Drought Assessment Using Standardized Precipitation Index (SPI) Case Study: Sulphur Springs Tampa FL

Climate change and extreme events with Uncontrolled Urbanization cause environmental degradation and long-term impacts on human life. The water as the most precious commodity on the global has been affected as a result from this environmental degradation. The availability of fresh water in term of quality and quantity is an essential matter to be monitored and controlled to avoid subsequences that could be threaten for human life. Drought is emerging as a sign of water resource deterioration which required to be monitored and diagnosed. Drought events can be diagnosed from changing in precipitation, temperature, groundwater, and water resources. The drought indices are very important as an effective early warning system to help the decision makers for an appropriate measure to reduce the impacts of drought. In this study we are trying to assess the regional drought and its effect on the Sulphur Springs Nitrate concentration and the causes of Sulphur Springs streamflow depletion. Standardized Precipitation Index SPI Standardized Discharge Index (SDI) are used to estimate the dry and wet conditions. These conditions can by estimated on time scales verity based on precipitation records and data. The calculation of SPI index is based on rainfall distribution and long-term period for a specific location. The precipitation records should be normally distributed for fitting in the Standardized Precipitation Index SPI. A location has been selected to apply the method, then to be validated for other arid and semi-arid locations. The availability of data and weather conditions play a significant role for this selection. Monthly precipitation records during the period Jan-1988 to 2014 over Sulphur Springs County in Tampa, Florid, has been obtained to apply the Standardized Precipitation Index (SPI). These data will be used to compute and verify the SPI and SDI results. SPI is calculated at one location in Tampa, Florida to monitor the drought phenomena in regional scale. The basic data which is used in this analysis is cumulative monthly precipitation to calculate the SPI for 3, 6, and 12 Monthly events and 3, 9, and 12 for the SDI computation. The SPI and SDI responds effectively to analyze drought conditions and monitor drought events. The precipitation has a stable trend along the period of study while the Spring tend to have a decreasing pattern. The index shows that the spring in Tampa has suffered from drought between 2000 to 2004. These impacted water quality and human life in terms of quantity by clogging the springs and quality by increasing the pollutant concentration during the drought.