Normally, it would take hundreds to thousands of years for it all to melt away. But what if something happened that caused a massive global melt overnight? As we slept, sea levels would rise by a whopping 66 meters. While all this chaos ensues aboveground, something equally sinister is happening below. All that rising saltwater will infiltrate groundwater reserves farther inland, forcing its way into nearby freshwater aquifers.
You know, the ones that supply our drinking water, irrigation systems, and power-plant cooling systems? All those aquifers would be destroyed. Not good. This will wreak havoc on our ocean currents and weather patterns. Take the Gulf Stream, for example. It's a strong ocean current that brings warm air to northern Europe and relies on dense, salty water from the Arctic in order to function.
But a flood of freshwater would dilute the current and could weaken or even stop it altogether. Without that warm air, temperatures in northern Europe would plummet, and that could spawn a mini ice age, according to some experts. That's not even the worst of it. The Himalayan glaciers specifically pose one of the largest threats because of what's trapped inside: toxic chemicals like dichlorodiphenyltrichloroethane, or DDT.
Scientists discovered that glaciers like this can store these chemicals for decades. Well, fine as an estimation—not fine as the disaster it would cause. But what about the melting ice at the North Pole? Although there is significant melting , it doesn't contribute to sea level rise.
The big difference is that the Arctic ice is floating while the Antarctic ice is sitting on land. Why does this even matter? I can show you with an example of a classic physics question. Imagine you have a glass of water with a single large ice cube in it.
Since the density of solid ice is slightly less than the density of liquid water, the ice floats. Here is a diagram of the floating ice. Why does stuff float? I know this might seem crazy, but it's because of the gravitational force.
Imagine that you have a glass of water without any motion in the cup no currents. You can take a small section of the water in the middle of the cup and look at the forces acting on it. Let's say this is a small cube of water with each side of length s. Since the water block is stationary, the total force on this block must be zero—this is true for any object in static equilibrium.
One force that should obviously be acting on the water block is the downward pulling gravitational force. But then what force pushes UP on the water?
The answer is more water. Yes, the water below this block pushes up on the water above it the original block of water. This is the only way for the water to stay stationary—so, it has to be true. We call this upward pushing force from the water the buoyancy force. The buoyancy force on the small block of water has to be equal to the gravitational force pulling down on the water.
Now, what if I replace this water block with a metal block of the exact same size? Well, there's still water outside the metal block. It should still push on it in the same way it interacted when there was a block of water.
That means you still get the same upward buoyancy force that would be equal to the weight of the water block not the metal block. In the case of this metal block, that buoyancy force would not be enough to keep it floating and it would sink—but that buoyancy force would still be there. So what does this have to do with the Arctic ice?
If you have ice floating in the water, it displaces some liquid water. But since it's floating, it will displace a volume of water that would have an equal mass as the ice. Now, imagine the ice melts. Even though the volume of material changes as the ice goes from a solid to a liquid, the mass stays the same. Now the melted ice so, the new water occupies the same volume of water that the ice cube displaced. Nothing changes.
Go back to the melting ice in a glass of water. The total water level in the glass will stay the same as a block of ice melts assuming there wasn't any evaporation. About three-quarters of Earth's freshwater is stored in glaciers Invalid Scald ID.
What are the impacts of glacier loss, other than losing an aesthetic landscape feature? Glaciers act as reservoirs of water that persist through summer. Continual melt from glaciers contributes water to the ecosystem throughout dry months, creating perennial stream habitat and a water source for plants and animals. The cold runoff from glaciers also affects downstream water temperatures. Many aquatic species in mountainous 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 do we know glaciers are shrinking? The USGS Benchmark Glacier project has collected mass balance data on a network of glaciers in Alaska, Washington, and Montana for decades, quantifying trends of mass loss at all sites. Extensive field data collection at these 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. Below this size, ice is generally stagnant and does not have enough mass to move. Learn more Filter Total Items: Year Published: Glacier retreat in Glacier National Park, Montana Currently, the volume of land ice on Earth is decreasing, driving consequential changes to global sea level and local stream habitat.
View Citation. Florentine, C. Geological Survey Fact Sheet —, 2 p. Year Published: U. Burkett, Virginia R. Burkett, V. Geological Survey climate and land use change science strategy—A framework for understanding and responding to global change: U.
Geological Survey Circular —A, 43 p. Year Published: Land subsidence and relative sea-level rise in the southern Chesapeake Bay region The southern Chesapeake Bay region is experiencing land subsidence and rising water levels due to global sea-level rise; land subsidence and rising water levels combine to cause relative sea-level rise. Year Published: Assessing hazards along our Nation's coasts Coastal areas are essential to the economic, cultural, and environmental health of the Nation, yet by nature coastal areas are constantly changing due to a variety of events and processes.
Hapke, Cheryl J. Attribution: St. Virgin Islands. Williams, Richard S. Year Published: The United States National Climate Assessment - Alaska Technical Regional Report The Alaskan landscape is changing, both in terms of effects of human activities as a consequence of increased population, social and economic development and their effects on the local and broad landscape; and those effects that accompany naturally occurring hazards such as volcanic eruptions, earthquakes, and tsunamis.
Markon, Carl J. Stuart; Markon, Carl J. Stuart, III. Year Published: USGS science for the Nation's changing coasts; shoreline change assessment The coastline of the United States features some of the most popular tourist and recreational destinations in the world and is the site of intense residential, commercial, and industrial development.
Thieler, E. Robert; Hapke, Cheryl J. Barnhardt, Walter A. Geological Survey. Year Published: A strategy for monitoring glaciers Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Fountain, Andrew G. Year Published: Sea level change: lessons from the geologic record Rising sea level is potentially one of the most serious impacts of climatic change. Sea level change: lessons from the geologic record; ; FS; ; U.
Year Published: Glaciers: A water resource Most Americans have never seen a glacier, and most would say that glaciers are rare features found only in inaccessible, isolated wilderness mountains. Filter Total Items: 9. Date published: March 13, Date published: May 10, Date published: October 3, Date published: September 23, Date published: August 14, Date published: March 18, Date published: December 9, Attribution: Chesapeake Bay Activities.
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