気候変動関係 今日の内外注目記事 19年12月22-28日


Planting trees alone will not stop global warming,FT.com,19.12.28


The science underpinning the idea is well understood: as trees grow they work as carbon sinks, absorbing the greenhouse gas from the atmosphere and storing it within their bodies. One study estimated that planting a trillion trees across the world would be enough to remove two-thirds of carbon emissions in the atmosphere thanks to human action. This could be done, the scientists argue, without infringing on the land used for agriculture and animal husbandry.

Unfortunately, the reality is more complex. Like all models, the efficacy of forests as a carbon sink depends on the assumptions made: agricultural land stores carbon too, albeit less than woodland. All estimates come with uncertainty. Planting trees changes the colour of the earth’s surface. Darker objects absorb more heat and tree cover in the northern hemisphere — particularly on tundra — can actually warm the ground closest to the earth, offsetting the beneficial effects.

Some “volatile organic compounds” produced by trees as pesticides or to attract pollinators can be greenhouse gases themselves, others react with compounds in the atmosphere to produce even worse emissions. Interaction with car fumes can produce ozone, which, at ground level, keeps heat trapped on earth. These chemicals are a particular problem in North America: clouds of VOCs produced by the forests in the Great Smoky Mountains, in Tennessee, give the national park its name.

Other problems come from maintenance: roughly half the trees planted to line the route of Britain’s planned High Speed 2 rail route died during a hot summer when they were not watered. Nor do trees always command public support. In Ireland, where the government is relying on new forests to offset agriculture, locals have objected to the choice of tree: fast growing non-native Sitka spruce that, they say, creates ugly monocultures.

Trees undoubtedly play a role in fighting climate change, but they have to be deployed smartly. That means shifting the debate away from numbers and towards getting the policies right. In truth, the only possible way of stopping the planet warming is to burn fewer fossil fuels. If measures to offset emissions from airlines and oil companies encourage us to keep using their services then the surge of tree planting will have failed completely.



石炭火力、消えた輸出制限 小泉氏案に縦割り行政の壁 日本経済新聞 19.12.27








On land, Australia’s rising heat is ‘apocalyptic.’ In the ocean, it’s worse.,The Washington Post,19.12.27

Tasmanian Aboriginals faced genocide, and now extreme climate change is threatening whats left of their culture.

Strands of bull kelp at Shelly Point in Tasmania. The Tasman Sea is warming, and once plentiful giant kelp forests have rapidly declined. Indigenous artists rely on a kelp habitat for traditional jewelry and basket making.

Oystermen work in Clifton Beach, Tasmania. Scientists are working with oyster farmers to reduce the impact of disease linked to warming waters.------

石炭産業の縮小求める声を「無謀」と一蹴 オーストラリア首相 AFPBB 19.12.23


NSW fires LIVE updates: PM rejects calls for more climate action,Sydney Morning Hereld,19.12.22



Fire and flood focus minds of bosses and investors,FT.com,19.12.23

For Southern California Edison, a US power company with 15m customers, the risks of climate change are already in its backyard.Edison’s electrical wires sparked two deadly wildfires in 2017 and 2018, and the company recently set aside a $4.7bn reserve fund for possible liabilities related to the fires.

Now it has embarked on a costly programme to upgrade its electrical lines and make its grid less likely to spark fires. “We are seeing the early manifestations of climate change in our state,” said chief executive Pedro Pizarro. “Beginning in 2017 and with the fires in northern California, those were at a scale that no one had ever imagined.”

He outlines what Edison is doing in response. The company is replacing 6,000 miles of bare electrical wire to reduce fire risk, installing thousands of micro weather stations that monitor wind speeds, and swapping out the oil in its transformers with a less flammable alternative.

For Edison International, the listed company that owns Southern California Edison, the financial impact of the fires has been serious. The company reached a $360m settlement agreement with the public entities that were damaged by the Thomas and Woolsey fires, and multiple other legal cases will determine damages to other parties.

For another California utility, PG&E, the impact has been even worse. PG&E started bankruptcy proceedings in January 2019 after a series of catastrophic wildfires left it on the hook for as much as $30bn in possible liabilities. Owing to the severe risk, PG&E had to shut off power to nearly 3m customers this autumn, to prevent its electrical wires from sparking another fire. Edison also used blackouts in areas of high risk, leaving about 200,000 customers without power.

The California wildfires and their impact on power companies are one of the most visible examples of how climate-related risks are starting to affect businesses, sometimes at a speed and scale that is unexpected. Over the past year, a growing number of companies and investors have been focusing on the physical risks of climate change, which include not just wildfires but also changing weather patterns, storms, and increased flood risks. Paul Polman, the former chief executive of Unilever said there had been a big shift in the way companies viewed climate-related risks.------









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