore, drought peaks show an increasing trend in zone 2 and, therefore, peaks are getting smaller (less negative) over time. Peaks in zones 4 and 5 show a negative trend indicating that peaks are getting worse over time, whereas no significant trend was detected for zones 1, 2, and 3. Characteristics of droughts in each zone of duration more than 10 months are tabulated in Table 2. Zone 1 had two instances of droughts having a duration of more than 10 months. The first started in late 1999 and ended in mid-2001. It lasted 19 months with a mean intensity of \(-1.10\). The other