Sea ice extent is affected by winds and ocean currents as well as temperature. Sea ice in the partly-enclosed Arctic Ocean seems to be responding directly to warming, while changes in winds and in the ocean seem to be dominating the patterns of climate and sea ice change in the ocean around Antarctica.
Some differences in seasonal sea ice extent between the Arctic and Antarctic are due to basic geography and its influence on atmospheric and oceanic circulation. The Arctic is an ocean basin surrounded largely by mountainous continental land masses, and Antarctica is a continent surrounded by ocean. In the Arctic, sea ice extent is limited by the surrounding land masses. In the Southern Ocean winter, sea ice can expand freely into the surrounding ocean, with its southern boundary set by the coastline of Antarctica. Because Antarctic sea ice forms at latitudes further from the South Pole (and closer to the equator), less ice survives the summer. Sea ice extent in both poles changes seasonally; however, longer-term variability in summer and winter ice extent is different in each hemisphere, due in part to these basic geographical differences.
Sea ice in the Arctic has decreased dramatically since the late 1970s, particularly in summer and autumn. Since the satellite record began in 1978, the yearly minimum Arctic sea ice extent (which occurs in September) has decreased by about 40% [Figure 5]. Ice cover expands again each Arctic winter, but the ice is thinner than it used to be. Estimates of past sea ice extent suggest that this decline may be unprecedented in at least the past 1,450 years. Because sea ice is highly reflective, warming is amplified as the ice decreases and more sunshine is absorbed by the darker underlying ocean surface.
Sea ice in the Antarctic showed a slight increase in overall extent from 1979 to 2014, although some areas, such as that to the west of the Antarctic Peninsula experienced a decrease. Short-term trends in the Southern Ocean, such as those observed, can readily occur from natural variability of the atmosphere, ocean and sea ice system. Changes in surface wind patterns around the continent contributed to the Antarctic pattern of sea ice change; ocean factors such as the addition of cool fresh water from melting ice shelves may also have played a role. However, after 2014, Antarctic ice extent began to decline, reaching a record low (within the 40 years of satellite data) in 2017, and remaining low in the following two years.
Figure 5. The Arctic summer sea ice extent in 2012, (measured in September) was a record low, shown (in white) compared to the median summer sea ice extent for 1979 to 2000 (in orange outline). In 2013, Arctic summer sea ice extent rebounded somewhat, but was still the sixth smallest extent on record. Source: National Snow and Ice Data Center
Sea ice extent is affected by winds and ocean currents as well as temperature. Sea ice in the partly-enclosed Arctic Ocean
Arctic Ocean
The Arctic Ocean includes the North Pole region in the middle of the Northern Hemisphere and extends south to about 60°N. The Arctic Ocean is surrounded by Eurasia and North America, and the borders follow topographic features: the Bering Strait on the Pacific side and the Greenland Scotland Ridge on the Atlantic side.
seems to be responding directly to warming, while changes in winds and in the ocean seem to be dominating the patterns of climate and sea ice change in the ocean around Antarctica.
First, the Arctic is an ocean basin largely surrounded by land whereas the Antarctic is a continent surrounded by ocean, and these differing geographies affect sea ice. Second, while Arctic sea ice has declined directly in relation to warming climate, Antarctic sea ice has shown no clear trend.
Polar ice caps are melting as global warming causes climate change. We lose Arctic sea ice at a rate of almost 13% per decade, and over the past 30 years, the oldest and thickest ice in the Arctic has declined by a stunning 95%.
Answer and Explanation: The Arctic is melting faster than the Antarctic largely because the Arctic is not as cold. Because there is far less land in the Arctic than in the Antarctic the ocean has a much larger moderating influence on the land that is there.
Because a substantial amount of Antarctic sea ice forms at lower, warmer latitudes, less ice survives the summer. On average, about 40 percent of the Arctic Ocean's winter ice cover remains at the summer minimum, whereas in the Southern Ocean only about 15 percent does.
In the Arctic, an ocean is surrounded by continents, while Antarctica is continent surrounded by oceans. These differences in the arrangement of land and water contribute to differences in each polar region's climate, oceanic and atmospheric circulation patterns, and seasonal and long-term sea ice patterns.
One major difference between the Arctic and Antarctica is the location of the poles. The North Pole (90 degrees north) is located in the ocean covered by sea ice, whereas the South Pole lies on the continent of Antarctica.
The Arctic is an ocean basin surrounded largely by mountainous continental land masses, and Antarctica is a continent surrounded by ocean. In the Arctic, sea ice extent is limited by the surrounding land masses.
Over the past seven years, we've had three record lows.” This year, Antarctic sea ice reached its lowest annual extent on Feb.20 with a total of 768,000 square miles (1.99 million square kilometers). That's 30% below the 1981 to 2010 end-of-summer average.
Sea ice in the Arctic region has declined in recent decades in area and volume due to climate change. It has been melting more in summer than it refreezes in winter. Global warming, caused by greenhouse gas forcing is responsible for the decline in Arctic sea ice.
Summer Arctic sea ice extent is shrinking by 12.2% per decade due to warmer temperatures. Arctic sea ice reaches its minimum extent (the area in which satellite sensors show individual pixels to be at least 15% covered in ice) each September.
This is because there is land around the Arctic Ocean that can slow down winds as they travel around the Arctic. Because of this, warmer air from the south is able to mix with polar air sometimes. This is another reason why the Arctic is warmer. The Arctic may be warmer, but it's still cold.
Greenhouse gases (also known as GHGs) are gases in the earth's atmosphere that trap heat. During the day, the sun shines through the atmosphere, warming the earth's surface. At night the earth's surface cools, releasing heat back into the air.
Water warms and cools more slowly than land, so the ocean and areas near the ocean have fewer extremes of temperature. Even when it's covered by ice, the relatively warm temperature of the Arctic Ocean has a moderating effect on the climate, helping to keep the Arctic slightly warmer than Antarctica.
Scientists at the National Snow and Ice Data Center (NSIDC) and the National Center for Atmospheric Research (NCAR) found that satellite and other observations show the Arctic ice cover is retreating more rapidly than estimated by any of the eighteen computer models used by the Intergovernmental Panel on Climate Change ...
Antarctica is Earth's highest and driest continent. It's colder than the Arctic and has less surface melt. Warm, deep ocean water contacting the ice sheet base causes ice mass loss in several areas. Antarctic sea ice has shown record-high and record-low sea ice extents since 2013.
Antarctica is made entirely from ice whereas the Arctic is land covered in snow. If the Antarctic ice sheet melted, the world's oceans would rise by 60 – 65 meters. There are no trees or bushes that can survive living on the Antarctic. The only plants that can grow there are moss and algae.
The essence of Antarctica is glacial ice cover. The ice, which has accumulated over millions of years, is up to 3 miles deep and covers about 5.3 million square miles, or about 97.6 percent of the continent.
The main difference between the Arctic and Antarctica is that the Arctic is a frozen ocean, whereas Antarctica is an actual landmass, and a continent. The Arctic is at the North Pole, while the South Pole is found in Antarctica.
Introduction: My name is Corie Satterfield, I am a fancy, perfect, spotless, quaint, fantastic, funny, lucky person who loves writing and wants to share my knowledge and understanding with you.
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