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A couple of negatives aspects are the threat to polar bears and the loss of Inuit hunting traditions. Another downside is that marine mammals could find their breeding season disrupted as the Northern Sea Route would be being used extensively. Even more negatives for the Northern Sea Route begins with how the climate will be affected. Countries will fight over parts over the Arctic sea ice, marine mammals environments will be at stake due to no ice, and it will affect the way the animals live in their habitat.
Natives, who hunt in the ocean, will have to find secondary sources to eat, because some of the marine mammals could die out from no ice. Another reason is polar bears would be highly threatened because they use the ice to hunt the other animals for survival. It is highly likely that they will become more endangered, but they will not go extinct.
Seals would be a big factor in this because their breeding grounds are on ice, if the ice happens to go out they will have to find a new way to breed, sleep, and play with out the ice. It will be worrisome to allies who own part of the Arctic like Canada and the US. Without the sea it will bring more carbon dioxide into the atmosphere in the world.
The climate is changing, even though it is happening very slowly. Different elements affect climate change. Most scientists believe it is mostly due to human-related activities, like burning fossil fuels.
This is when snow and ice melts. After the snow and ice melts, what lies dark water and bare rock is revealed. The warmed surroundings melt the snow and ice that is around it, and this, in turn, reveals more water and rock. Climate change affects everything living in a region.
It even changes the make up of the entire ecosystem. It alters life cycles for plants and animals. Plants, animals and people will have to adapt to the changing climate. Also every plant and animal plays a role in their region, so if one species dies out or becomes extinct, due to the climate change, it will affect many others.
In conclusion, the Arctic sea ice is incredibly important for the survival of humanity as well as animals. Without the Arctic sea ice, the daily dynamic would change drastically for a lot of the Native Alaskans living in coastal areas.
A lot of Alaska Natives depend on the sea ice for subsistence hunting in order to feed their families. The entire ecosystem gets thrown out of balance when the sea ice begins to melt, and it will eventually affect humans outside of Alaska or the northern region of the globe. Even though the melting Arctic sea ice would open up new shipping lanes in that allowed goods to be carried through the Arctic at a much faster rate, is it truly worth the cost?
Should we not be doing everything we can as human beings to stop this climate shift and preserve the ice in the Arctic Regions? Truly, many lives depend on how robust the Arctic sea ice remains, and all those who rejoice at the thought of a faster shipping lane do not fully understand the implication of a melting Arctic.
You must be logged in to post a comment. Biochemistry Chemistry Environmental Sciences. Tom Tomaganuk. No Comments. Abstract: How does the reduction of Arctic Sea ice directly impact the habitat of human beings? Overview of the number of fish species in Canadian Arctic waters. Christiansen, If this keeps happening, there will be a huge abundance in fish. Works Cited Christiansen, J. Arctic Report Card.
Retrieved November 13, , from Marine Fishes of the Arctic: www. Retrieved November 26, , from www. The Carbon Brief. Arctic Life, On Thin Ice. Science , , Naam, R. Guest Blog. USA Today. Retrieved November 26, , from Arctic Climate Change: www. Post Views: 29, Previous Land- or Ocean-Based Conservation. Related Posts. Leave a Reply Cancel reply You must be logged in to post a comment. Articles of the Week. Jellyfish Apocalypse: Problems, Causes and Opportunities 3 years ago. Science in the News.
Our Sixth Mass Extinction. To extend the historical record of Southern Hemisphere sea ice back in time, scientists have been investigating two types of proxies. One reference is the records kept by Antarctic whalers since the s, which document the location of all whales caught. Because whales tend to congregate and feed near the sea ice edge, their locations could be a proxy for ice extent.
A second proxy is the detection of phytoplankton-derived organic compounds in Antarctic ice cores. Since phytoplankton grow most abundantly along the edges of the ice, the concentration of sulfur-containing compounds has been proposed as an indicator of how far the ice edge extended from the continent. Currently, only the satellite record is considered sufficiently reliable for studying Antarctic sea ice trends.
Valuable data are collected by satellite sensors that observe the microwaves emitted by the ice surface. Unlike visible light, the microwave energy radiated by ice passes through clouds. This means it can be measured year-round, even through the long polar night.
Reliable records of Arctic sea ice began in , and satellites have offered a near-continuous record since The plot above shows sea ice anomalies—how much Arctic sea ice cover was above or below the norm.
These observations are processed into digital picture elements, or pixels, with each representing a square of 25 kilometers by 25 kilometers.
Scientists estimate the amount of sea ice in each pixel. There are two ways to express Earth's total polar ice cover: ice area and ice extent. To estimate area, scientists calculate the percentage of sea ice in each pixel, multiply by the pixel area, and add up the amounts. The threshold—based approach may seem less accurate, but it has the advantage of being more consistent. By reducing the uncertainty in the amount of ice, scientists can be more certain that changes over time are real.
Beyond measuring ice coverage, satellites can also help scientists get a better handle on thickness. Data from this instrument are converted into maps of sea ice thickness—a useful tool for tracking change over time and for monitoring winter season ice growth.
Researchers also monitor sea ice using aircraft. The number of melt ponds that form early in the season can affect the minimum extent reached by sea ice in September. Operation IceBridge has monitored sea ice during late winter since Arctic sea ice occupies an ocean basin mostly enclosed by land.
Because there is no landmass at the North Pole, sea ice extends all the way to the pole, making the ice subject to the most extreme oscillations between wintertime darkness and summertime sunlight. Likewise, because the ocean basin is surrounded by land, ice has less freedom of movement to drift into lower latitudes and melt. The Bering Strait is one of the few outlets through which sea ice exits the Arctic Ocean. Arctic sea ice generally reaches its maximum extent each March and its minimum extent each September.
This ice has historically ranged from roughly million square kilometers about 5. In recent years, however, those numbers have been much lower.
On time scales of years to decades, the dominant cause of atmospheric variability around the North Pole is the Arctic Oscillation. The AO is an atmospheric seesaw in which air masses shift between the polar regions and the mid-latitudes. The shifting can intensify, weaken, or move the location of semi-permanent low and high-pressure systems. These changes influence the strength of the prevailing westerly winds and the track that storms tend to follow.
The minimum Arctic sea ice extent occurs in September. The maximum is in February or March. Arctic sea ice maxima and minima have been shrinking for three decades. The thin, young ice that forms in these leads is more likely to melt in the summer. The strong winds also tend to flush ice out of the Arctic through the Fram Strait.
Multiyear ice is less likely to be swept out of the Arctic basin into the warmer waters of the Atlantic. However, in recent years, the relationship between the Arctic Oscillation and summer sea ice extents has weakened. For example, a strong negative phase in the winters of and was not enough to maintain high levels of ice cover.
Clearly some other factors can override the relationship. In September , Arctic sea ice reached a minimum extent of 4. The ice then grew during the winter months and reached its annual maximum extent in March , measuring By September , sea ice dropped to 4. The record lowest minimum occurred in September when sea ice plummeted to 3.
That was well below the previous record of 4. Between and , the average monthly extent for September declined by In every geographic area, in every month, and every season, Arctic sea ice extent is lower today than it was during the s and s. Natural variability and global warming both appear to have played a role in this decline. After the mids, the AO was often neutral or negative, but sea ice failed to recover. Instead, a pattern of steep Arctic sea ice decline began in The AO likely triggered a phase of accelerated melt that continued into the next decade because of unusually warm Arctic air temperatures.
Many global climate models predict that the Arctic will be ice free for at least part of the year before the end of the 21st century. Some models predict an ice-free Arctic by mid-century. Depending on how much Arctic sea ice continues to melt, the ice could become extremely vulnerable to natural variability in cycles such as the Arctic Oscillation.
Arctic sea ice cover peaks each year in March, and reaches its minimum in September. In arctic ice reached the lowest extent ever recorded, well below the historical average blue dashed line. Declining sea ice will lead to a loss of habitat for seals and polar bears; it also should increase encounters between polar bears and humans.
Indigenous peoples in the Arctic have already described changes in the health and numbers of polar bears. As sea ice retreats from coastlines, wind-driven waves—combined with thawing permafrost—will likely lead to more rapid coastal erosion.
Other potential impacts include changed weather patterns. This is an area of active research, as scientists try to tease out the possible links between sea ice loss and mid-latitude weather patterns. The loss of sea ice exposes shorelines to the full force of wind and waves, resulting in rapid erosion. This cabin fell into the Beaufort Sea, a region where some coastlines retreated more than 24 meters 80 feet in Some researchers have hypothesized that melting sea ice could interfere with ocean circulation.
In the Arctic, ocean circulation is driven by the sinking of dense, salty water. Fresh meltwater coming primarily from the Greenland Ice Sheet could interfere with ocean circulation at high latitudes, slowing it down. Changes in the location and timing of sea ice growth—where the dense salty waters are formed and then sink to the bottom—may also be an important factor. The Antarctic is in some ways the opposite of the Arctic.
The Arctic is an ocean basin surrounded by land, with the sea ice corralled in the coldest, darkest part of the Northern Hemisphere. The Antarctic is a continent surrounded by ocean. Sea ice around Antarctica peaks in September and reaches a minimum in February.
Roughly 15 million square kilometers of ice melt and freeze during the annual cycle. Total Antarctic sea ice peaks in September—the end of Southern Hemisphere winter—historically rising to an extent of roughly million square kilometers about 6. Ice extent reaches its minimum in February, when it dips to roughly million square kilometers about 1. To study patterns and trends in Antarctic sea ice, scientists commonly divide the ice pack into five sectors: the Weddell Sea, the Indian Ocean, the western Pacific Ocean, the Ross Sea, and the Bellingshausen and Amundsen seas.
In some sectors, it is common for nearly all the sea ice to melt in the summer. Antarctic sea ice is distributed around the entire fringe of the continent—a much broader area than the Arctic—and it is exposed to a broader range of land, ocean, and atmospheric influences. For these reasons, it is more difficult to generalize the influence of climate patterns to the entire Southern Hemisphere ice pack.
In the Southern Ocean, sea ice fringes the entire Antarctic continent. Researchers typically subdivide Antarctic sea ice into five sectors, each influenced by different geography and weather conditions. Antarctica experiences atmospheric oscillations and recurring weather patterns that influence sea ice extent. Like the Arctic Oscillation, the Antarctic Oscillation involves a large-scale see-sawing of atmospheric mass between the pole and the mid-latitudes.
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