Current Status of Time Series Analysis in Hydrological Sciences - Hydrologic Time Series Analysis: Theory and Practice - page 114

region, the aquifer's groundwater resources seem to be threatened under 2xCO 2
climate scenarios. It was also found that the 2xCO 2 climatic conditions could
exacerbate negative impacts and water shortages in the Edwards BFZ aquifer
even if pumping does not increase above its present average level. Based on
the historical evidence and the results of this study, it was concluded that
without proper consideration to variations in aquifer recharge and sound
pumping strategies, the water resources of the Edwards BFZ aquifer could be
severely affected under a warmer climate.
Burn and Elnur (2002) analyzed 18 hydrologic variables for a network of
248 Canadian catchments reflecting natural conditions. The Mann-Kendall
test was used to detect trends and a permutation approach was used to estimate
the test distribution. The catchments having trends in hydrologic variables
were further studied to examine trends in meteorological variables and explore
the relationship between hydrologic and meteorological responses to climatic
change. It is concluded that a greater number of trends were detected than are
expected to occur by chance. There were differences in the geographic location
of significant trends in the hydrologic variables, which indicated that the
climatic impacts were not spatially uniform.
Yu et al. (2002) investigated the impact of climate change on the water
resources of the Kao-Pen Creek basin in southern Taiwan. The historical
trends of salient meteorological variables (i.e., mean daily temperature, mean
daily precipitation on wet days, monthly wet days, and the transition
probabilities of daily precipitation occurrence in each month) were detected
using the nonparametric Mann-Kendall test. The trends of these meteorological
variables were then employed to generate runoff under future climatic
conditions using a continuous rainfall-runoff model. The results indicated that
the transition probabilities of daily precipitation occurrence significantly
influence the precipitation generation, and the generated runoff under future
climatic conditions was found to increase during the wet season and decrease
during the dry season.
6.3 Application of Time Series Analysis in Surface
Water Hydrology
6.3.1 Streamflow
Cehak (1979) performed the frequency analysis of the flood data from five
stations in the east Alps rivers by using Fisher-Tippett II and III distributions.
The data of the longest observation periods were fitted well to the Type II
distribution. A comparison of the calculations with only a part of the
observations showed that the magnitude of the curvature parameter k of the
Fisher-Tippett curves increases with increasing observation periods. A trend
test indicated an increasing trend in all of the Danube stations after about 1860
and no trend in the flood data from southern rivers. The variance spectra