Current Glaciated Areas:

* High mountain ranges: The Alps, Himalayas, Andes, Rockies, and other high mountain ranges are home to glaciers that are actively eroding the landscape.

* Polar regions: Greenland and Antarctica have vast ice sheets that are carving out valleys, fjords, and other landforms.

* High-latitude islands: Islands like Iceland and Svalbard are also significantly shaped by glacial erosion.

Former Glaciated Areas:

* Northern Hemisphere: Much of North America, Europe, and Asia were covered by massive ice sheets during the Pleistocene ice age. These regions exhibit evidence of glacial erosion in the form of U-shaped valleys, cirques, moraines, and other landforms.

* Southern Hemisphere: Patagonia, New Zealand, and parts of South America also experienced significant glaciation in the past.

Key Factors:

* Climate: Glacial erosion is driven by cold temperatures and abundant precipitation, which allows for the formation and movement of glaciers.

* Elevation: Higher elevations are more likely to experience glaciation due to colder temperatures.

* Latitude: Higher latitudes are more prone to glaciation due to the lower solar radiation.

Specific Landforms:

* Cirques: Bowl-shaped depressions at the head of a glacier.

* U-shaped valleys: Valleys carved by glaciers, characterized by steep sides and a flat floor.

* Fjords: Deep, narrow inlets carved by glaciers and flooded by the sea.

* Moraines: Ridges of rock and sediment deposited by glaciers.

In summary, glacial erosion occurs in areas where glaciers currently exist or have existed in the past, leaving behind characteristic landforms that are evidence of their powerful erosive force.