Glaciers and Human Impacts

Question

Glaciers are slow-moving masses of snow and ice that erode Earth’s surface as they move. Their enormous mass also presses into Earth’s surface, carving out land features.

Glaciers are important sources of water for bodies of water, including rivers, lakes, and oceans. As glaciers melt, they release water that flows down mountain slopes and into bodies of water. Water that comes from glaciers helps control the volume and flow rate of water in rivers, the salinity (salt content) of water in oceans, and the temperature of water in rivers, lakes, and streams.

Data show that many of Earth’s glaciers are losing mass (decreasing in size). Scientists claim that increasing average temperatures in arctic regions are causing this loss of glacial ice.

Constructed Response Question
A. Describe the MOST LIKELY effect of increased rates of glacial melting on the volume of water in the world’s oceans and on overall sea level.

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Constructed Response Question
B. Describe the MOST LIKELY effect of sea level change described in Part A on the rate of coastline erosion. Explain why this sea level change would have this effect.

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Answer 1

A. Describe the MOST LIKELY effect of increased rates of glacial melting on the volume of water in the world’s oceans and on overall sea level.

Increased rates of glacial melting are likely to lead to a significant rise in the volume of water in the world’s oceans, consequently causing an increase in overall sea levels. As glaciers melt, the freshwater released flows into the sea, contributing directly to ocean water volume. This process is particularly pronounced in regions with large ice sheets, such as Greenland and Antarctica, where substantial quantities of ice are being lost. The result of this melting is a gradual elevation of sea levels, which poses risks to coastal communities, ecosystems, and infrastructure around the world, leading to potential flooding and increased salinity in coastal aquifers.

B. Describe the MOST LIKELY effect of sea level change described in Part A on the rate of coastline erosion. Explain why this sea level change would have this effect.

The increase in sea level due to rising ocean volumes from glacial melting is likely to accelerate the rate of coastline erosion. Higher sea levels mean that ocean waters encroach further inland, inundating shorelines and increasing the force of waves against the coast. This can lead to the loss of coastal land that was previously protected from wave action. Additionally, as the sea level rises, the energy and power of waves on the shoreline can intensify, leading to greater erosion of sand and soil. The increased frequency and intensity of storm surges during weather events can also result in more significant coastal damage, exacerbating the erosion process. Ultimately, as coastlines are further exposed to rising waters and enhanced wave action, erosion rates will increase, threatening habitats, human settlements, and natural landscapes.