Habitat destruction is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or die, thereby reducing biodiversity and species abundance. Wikipedia
Human activity, the consumption of fossil fuels, the acidification of the oceans, pollution, deforestation, and forced migrations threaten life forms of all kinds. It is estimated that one-third of corals, freshwater molluscs, sharks, and rays, one-fourth of all mammals, one-fifth of all reptiles, and one-sixth of all birds are heading towards extinction”.
Early spring temperatures in the town of Deadhorse, on the north coast of Alaska, average -17 degrees Celsius. But with global warming affecting the Arctic more than anywhere, things are changing fast. At the end of March 2019, temperatures in Deadhorse hit 3C, a whole 20C warmer than the long-term seasonal average.
When permafrost is frozen, plant material in the soil—called organic carbon—can’t decompose, or rot away. As permafrost thaws, microbes begin decomposing this material. This process releases greenhouse gases like carbon dioxide and methane to the atmosphere.
Sea ice is frozen water that forms, expands, and melts in the ocean. It is different from icebergs, glaciers, ice sheets, and ice shelves, which originate on land
While sea ice exists primarily in the polar regions, it influences the global climate. The bright surface of sea ice reflects a lot of sunlight out into the atmosphere and, importantly, back into space. Because this solar energy “bounces back” and is not absorbed into the ocean, temperatures nearer the poles remain cool relative to the equator.
When warming temperatures gradually melt sea ice over time, fewer bright surfaces are available to reflect sunlight back into the atmosphere. More solar energy is absorbed at the surface and ocean temperatures rise. This begins a cycle of warming and melting. Warmer water temperatures delay ice growth in the fall and winter, and the ice melts faster the following spring, exposing dark ocean waters for a longer period the following summer.
Changes in the amount of sea ice can disrupt normal ocean circulation, thereby leading to changes in global climate. Even a small increase in temperature can lead to greater warming over time, making the polar regions the most sensitive areas to climate change on Earth.