Remote Sensing Detection of Droughts and Efficient Water Resource Allocation in Korea

One of the most significant impacts of climate change might be related to hydrological cycles. These days, many countries are experiencing the rapid shifts in water balance without enough preparation. These accelerated and unpredictable changes directly affect human and society in various fields such as agriculture (food system), ecosystem, human health, and water supply. According to IPCC(1998), water stress in Asia are expected to be exacerbated by climate change. More serious measures are highly required.

The drought cannot be defined simply. Most people think of drought as a long dry and hot period with a lack of precipitation. However, drought should not be seen as a simple physical phenomenon. Drought is the result of a complicated interplay between natural precipitations and the demand placed on water supply (Wilhite and Vanyarkho, 2000). Therefore, the extent and severity of drought would be reduced with several measures.

The Korean peninsula suffered severe drought this year. The prices for a variety of agricultural commodities soared and many people had a difficult time due to water shortage. According to Kim et al (2011), spring droughts tend to be short and summer droughts tend to be long. Based on this trend, more sophisticated actions should be followed to prevent severe drought.

Drought is commonly measured by Palmer drought index (PDI). PDI was devised to measure the duration and intensity of the long-term drought, which provides a simple and useful method for deciding severity of drought. However, there are two drawbacks for this index. This index does not consider hydrological variables such as reservoir levels and ground water. Moreover, temperature and precipitation data provide only point data, not providing plane or 2-dimensioanl data. In this sense, alternative method can provide a different prospective. One alternative method would be a remote sensing. This method could provide a powerful tool for assessing large and remote areas. Several papers have already tried to use satellite images to detect drought (Kuenzer et al., 2008, Anderson et al., 2010, Marrufo et al. 2011). The objectives of this research are followings. 1. Comparison of the amount of soil moisture regarding each region 2. Time series of soil moisture

Based on the above results, measures for efficient allocation of water resources will be discussed and economic, social, health, environmental impacts of drought also will be briefly discussed.