Trend Analysis of Temperature over New South Wales

摘要

The study has primary objective is to study trends in monthly mean maximum temperature in New South Wales (NSW) over 46 years periods from 1966 to 2011, for this purpose, non-parametric rank based Mann Kendall’s tau test were employed. The study explore that increasing trends all over the state dominates over negative trends, all 288 stations are analyzed out of which all stations shows trends (positive and negative trends), 51.04 percent of stations shows significant positive trends at 99% level of significance, while only 7 percent of the stations shows decreasing trends (not significant). Maximum number of significant increasing trends are recorded in the month of September (24), while maximum number of decreasing trends are in month of August (8), though they are not significant, these declining trends are observed mostly in northern part of NSW over Western slopes, Tablelands and coastal strip climate zone. Minimum number of significantly increasing trends where observed in months of February, May, July and December, i.e. only two stations, whereas no station showed significant decreasing trends at any level of significance. Seasonal variability is also evident from the study, for instance, December, January and February, have least number of significant trends, while maximum number of trends were observed in early winter season i.e. May, June and July. The study does not aim to explore possible factors affecting temperature trends in NSW.