Are today's glaciers leftovers from the Pleistocene ice age?
Yes and no. It depends on which glaciers you are considering. Parts of the Antarctic Continent have had continuous glacier cover for perhaps as long as 20 million years. Other areas, such as valley glaciers of the Antarctic Peninsula and glaciers of the Transantarctic Mountains may date from the early Pleistocene. For Greenland, ice cores and related data suggest that all of southern Greenland and most of northern Greenland were ice-free during the last interglacial period, approximately 125,000 years ago. Then, climate was as much as 3-5o Fahrenheit warmer than the interglacial period we currently live in.
Although the higher mountains of Alaska have hosted glaciers for as much as the past 4 million years, temperate glaciers in Alaska are generally much, much younger. Many formed as recently as the start of the Little Ice Age, approximately 700 years ago. Others may date from other post-Pleistocene colder climate events. Some, such as the glaciers in the summit craters of Mount Redoubt and Katmai Volcanoes, have reformed following eruptions during the 20th century.
Learn more: USGS Water Science School - Glaciers: Things to Know
Related
How does present glacier extent and sea level compare to the extent of glaciers and global sea level during the Last Glacial Maximum (LGM)? How does present glacier extent and sea level compare to the extent of glaciers and global sea level during the Last Glacial Maximum (LGM)?
The Last Glacial Maximum (LGM) occurred about 20,000 years ago, during the last phase of the Pleistocene epoch. At that time, global sea level was more than 400 feet lower than it is today, and glaciers covered approximately: 8% of Earth’s surface 25% of Earth’s land area 33% of Alaska Beginning about 15,000 years ago, continental glaciers retreated and sea level began to rise. Sea level reached...
How would sea level change if all glaciers melted? How would sea level change if all glaciers melted?
There is still some uncertainty about the full volume of glaciers and ice caps on Earth, but if all of them were to melt, global sea level would rise approximately 70 meters (approximately 230 feet), flooding every coastal city on the planet. Learn more: USGS Water Science School: Glaciers and Icecaps National Snow and Ice Data Center: Facts about Glaciers U.S. Global Change Research Program: Sea...
Is there a size criterion for a glacier? Is there a size criterion for a glacier?
While there is no global standard for what size a body of ice must be to be considered a glacier, USGS scientists in Glacier National Park use the commonly accepted guideline of 0.1 square kilometers (about 25 acres) as the minimum size of a glacier. Below this size, ice is generally stagnant and does not have enough mass to move. Learn more: Status of Glaciers in Glacier National Park
What is a glacier? What is a glacier?
A glacier is a large, perennial accumulation of crystalline ice, snow, rock, sediment, and often liquid water that originates on land and moves down slope under the influence of its own weight and gravity. Typically, glaciers exist and may even form in areas where: mean annual temperatures are close to the freezing point winter precipitation produces significant accumulations of snow temperatures...
Related
How does present glacier extent and sea level compare to the extent of glaciers and global sea level during the Last Glacial Maximum (LGM)? How does present glacier extent and sea level compare to the extent of glaciers and global sea level during the Last Glacial Maximum (LGM)?
The Last Glacial Maximum (LGM) occurred about 20,000 years ago, during the last phase of the Pleistocene epoch. At that time, global sea level was more than 400 feet lower than it is today, and glaciers covered approximately: 8% of Earth’s surface 25% of Earth’s land area 33% of Alaska Beginning about 15,000 years ago, continental glaciers retreated and sea level began to rise. Sea level reached...
How would sea level change if all glaciers melted? How would sea level change if all glaciers melted?
There is still some uncertainty about the full volume of glaciers and ice caps on Earth, but if all of them were to melt, global sea level would rise approximately 70 meters (approximately 230 feet), flooding every coastal city on the planet. Learn more: USGS Water Science School: Glaciers and Icecaps National Snow and Ice Data Center: Facts about Glaciers U.S. Global Change Research Program: Sea...
Is there a size criterion for a glacier? Is there a size criterion for a glacier?
While there is no global standard for what size a body of ice must be to be considered a glacier, USGS scientists in Glacier National Park use the commonly accepted guideline of 0.1 square kilometers (about 25 acres) as the minimum size of a glacier. Below this size, ice is generally stagnant and does not have enough mass to move. Learn more: Status of Glaciers in Glacier National Park
What is a glacier? What is a glacier?
A glacier is a large, perennial accumulation of crystalline ice, snow, rock, sediment, and often liquid water that originates on land and moves down slope under the influence of its own weight and gravity. Typically, glaciers exist and may even form in areas where: mean annual temperatures are close to the freezing point winter precipitation produces significant accumulations of snow temperatures...