The following images are frames from simulations of glaciers evolving in the Indian Peaks. Meshed areas represent glaciers; smoothly colored areas represent bare bedrock. The thick blue lines indicate the equilibrium line altitude imposed in that simulation. In the movies, the lower frame shows the ELA time series; the open circle tracks along in sync with the upper frame. [click image to download movie]
View is Northwest toward the Arapaho Peaks. The snouts of Middle and North Boulder Creek glaciers extend furthest toward the spectator. North Boulder glacier (rightmost of the two) is in position to dam Caribou Creek and create Glacial Lake Devlin. In the simulation, an ELA of 3500 m was imposed for the first 500 years, then the ELA was lowered to 3350 m. About 300 years after the change in climate, the glaciers come to a steady state just outside of Nederland. This final configuration is meant to represent last glacial maximum conditions (~14 ka). 
View is toward the Northwest, up the north fork of Middle Boulder Creek, with South Arapaho Peak in the far right corner. Initially, a glacier near steady state with a climate characterized by an ELA of 3500 m exists. After 100 years, the ELA starts rising by 2 m/year, continuing for 100 years. Then the ELA lowers at a rate of 2 m/year down to the initial value of 3500 m. A lag in the glacier's recovery is evident, and it isn't until about 200 years after the ELA of 3500 is reinstated that the glacier reaches its former size.
Links:
High Surfaces (an ongoing project of R.S.A and M.A.K)
Miscellaneous glacier simulations:
Baffin Island Fjords