Title: Tundra - Effects of human activities and climate change | Britannica
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Effects of human activities and climate change
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Content: Hunting, oil drilling, and other activities have polluted the environment and have threatened wildlife in tundra ecosystems. Environmental scientists are concerned that the continued expansion of these activities—along with the release of air pollutants, some of which deplete the ozone layer, and greenhouse gases, which hasten climate change —has begun to affect the very integrity and sustainability of Arctic and alpine tundra ecosystems. For example, the increased occurrence of tundra fires would decrease the coverage of lichens, which could, in turn, potentially reduce caribou habitats and subsistence resources for other Arctic species. surface temperature
Projected surface temperature changes from the Fourth Assessment Report of the IPCC. Encyclopædia Britannica, Inc.
The effects of climate change on tundra regions have received extensive attention from scientists as well as policy makers and the public. This attention partly stems from the tundra’s high sensitivity to the general trend of global warming. While the average global surface-air temperature has risen by approximately 0.9 °C (about 1.5 °F) since 1900, average surface air temperatures in the Arctic have risen by 3.5 °C (5.3 °F) over the same period. Many parts of the region have experienced several consecutive years of record-breaking winter warmth since the late 20th century. In some locations, this record-breaking winter warmth has been unprecedented; three-month winter mean temperatures in Norway’s Svalbard archipelago in 2016 were 8–11 °C (14.4–19.8 °F) higher than the 1961–90 average.