Climate Change Raises Indigenous Species Quandary For Environmentalist

From "When to welcome ‘invading’ species: Climate refugees challenge environmental distinctions between friend vs foe" by Janet Raloff on ScienceNews:

As climate changes, some environments are becoming hostile to the flora and fauna that long nurtured them. Species that can migrate have begun to move into regions where temperatures and humidity are more hospitable. And that can prove a conundrum for officials charged with halting the invasion of non-native species, says Jon Jarvis, a biologist who for the past year has headed the National Park Service.

One problem: What’s native? Species move at will as conditions change. What’s native in one century may be gone five generations later. Newly arrived species, meanwhile, may be environmental refugees.

“Policies that are currently in place view those [immigrants] as exotics,” Jarvis says — invading homesteaders that should, at all costs, be evicted. But such species may be on the move simply “because this is their last refuge,” he points out.

Read the complete ScienceNews article here.

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Solution To Fixing The Ozone Layer Increased Global Warming

From "Beyond Carbon: How Fixing the Ozone Layer Contributes to Climate Change" by Adam Fischer on state of the planet blog:

Early on, HFCs [hydrofluorocarbons] became the primary CFC [chlorofluorocarbons] alternative. The man-made chemicals were ozone-friendly substitutes that could be used in consumer, commercial and industrial products (such as refrigeration, air conditioning, insulating foams, aerosols and fire extinguishers). HFCs, however, have one major shortcoming: their high global warming potential (GWP). A substance’s GWP is defined as the degree to which it contributes to global warming, relative to an equivalent amount of carbon dioxide (CO2). Since CO2 is the dominant greenhouse gas by volume, other gases are converted into CO2-equivalents according to their GWP; a substance with GWP of 10, for example, contributes to global warming 10 times as much as the same amount of CO2.

The dozen or so substances in the HFC family have GWPs ranging from 140 to 11,700. The lifespan of these chemicals also varies: the less harmful compounds stay in the atmosphere for just over one year, while the most damaging ones can last up to 260 years.
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Due to population growth, HFC emissions in developing countries could be as much as 800 percent greater than in developed countries by 2050. At that time, HFC emissions, when measured by their CO2-equivalent, would account for roughly 9 to 19 percent of carbon dioxide emissions (in business-as-usual scenarios). As a result of this higher-than-expected atmospheric concentration, the impact of HFC emissions on the climate is slated to be about three times greater than what the Intergovernmental Panel on Climate Change (IPCC) had anticipated.

Read the complete post here.

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