3. Overview of Suicide Cases in East Java Province for the 2015-2019 Period
Suicide always occurs throughout the year in East Java Province. These suicides can be seen in the results of studies that show that suicide cases always fluctuate from month to month or from year to year.
Based on the results of observations made over the last 4 years, when viewed from the number of cases per month, the highest average suicide cases were in February and March, namely 3 cases and the lowest average suicide cases were in May and June, with a total of 1.25. case.
4. The Relationship between Air Temperature and Suicide Cases in East Java Province for the 2015-2018 Period
The results of the correlation test of air temperature and the incidence of suicide in East Java Province in 2015-2018, when viewed per month, show a weak correlation (r = -0.139) and a negative pattern meaning that the higher the temperature, the lower the suicide rate or vice versa. Based on the significant level between air temperature and the incidence of suicide, there is no significant correlation (p = 0.667).
The relationship between air temperature and the incidence of suicide in East Java Province in 2015-2018, when viewed from the annual data, shows a moderate correlation (r = -0.48) and has a negative pattern, meaning that the higher the air temperature, the higher the suicide rate or on the contrary. Based on the significance level, it shows no statistically significant correlation between air temperature and the incidence of suicide (p = 0.52).
This study is not in line with research conducted by Gao et al. (2019), which states that there is a relationship between air temperature and suicide cases (p <0.05), and Kayipmaz et al. (2020) concluded that there is a relationship between air temperature and suicide cases. (p = 0.046) in Turkish cities in 2017 – 2019. However, this aligns with research conducted by Makris et al. (2021), which showed no relationship between suicides and air temperature.
5. Relationship between Rainfall and Suicide Cases in East Java Province for the 2015-2018 Period
The highest incidence of suicides in East Java Province was in February. This suicide was followed by a high rainfall intensity of 453.2 mm. The relationship between rainfall and the incidence of suicide in East Java Province in 2015–2018, when viewed per month, shows a very strong correlation (r = 0.8455) and has a positive pattern meaning that the higher the rainfall, the higher the suicide rate. Based on the significant level between rainfall and the incidence of suicide, there is a significant correlation (p = 0.000).
The simple linear regression analysis results predict that the rainfall variable is significantly related to the number of suicide cases (p = 0.000) with a coefficient of 0.02. This means that the number of suicides is predicted to increase by 0.02 if the rainfall value increases by one unit (millimeter) with a positive effect. In other words, if the rainfall value increases by 1mm, it will result in a change in the number of suicides increasing by 0.02 or vice versa. The rainfall variable influences suicide cases by 71.5% (R2 = 0.715).
The relationship between rainfall and the incidence of suicide in East Java Province in 2015 - 2018, when viewed from the annual data, shows a moderate correlation (r = -0.41) and has a negative pattern, meaning that the higher the rainfall, the lower the suicide rate. Based on the significance level, it shows no statistically significant correlation between rainfall and the incidence of suicide (p = 0.59).
The results of this study are in line with the research of Nicholls et al. (2006), which stated that there was a relationship between rainfall and suicide cases in Australia in 1964-2001 and were not in line with Nino et al. (2018) which stated that there was no relationship between suicide cases and rainfall.
6. Air Humidity Relationship with Suicide Cases in East Java Province in the 2015-2018 Period
Air humidity with the incidence of suicide in East Java Province in 2015 - 2018 shows a strong correlation (r = 0.634) with a positive pattern, meaning that the higher the humidity, the higher the suicide rate. Based on the significance level, it shows a statistically significant correlation between air humidity and the incidence of suicide (p = 0.028).
The simple linear regression analysis results predict that the air humidity variable is significantly related to the number of suicides (p = 0.028) with a coefficient of 0.33. This means that the number of suicides is predicted to increase by 0.33 if the air humidity value increases by one unit (percent) with a positive effect. In other words, if the air humidity value increases by 1%, the number of suicide cases increases by 0.33 or vice versa. The air humidity variable influences suicides by 40% (R2 = 0.4).
The relationship between air humidity and the incidence of suicide in East Java Province in 2015-2018, when viewed from the annual data, shows a strong correlation (r = -0.735) and has a negative pattern, meaning that the higher the humidity, the lower the suicide rate or vice versa. Based on the level of significance, it shows that there is no statistically significant correlation between air humidity and the incidence of suicide (p=0.286). These results were not in line with Ngu (2021), which states that relative humidity showed a more significant correlation with suicide and women seemed to be more significantly affected by changes in humidity.
Low rainfall indicates that the area has low air humidity, so the area has a dry climate. Or conversely, high rainfall indicates that the area has high air humidity, so the area has a wet climate. This affects the agricultural sector. At too high a humidity, fungi and bacteria can grow and cause damage or decay to plants. In addition, high air humidity can lead to a higher risk of respiratory infections. Low humidity can cause respiratory irritation due to a lack of mucus to catch dust, viruses, and microorganisms, so the effects of high humidity can be the same as high rainfall, namely on the economy, health, and other aspects.
7. The Relationship between Wind Speed and Suicide Cases in East Java Province for the 2015-2018 Period
The relationship between wind speed and the incidence of suicide in East Java Province in 2015-2018, when viewed per month, shows a weak correlation (r = -0.007) and has a positive pattern, meaning that the higher the wind speed, the higher the suicide rate. Based on the significant level between wind speed and the incidence of suicide, there is no significant correlation (p = 0.68).
The relationship between wind speed and the incidence of suicide in East Java Province in 2015-2018, when viewed from the annual data, shows a weak correlation (r = -0.057) and has a negative pattern meaning that the higher the wind speed, the lower the suicide rate or vice versa. Based on the significance level, it shows no statistically significant correlation between wind speed and suicide (p = 0.943).
This result is in line with Fernández's research which states that women's suicides with higher wind speed in comparison to men (P=.043) in the province of Córdoba.