Xinhua: Shanghai has experienced the hottest year in 2007 since the city began to record weather in 1873, with an average temperature of 18.4 Celsius degrees, said meteorologist on Saturday. The year’s average in 2007 is 2.2 Celsius degrees more than the long-term average temperature of 16.2 degrees, and is even 0.1 Celsius degree more than that of last year, said Shen Yu, senior engineer with the municipal meteorological bureau. "Especially in February, May and July, the …