Sagot :
Réponse:
description :
We’ve all seen the pictures of polar bears stranded on sea ice. They’re all too often used as the iconic poster animals of a rapidly changing climate. Yet every now and again, claims emerge in the media that polar bears’ plight might not be so serious after all.
Carbon Brief has dug through the literature and spoken to polar bear experts. While little is known about some remote polar bear populations, it’s clear there’s no scientific basis for such optimism. As temperatures keep rising, polar bears face a bleak future ahead, say scientists.
Analysis :
How are polar bear affected by climate change?
The Arctic is warming about twice as fast as the global average, causing the ice that polar bears depend on to melt away. Loss of sea ice also threatens the bear's main prey, seals, which need the ice to raise their young
Why is melting ice bad for polar bears?
Because of melting sea ice, it is likely that more polar bears will soon starve, warns a new study that discovered the large carnivores need to eat 60 percent more than anyone had realized. ... That's why the melting of the Arctic sea ice threatens polar bear survival.
How does the melting of the polar ice caps affect the environment?
While sea ice exists primarily in the polar regions, it influences the global climate. ... 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.
What are two effects of melting polar ice?
Melting Ice and Global Consequences
Melting Ice and Global ConsequencesThe most pressing of these involve: thawing permafrost and the potential for enhanced natural emissions of carbon dioxide and methane to the atmosphere; shrinking of mountain glaciers and large ice sheets with consequent sea-level rise and impacts on water resources; and.
How many polar bears are killed each year?
According to Liodden, between 1963 and 2016, an average of 991 bears were hunted worldwide every year, totaling about 53,500 bears. He calls that number “crazy high,” given how many polar bears are believed to be left and how slow they are to reproduce.
Cause :
What is causing the ice to melt?
Water that is under the ice and that has a temperature above the freezing point causes the bottom surface of the ice to melt. Warm surface waters cause the edges of the ice to melt, particularly in leads and polynyas.
concequences:
Climate change and polar bears. Temperatures in the Arctic are rising at least twice as fast as the global average and sea ice cover is diminishing by nearly four per cent per decade. The loss of sea ice affects polar bears' ability to find food, studies show.
protect : (N.B);
You can play a critical role in the fight to protect polar bears and other wildlife and their habitats from threats like climate change.
