Mean Temperature Projection by PRECIS over Pakistan for 2001-2010

The regional climate model PRECIS (Providing Regional Climate for Impact Studies) of the Headley Centre, Met Office UK, was used to simulate temperature along with other parameters at 0.22 ° × 0.22 ° (about 25 km × 25 km) resolution for Pakistan. The PRECIS output mean temperature was compared with two datasets; (1) a published dataset of CRU (Climate Research Unit) developed by the University of East Anglia, which is a dataset prepared from the real time data of station observatories all over the world, and (2) real time temperature data of the observatories of Pakistan Meteorological Department (PMD). While there is a large scale agreement between these datasets, considerable regional differences also exist. During the summer season (JJA, i.e. June, July and August) the PRECIS is warm bias in Punjab, southern Khyber Pakhtoonkhwa, northern Sindh and the adjoining areas, while this trend shrinks to a smaller region during the winter season of DJF (i.e. December, January and February) as compare to the observed temperature data sets (i.e. both CRU and PMD observed temperature data). Overall the PRECIS predicted temperature is in good agreement with CRU and PMD observed temperature in the lower plane areas of the country with slight differences, whereas in the northern hilly areas of complex topography there exist large biases between these datasets (i.e. PRECIS and the two observed datasets). Thus the model behavior is rather a chaotic one in the regions with latitude greater than 30 ° (more precisely in the regions with latitudes greater than 33 ° ). The correlation between PRECIS and PMD observed temperature in the regions with latitude smaller than 30 ° is better than the correlation between them in the region with latitude greater than 30 °