81011515

open access

Version of Record

EVALUATION OF TRENDS AND VARIABILITY IN SEA LEVEL, TEMPERATURE AND PRECIPITATION OF JAPAN: LINKS TO CLIMATE VARIABILITY AND CHANGE

神戸大学都市安全研究センター研究報告

20

140-149

神戸大学都市安全研究センター

2016-03

2019-05-30

Trends and changes in sea level, temperature and precipitation data at a number of observation sites located uniformly across Japan are evaluated in this study. Influence of climate variability based two coupled oceanic and atmospheric oscillations (viz., ENSO: El Niño Southern Oscillation, PDO: Pacific Decadal Oscillation) on these hydroclimatic variables is evaluated. A total of 14 observation sites for sea level rise analysis, 156 and 155 observation sites for evaluations of temperature and precipitation variables respectively are used in this study. Parametric and nonparametric statistical inference and trend tests are used in the current study. Spatial interpolation along with geo-spatial analysis and smoothing methods (e.g. kernel density smoothing) were used for analysis. Historical monthly data used for analysis points to: (1) statistically significant increasing trends at majority of the sea level observation sites; (2) spatial and temporal non-uniform decreasing and increasing trends for precipitation and temperature; (3) increasing and decreasing trends are noted in several extreme indices and (4) decreasing precipitation and increasing temperature in the second temporal window (i.e. 1981 -2015) compared to first one (i.e. 1950 -1980). The study provides insights into influences of two oscillations namely ENSO and PDO on three variables in the region. Further studies can be conducted using the methods of analysis reported in this study to evaluate changes in the variables at finer temporal scales other than month. Influences of climate variability and climate change on these three variables have wide range of implications for agricultural production, coastal flooding and storm water management due to extreme events and water stress due to changing temporal availability of water in many regions of Japan in the near and distant future.

standard precipitation index (SPI).

紀要論文