And where does it claim that glaciers worldwide are currently melting rapidly?

Here something that might be helpful:

"The temperature at which a glacier melts is a function of the pressure and the overlying weight of the glacier. A glacier may be classified as cold (polar) or warm (temperate). A cold glacier has a temperature below the melting point of ice from top to bottom. Such glaciers get warmer with depth. A warm glacier is at the pressure-melting temperature throughout. Glacier ice at the melting point is in equilibrium with liquid water, so water can exist throughout warm glaciers all the way to the base.

Most glaciers move slowly, a few centimeters to less than a meter a day. However, some glaciers move very rapidly. For example, surge-type and tidewater glaciers can move very rapidly for short periods of time. A surge-type glacier experiences a relatively short-lived episode of greatly-accelerated flow followed by a relatively longer period of stagnation and retreat. Velocities of surge-type glaciers as high as 105 m per day have been recorded (Paterson, 1994). Tidewater glaciers go through a cycle (Meier and Post, 1987): the glacier will occupy a stable position with the terminus at the head of a fjord, experience a slow advance that may last 1000 years, remain relatively stable and then experience a rapid retreat that may last less than a century. This cycle is not directly related to short-term climate change. An excellent example of tidewater glacier retreat is the Muir Glacier in Glacier Bay, Alaska. "
http://modis-snow-ice.gsfc.nasa.gov/glacier.html