Climatic aspects of extreme temperatures in coastal waters

Daily temperature records from Woods Hole, Massachusetts, USA are used to examine characteristics of temperature extremes from 1945 to 2006. Winter extreme temperatures are increasing at 2.0 degrees C/century compared to the rate of summer extremes of 0.8 degree C/century, which leads to a reduction of the annual temperature range. An even more intriguing result is that while summer peak is not changing, winter minimum and spring are arriving earlier by approximately 22 and 10 days/ century, respectively. The results seem to suggest that the unequal seasonal distribution of greenhouse gases could be the cause for faster winter warming trend. The mean values of the scale and shape parameters of the Weibull probability density functions for winter and summer observations are identical. The Weibull distribution parameters derived in this study can be used to estimate the hottest and coldest daily temperatures for any given year provided the mean temperature is known.