Arctic Circle Detailed Data (Geographical Terms)

The Arctic Circle refers to the dividing line between the northern frigid zone and the northern temperate zone, and the latitude is 66 34' north

Arctic Circle Detailed Data (Geographical Terms)

The Arctic Circle refers to the dividing line between the northern frigid zone and the northern temperate zone, and the latitude is 66 34' north latitude, which is complementary to the intersection angle of Huangchi, and most of it is the Arctic Ocean. The Arctic Circle includes Greenland, Northern Europe and northern Russia, as well as northern Canada. There are many islands in the Arctic Circle, the largest of which is Greenland. Due to the severe cold, there are relatively few species in the Arctic Ocean, mainly lichens and mosses, and few trees. Famous animals are polar bears, seals and whales.

Chinese name: Arctic mbth: Arctic latitude: 66 34 ′ North latitude Plants: lichens and mosses Main areas: Greenland, Northern Europe, northern Russia and other regions Animals: polar bears, seals, whales, etc. Climate: winter is cold and long, summer is short and cool, including country introduction: Russia, Canada, Greenland and other regions, history, resources, characteristics, climatic conditions, vegetation, vegetation distribution, and so on. The Arctic Circle, a latitude circle of 66 34' north latitude, is the southernmost boundary of extreme day and night phenomena in the northern hemisphere. In the area north of the Arctic Circle, the sun is oblique, the sun's altitude angle is very small at noon, and it is a long night (extreme night) for a while, so the solar heat obtained is very small, belonging to the northern cold zone. The Arctic Circle is the dividing line between the northern temperate zone and the northern frigid zone. Arctic Circle refers to an imaginary circle with latitude value of 66 34' north latitude, which is the dividing line between the northern cold zone and the northern temperate zone, and is complementary to the yellow-red intersection angle (latitude value of the Tropic of Cancer). The area north of the Arctic Circle is called "within the Arctic Circle". Usually, the area within the Arctic Circle is called the Arctic Region, which consists of the Arctic Ocean and its surrounding land, and its land part includes Greenland, Nordic countries, northern Russia, northern Alaska of the United States and northern Canada. There are many islands in the Arctic Circle, the largest of which is Greenland. Due to the severe cold, there are few species of life in the Arctic Circle. Plants are mainly lichens and mosses, and animals are polar bears, seals and whales. The Arctic Circle is also the boundary where extreme day and night phenomena begin to appear. In the area north of the Arctic Circle, there will be extreme days in summer and extreme nights in winter. Most historians in history believe that civilized human beings turned their eyes to the North Pole, starting from ancient Greece at the earliest. Because it is said that the Arctic Circle was first determined by the ancient Greeks. They found that the stars in the sky can be divided into two groups. One group is in the north of the world and can be seen all year round. The other group is near the zenith and the south, and they only appear periodically with the seasons. The dividing line between the two groups of stars is the circle drawn by Ursa Major, which happens to be the latitude circle of 66 33' north latitude, that is, the Arctic Circle. In fact, Pythagoras (582-500 BC) and his school despised the idea that the earth was square or rectangular. Their philosophical thinking makes them firmly believe that the earth is perfect only if it is spherical and can meet the needs of "cosmic harmony" and "number". Plato's student Aristotle (384 ~ 322 BC) laid the foundation of the concept of "earth". He even considered that there should be a continent in the southern hemisphere in order to balance the vast land in the northern hemisphere. Moreover, in order to avoid the embarrassing situation that the earth is "top-heavy" and its big head (North Pole) is facing down, the area around the North Pole should be a relatively light ocean. So, more than 2000 years ago, a Greek named Bizeas bravely set sail and began the first impact of civilized human beings on the Arctic. It took him about six years to complete the voyage, and he reached Iceland or central Norway as far north as possible, possibly entering the Arctic Circle. In 325 BC, Bezias returned to Marseille (now Marseille). After Bizeus 1200, in 870 AD, an ancient Scandinavian nobleman named Otta bypassed the northernmost cape of Scandinavia for the first time, bypassed kola peninsula and entered the White Sea. At about the same time as Ota, a Norwegian named Loki was sent to the northwest to find a new continent and discovered Iceland. The discoverer of Greenland was a Norwegian pirate named Eric the Red Face. He was deported after two consecutive murders in Iceland, which is already under the jurisdiction of Norway. Desperate, he had to pack his family and everything into a small boat without a canopy, and with a glimmer of hope, he crustily skin of head and rowed westward. After a rather difficult voyage, he finally saw a piece of land. The climate is at the best stage of the global mild period (which Europeans call the "medieval warm period"), making high-latitude areas like Greenland a suitable environment for life. Eric the Red Face lived there for three years and thought it was a good land, so he decided to go back to Iceland to recruit immigrants. In order to make this place sound more attractive, he gave a nice name, Greenland, a green land. Summer in the southern coastal area of Greenland is probably really a lush green. Sure enough, groups of immigrants came across the sea with their property and livestock. Since then, Greenland has flourished. At the peak, there were more than 280 residential areas with thousands of people, 17 churches. Not only did he establish trade relations with Europe, but the Pope even sent someone to collect parish taxes. However, 500 years later, around 1500, with the world climate fluctuating again (entering the Little Ice Age), the weather there became cold, so this once prosperous paradise gradually entered a state of silence. This period of human activities in the Arctic can be called spontaneous regional discovery period. Affected by multi-stage and long-term structural changes, sedimentation and magmatic activities, various metal deposits (spots) are all over the Arctic Circle and its adjacent areas, including Kiruna Iron Mine in Sweden, Norilsk Nickel-Copper-Platinum Group Element Deposit in Russia, Tomtul Niobium Polymetallic Deposit in Finland, Komi Chromium Deposit in Finland, Isu Chromium Mine in Greenland and Fisk Neset Chromium Mine in Canada and Voith Bay Nickel-Copper-Cobalt Mine in the United States. Statistics show that in the past 10 years, the output of platinum group elements in the Arctic region accounted for more than 50% of the world total, with gem-grade and industrial-grade diamonds accounting for 26% and 28% respectively, nickel, cobalt and chromium accounting for 22%, 2 1% and 15% respectively, and copper, iron and lead and zinc. In addition, according to statistics, the output of Arctic diamonds, platinum group elements and nickel in Russia accounts for 99%, 98% and 80% of the national total output respectively, and the output of chromium, manganese and gold accounts for 90%, 90% and 40% respectively. With the gradual warming of climate, the expansion of land area and the strengthening of prospecting and exploration, the discovery and development of a large number of metal deposits will greatly increase the annual output of mineral products in this area, thus injecting new vitality into promoting global economic and social development. Therefore, prospecting, exploration, development and utilization have always been of great concern and expectation to the international community. According to the report issued by the US Geological Survey, the available oil reserves in the Arctic Circle are estimated to be 90 billion barrels, which can meet the global oil demand for nearly three years. The Financial Times reported that the report is likely to intensify the sovereignty struggle among countries in the Arctic region, and Russia, the United States, Denmark, Norway and Canada all claim control over the Arctic region. The Geological Survey said in its first public report on Arctic Circle resources that the Arctic Circle has about 13% of the world's undiscovered oil reserves and 30% of the world's undiscovered natural gas reserves. Among them, the natural gas reserves in this area are 47 trillion cubic meters. According to the US Geological Survey, the vast Arctic continental shelf may constitute the largest unexplored remaining oil area on earth. In 2007, Russia planted a national flag on the seabed 4000 meters below the North Pole, which immediately attracted the attention of countries vying for mineral resources in the Arctic, especially oil and natural gas resources. In May, Denmark hosted a five-nation summit in the Arctic Circle in Ilulissat, Greenland, in an attempt to curb competition and reiterated that all countries should implement the United Nations Convention on the Law of the Sea to manage their territorial waters. At the same time, countries' interest in commercial development in the Arctic is gradually increasing. Royal Dutch Shell and Anglo-Dutch Energy Group both expressed their wish to participate in the energy development of Yamal Peninsula in Russia. In the United States, many companies are committed to the long-term development of the Arctic region in Alaska; There are also some large companies in Denmark that have expressed interest in participating in oil and gas exploration along the coast of Greenland. According to the current United Nations Convention on the Law of the Sea, because there is no evidence that the continental shelf of any country extends to the North Pole, the North Pole and its vicinity do not belong to any country, and the Arctic Ocean covered with ice around the North Pole is regarded as an international sea area. However, the further exploration of mineral resources reserves in the Arctic Circle has also been worried by some environmentalists. The largest port city in the Arctic Circle: Port Narvik is the largest port city in the Arctic Circle of Norway and an important seaport in northern Sweden and Finland. On the southeast bank of Uft Fjord along the coast of the Norwegian Sea, there are more than 10,000 people in this port city. The northernmost botanical garden in the world: Kara Peninsula of the Soviet Union, located in the Arctic, is in danger of snowstorm or frost even in normal summer. However, the flowers and fruits there are still flourishing. Not far from Kirovsk, there is an "Arctic-Alpine Botanical Garden", which is one of the largest botanical gardens in the former Soviet Union and the northernmost botanical garden in the world. The unique landscape of the Arctic Circle Snow Tree Airport in the Arctic Circle: in Kangerlussuaq, Greenland, 66 degrees 33 minutes north latitude. Countries in the Arctic Circle: There are Arctic Ocean, islands and land in the Arctic Circle, belonging to Russia, the United States, Canada, Denmark, Iceland, Norway, Sweden and Finland. The coldest place in the Arctic: The average temperature in the Arctic in winter is -20 degrees Celsius, and in many places it is -33 degrees Celsius. The coldest place is near Omiya Ren Zhen in the northeast of Siberia, 2898 kilometers away from the pole, reaching MINUS 53 degrees Celsius. The northernmost city in the world: Longyear, the capital of Svalbard, Norway. Longyear was originally an American name. Longyear came to Svalbard in 1904 and bought the coal mine on the island from the Norwegian. Two years later, Americans built their first house near the coal mine, and the coal mine manager named the place "Longyearbyen" after their boss. This place, which used to have only one house, has now developed into a town of 1200 people. There are post offices, schools, banks, hospitals, newspapers, restaurants, shopping malls, museums and so on. It is located deep in the Arctic Circle, hidden at 78 degrees north latitude. At this latitude of the earth, there is almost no land. This is a cold place, and the sun can't be seen for four months every year. The earth is covered with ice and snow, and there is darkness all the time. In the other four months, the sun hardly sets. Climatic conditions Due to the short sunshine time in the Arctic Circle, the height of the sun is not high (the thickness of the atmosphere through which the sunlight passes increases, resulting in the increase of the reflected and lost heat), and the reflection of the solar light by the surface ice sheet, it is cold all year round, belonging to the cool climate of Leng Xia in winter. After entering the Arctic Circle, cold air cools and settles, forming a polar high pressure area in the polar circle. The arctic circle flows from the polar high-pressure area to the air at low latitudes. Due to the deviation of the earth's rotation, it all flows eastward, forming a northeast wind (blowing from northeast to southwest) in the arctic circle, which is called polar easterly wind. Near the Arctic Circle, the cold air carried by the polar easterly winds sinks, resulting in a near-surface northeast wind, while the warm air from the north meets the polar cold air from the north, forming a front, which is called a polar front. Because the warm air is lighter, it climbs above the heavier southerly cold airflow, forming a sub-polar updraft. The updraft is divided into two branches: southbound and northbound. The southern branch sinks again at about 30 north latitude, forming a mid-latitude circulation circle in the northern hemisphere. The northward branch settled near the North Pole and completed the high latitude circulation circle. Due to the influence of subtropical updraft, the air pressure near the Arctic Circle is low, which is called subtropical low pressure area. In Eurasia, the Mongolian-Siberian high has a strong influence in winter, which makes Eurasia and northern North America have a continental climate of sub-frigid zone, and the sub-polar low can only be kept in the ocean. The isotherm of vegetation distribution in the Arctic Circle 10℃ is roughly the same as that in the northern hemisphere in July, while the latter basically coincides with the tree line of the Arctic, so all three can be used as the criteria for defining the Arctic region. Near the Arctic Circle is the transition zone between the sub-frigid coniferous forest belt and the Arctic tundra. Trees have been difficult to grow because of frozen soil and howling cold wind. From south to north, the continuous forest began to disappear, replaced by sparse mixed vegetation of trees and shrubs, and finally only moss and lichen were left, which became a tundra landform. Vegetation Growth 20 13 April 10, researchers from the American Museum of Natural History, Cornell University and other institutions reported in the journal Natural Climate Change that they had established a set of models to predict the vegetation changes in the Arctic Circle in the coming decades according to the global future temperature growth trend. It is predicted that in the next few decades, nearly half of the species of surface vegetation in the Arctic Circle will change, and the range of green vegetation and forest coverage will increase significantly. For example, researchers say that in some parts of Siberia, the tree line will extend hundreds of miles north. Researchers say that vegetation changes will continue to affect the Arctic ecological environment. The snow and ice covered in the Arctic Circle can reflect most of the sunlight, while the green vegetation can absorb a lot of sunlight. Increasing green vegetation may cause the temperature in the Arctic to rise further. Special phenomenon Extreme day and night (also called eternal day and night) is a unique phenomenon in the polar regions of the earth, which means that it is day (extreme day) or night (extreme night) within 24 hours a day. The Arctic Circle is the only place in the northern hemisphere where extreme days and nights may occur. Every year on March 2 1 of Gregorian calendar, that is, at the vernal equinox, the sun shines directly at the equator. From this day on, extreme days began to appear in the Arctic Circle. At first, it was only in the northern area. By the solstice in summer, the sun appeared extremely bright directly on the Tropic of Cancer (the 23 rd polar circle of north latitude), and then gradually expanded to the North Pole and then to the whole Arctic Circle. June 22, 26'), at this time, the polar solar range in the northern hemisphere reached the largest, covering all places north of the Arctic Circle. After that, the range of extreme days gradually narrowed, until around the autumnal equinox on September 23, only the points on the Arctic Circle had extreme days. After this day, starting from midnight, it started at a point on the Arctic Circle and then spread to the whole Arctic Circle. During the winter solstice around February 22, 65438+, the sun was shining directly on the Tropic of Capricorn, and the whole area north of the Arctic Circle was extremely night. Then, the scope of the polar night gradually narrowed, and the polar night ended and resumed on March 2 1 of the following year, that is, at the vernal equinox. In the Arctic Circle, the higher the latitude, the longer the extreme day and night appear. Near the North Pole, nearly half of the year is extremely bright and the other half is extremely dark. Near the Arctic Circle, there are only a few days of extreme days and nights. In the Arctic Circle, the sun can never shine directly, and the height of the sun is not high, reaching its maximum height on the solstice in summer. Where the latitude is α, the maximum solar altitude angle is113 26'? α, less than 46 52'. On August 5, 2008, the temperature in the Arctic Circle exceeded 30℃.