Bermuda re/insurer Arch Capital Group Ltd profits rose nearly 15 percent in the third quarter over last year despite recording almost $60 million in catastrophe losses.Arch reported net income of $162.5 million, or $1.19 per share, compared to $141.6 million, or 92 cents per share, for the 2010 third quarter.The increase in profits was all the more impressive, given the higher level of catastrophe activity. The main loss events were Hurricane Irene and floods in Denmark as Arch posted catastrophe losses of $45.5 million for events during the July through September period.An additional $14.1 million in losses resulted from increases in loss estimates relating to catastrophes that took place in the first half of the year.These losses marked a sharp increase from the $24.2 million incurred in the same period in 2010, causing the company’s combined ratio, the percentage of premium dollars spent on claims and expenses to rise 3.9 points to 94.3 percent.Arch wrote more business during the quarter with its gross premiums written rising 3.4 percent to $860.3 million from $831.8 million in 2010.Arch’s book value per common share was $31.20 at September 30, 2011, up 0.6 percent from $31 per share at June 30, and four percent higher that the $29.99 book value at the end of last year.The company’s after-tax operating income available to common shareholders represented a 10.4 percent annualised return on average common equity for the 2011 third quarter, compared to 12.3 percent for the 2010 third quarter.Arch, which is led by CEO Constantine Iordanou was one of class of 2001 companies established in Bermuda after the 9/11 attacks ten years ago.