| Popis: |
Este artigo analisa as mudancas ambientais que ocorreram no Artico ao longo das ultimas cinco decadas. O estudo foi realizado pela coleta de dados em artigos cientificos, livros e tambem relatorios de ONGs associadas a questao artica. Durante os ultimos 50 anos, o Artico mostrou a mais rapida aquecimento no Planeta, duas vezes mais que a media mundial, isso causou rapidas mudancas ambientais, como a reducao do volume das geleiras, o que contribui para o aumento do nivel medio dos mares; o degelo do permafrost, que libera grandes quantidades de dioxido de carbono (CO2) e metano (CH4) na atmosfera, intensificando o efeito estufa; a migracao da vegetacao em direcao ao Norte, alterando a disponibilidade de alimentos e os padroes de migracao dos animais; o aumento da temperatura da superficie do mar, o que pode causar a migracao de cardumes de peixes para areas mais ao Norte. A mudanca mais rapida, e a que mais chama a atencao, e a drastica reducao da area coberta por gelo marinho no verao. O Artico e o sinalizador do impacto das mudancas climaticas de origem antropica e caminha, rapidamente, para se tornar um ambiente diferente daquele conhecido desde as grandes descobertas. Em poucas decadas nao havera gelo marinho no verao, causando claras mudancas no ambiente fisico e com consequencias graves para a biota. Normal 0 false false false PT-BR JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:8.0pt; mso-para-margin-left:0in; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-ansi-language:PT-BR;} A B S T R A C T This article analyses the environmental changes that have occurred in the Arctic over the past five decades. The study was conducted by collecting data in scientific papers, books and also NGOs reports associate with the Arctic issue. During the past 50 years, the Arctic showed the fastest warming on the planet, more than twice the world average, it caused rapid environmental changes, such as reducing the volume of glaciers, which contributed to the increase in the mean sea level; the melting of permafrost, which releases large amounts of carbon dioxide (CO 2 ) and methane (CH 4 ) into the atmosphere, enhancing the greenhouse effect; migration of vegetation towards the north, changing the availability of food and animal migration patterns; increasing sea surface temperature, which can cause migration of fish shoals in areas further north. The fastest change, the one that draws the most attention, is the drastic reduction in the area covered by sea ice in the summer. The Arctic is a climate change beacon because of anthropogenic and walks quickly to become a different environment from the time known from of the great discoveries. In a few decades there will be no sea ice in the summer, causing clear changes in the physical environment and with serious consequences for the biota. Keywords: Arctic, Sea ice, Climate Change, Polar Geography. |
