Whilst every glacier in the world is not melting and retreating (nor would they be expected too - climate change means some will grow as some areas get colder and have greater precipitation of snow and ice) it is true that the vast majority are shrinking due to gradually rising temperatures. Around 95% of the glaciers outside Antarctica are retreating. This is a very slow occurrence, however. Indeed, "glacial slowness" is a well-known metaphor for a very slow process. Enter the time lapse camera, which is the best way of showing the changes in an obvious way.
Here are two videos about the glacial retreat. The second one is probably the most dramatic but, as it is one of the excellent TED talks, there is about 10 minutes preamble (which is very well worth listening to) before the time lapse movie is shown. The whole clip is about 20 minutes in total. Bear in mind with time lapse films of glaciers that you will see the seasonal variations too – glaciers advance in winter and retreat during summer – like waves of ice breaking upon a shore. The long term time lapse shows that the “tide” of ice is indisputably going out as the climate is changing.
Photographer James Balog shares new image sequences from the Extreme Ice Survey, a network of time-lapse cameras recording glaciers receding at an alarming rate, some of the most vivid evidence yet of climate change.