Is there Global warming?   Time Series Analysis of Global Temperature anomolies.

Tata Subba Rao, UMIST

One of the hottest(!) topics of the present day (besides terrorism) is Global warming.   A number of scientific articles have been written and every day we come across an article by science corespondents with scientific evidence showing that there is significant global warming.   We refer to the recent article by Mark Henderson (The Times,Friday March 5,2004) entitled: Past ten summers were the hottest in 500 years.   In our present paper we consider time series analysis of the monthly Global Temperature anomalies (observed over the past 150 years) and show through nonstationary models that there is significant increase.   Using CUSUM charts and nonstationary spectral methods, we try to detect change points.   We believe the change points correspond to significant historical changes in the climate.   Our analysis is only a starting point in this new direction.