The Ross Ice Shelf is the largest ice shelf in Antarctica, with an area about the size of France! It is named after its discoverer Captain Sir James Clark Ross, not Ross Geller. So what exactly is an ice shelf? Well, ice shelves are formed when glaciers or ice sheets flow down to the ocean surface. These flat masses of ice connected to land are found exclusively in Antarctica, Greenland, Canada, and Russia. Ice shelves are like brake pedals, limiting the amount of melting that occurs on glacial surfaces. When ice shelves are calved or collapsed, glaciers get excited and start dumping more snow than accumulating it. By doing so, they retreat and cause sea levels to rise, which contributes to climate change. But what makes the Ross Ice Shelf so interesting?
Well, the extensive shelf has a width of approximately 800 km and a length of 970 km, meaning its processes have global implications. The ROSETTA-Ice Project is a 3 year project, focused on the Ross Ice Shelf. In order to gather information on the Ross Ice Shelf, researchers employed a new system called IcePod to measure quantities such as thickness and height. When a magnometer was used, the signal was mostly uniform except for a spot about halfway across, where flux was detected. Suprisingly, this area of the boundary between East and West Antarctica was never noted before. Analyzing this new segment of data, the team discovered that the seafloor was much deeper on the East than the West, which affects ocean circulation. Essentially, this tectonic division prevents warm water from reaching the ice shelf’s grounding line for most of the year and slows melting. But there is a counteracting factor to account for the ice shelf’s melting pattern; the Ross Shelf Polynya, a zone of open water, contributes to rapid summertime melting along the shelf’s leading edge. From these observations, researchers conclude that all processes, including seemingly minor ones, must be accounted for in order to capture the essence of glacier dynamics.
Through melting, glaciers and their surrounding areas experience a decrease in albedo, a measure of the reflectivity of a substance. The melting of freshwater from glaciers triggers the rising of sea levels and also pushes down more dense saltwater, creating changes in deep-ocean currents that are part of the Thermohaline Circulation. Scientists hypothesize that these changes could eventually lead to the shutdown of this circulation altogether. If currents in the Atlantic Ocean are shut down, immense temperature shifts may occur. In fact, during the Last Glacial Period, 25 of these types of fluctuations occurred, known as Dansgaard-Oeschger events. And as we should all know, especially those of us enrolled in AP Environmental Science, climate change leads to destruction of ecosystems, elevation of sea levels, and increased frequency of natural phenomena such as floods and storms. The forecast is not looking too bright.
Despite a plethora of evidence that reveals the problems associated with glacial melting, some people are still failing to get the message. Many now understand the prevalence of global warming, but there have emerged trailblazers who say there is a silver lining that glacial melting opens up trade. The following quotation is from Senator Mike Pompeo: “Arctic sea lanes could become the 21st century’s Suez and Panama canals.” What a knee-slapper! Let’s try to focus on one positive aspect of climate change since there are too many negatives. This man also had the audacity to defend President Trump’s decision to pull out of the Paris climate accord, literally a day after warnings that extinction was impending for millions of plant and animal species. Here’s a quotation from Mike regarding the agreement: “I’m sure it was a good party.”
From the above passages on glaciers and the Ross Ice Shelf, you know that our planet is not as cool as it seems. Hopefully the tides will turn, using the U.S. Green New Deal as a framework. This proposal calls for environmental justice, and also secures universal health care and jobs to amend the economic inequality present in our infrastructure. We have the power to change our planet into a better and cooler one!
Some fun facts on glaciers:
Glacial ice covers about 10% of land on Earth.
It is thought that glaciers were once present on Mars.
Glaciers are the largest reservoirs of freshwater.
Alaska has more than 100,000 glaciers!
The world’s largest glacier is the Lambert Glacier in Antarctica with a width of approximately 100km and a length of 400km.
Red snow exists, and is created by a species of green algae.